CORRECTIONS, thanks to the folks who commented below: 0:08 - Unbonding is removing the ground strap that connects ground and neutral, not ground to frame. 3:25 - The generator is a single phase, so it couldn’t run “out of phase.” Instead of 120v going to each leg, most or all of the 240v was going to one leg, and almost none to the other.
I just removed the ground wire from the plug terminal that goes into my generator and left my generator bonded. That way I can still use it around my property remotely and have the bonded ground.
Each leg always has 120v to neutral. The 240v is across the two legs without a neutral. With a missing neutral, 240v is present across the loads of the two legs in series. Since the loads will not be equal, the voltage drop across devices on each leg is different and some devices will see too high of a voltage and may burn up as happened with your surge suppressors.
@bluesrider. The 240v cable between my generator and box plugs into the generator carrying the 2 hits, ground and neutral. When the wires from the female receptacle on the generator go down to where you unbounded your Westinghouse they connect to their respective tabs, which are then bonded. What’s the difference between removing that jumper bond wire on the generator and having your transfer switch only connect the neutral, 3 wire config, and me removing the copper ground wire in the cable from the male ground pin on the plug? I don’t have a transfer switch I’m wired into a 50 a breaker in the main panel and manually switch off the grid after the Power goes out.
(Unbonded) For 20 years I’d been connecting my bonded generator to my main panel with no problems. After seeing a James Condon video on this topic I unhooked the cable ground at the plug. Had a power outage and no problem, but I don’t want any problems. I just don’t see the difference between what I did with the cable and unbonding inside the genny. I have an 8’ ground rod right below the main box I plug the gen into.
@@jtjones4081 That was very foolish . Now you have no ground to the generator. If there is a ground fault the circuit breaker on the generator won't see it and it will burn until the wires burn through. Not to mention various code violations.
A 120/240 generator cannot go out of phase as it only has one phase. What probably happened is loosing the neutral caused the power being consumed to find an alternate route back to the generator. Meaning that instead of 120 -N - 120. you had for example 50-N-190. Those surge protectors operate by clipping any over voltages. depending on the specific component (a metal oxide Varistor is usually used and rated around 140-150v) will cause the Protector to try to protect. IN this case the Surge it was seeing wasnt due to power issues as a fault in the wiring of the cable. Glad you found what caused it.
Over revving will also clip them MOV's, Diodes, trans, IC and wipe out most battery chargers, computers, digital equipment etc. 130v at 65 hz starts driving shit crazy and turns the Genie into smoke
Your partially correct, You will read different voltages at the loads but keep in mind that the generator still only does 120vpk 240v p/p If you have equal loads say two identical fridges can you run them in series no neutral? Or say have 120v compressor in series with a deep freezer in the garage? Will one run and not the other? Ahhh the age old question? Yes or no, in or out, up or down, right left, 1/0, will one burn up and not the other? Keep in mind what is in series and what is in parallel, isn't electricity fun.
@@bluesriderDFhe's on the right track but his explanation is erroneous. The lost generator neutral caused a backfeed through all the branch circuit neutrals putting 240v on your 120v equipment.
@@ianbelletti6241 No. he is spot-on. It does not put 240V on your 120V legs, it depends on the impedances of the connected loads at any given time. It can vary between 0V and 240V on a leg (and the converse on the opposite leg). I did not see any errors or typos in what he stated.
Definitely a classic example of a floating neutral. A couple years back went on a service call in a late 1970s home, where the TV, DVR, DVD player and stereo system in living room smoked up so bad it set off the smoke detectors in the hallway and master bedroom after a 1500 watt electric fireplace had been running for over an hour, plugged into a different outlet on the other end of the living room. Come to find out, all the receptacles were backstab connection and part of a multiwire circuit (L1 & L2, sharing a common neutral) and the neutral burned up on a receptacle upstream, making everything downstream into a series 240V circuit and depending on the load balancing, voltages applied accross the load can range from nearly 0, to nearly 240. Also pointed out to the homeowner and corrected, the two single pole breakers controlling the multiwire branch circuit, by installing an identified handle tie to ensure that if either leg trips the entire circuit is dead, protecting anyone working on it thinking its dead when in fact one leg is still hot, evidently this wasn't required when the home was built. This whole catastrophe could have been avoided, had article 300.13 (B) of the NEC been applied which states that for multwire branch circuits, the continuity of the grounded (neutral) conductor shall not depend on connections to receptacles, lamp holders and so forth, where the removal of such devices would interrupt continuity. What this means, is that the neutral on those receptacles should have been connected via a pigtail
This was one of my arguments for not unbonding my generator, having more or less a redundant neutral. In the end I did unbond it and have not had any issues, but this video shows the importance of having a good solid connection all the way around.
Why did you unbind it if you were for bonding? This topic is so confusing, nobody has a definitive answer. I haven't had an issue running my generator bonded.
@@bluesriderDF That's rough. A continuity test is usually enough. My first thought after all the troubleshooting was "why didn't you test the cable first since it's the easiest? "And then I realized I would have followed the same process as..."it's just a cable and how could THAT be the issue?"
The following is an experience I had a friend asked me to look at. What I found out I had never heard of. When turning on several lights in the house, the house lighting would slow flicker or surge up and down, get brighter then dim. Everything checked out to be normal throughout the house, so I assumed it was a lost neutral somewhere in the house. I have years of experience in residential, commercial, and industrial electrical field's but I'm not a licensed or insured electrician and screwing with a lost neutral can burn down your house, so I recommended having a licensed and insured electrician take a look. They did. The electrician found everything was normal throughout the house also. Eventually he found the problem. It was a mixture of different brands of LED light bulbs throughout the house causing the fluctuation. My friend changed all the LED light bulbs to one brand and that fixed the problem.
I swear I said to myself about 10 seconds after you suggested an immediate fire, "His cord has a faulty neutral, and the ground wire previously provided neutral because they were bonded at the generator." I'm glad you and your house are still standing to talk about it.
there are a lot of lessons in this video. This could be a whole lesson for an apprentice or journeyman refresher course. Open neutrals are something we run into a lot and are often times at the service point. Interesting video and I am glad that you are safe!
The surge protector did catch on fire because it had a very /low/ resistance. Not high resistance. The MOVs inside go low resistance when exposed to over voltage, and they are supposed to short out and blow your fuses. It can be dangerous supplying power from a generator as it might no be able to make enough short-circuit current to trip thr fuses.
That unfortunately isn't as true as you would normally hope. With the increased use of better protective earth connects you can easily get a competition between the supply company's attempts at providing a low impedance neutral (truly reference to earth at the generators, subs, and transformers) and the parallel earthing impedances for the multipoint safety protections. It gets worse in three phase supplied zones where the individual phase takes are unbalanced and the protective earth-neutral bonding enhances the diverted neutral current. It will depend on your generic location as to whether the local buildings and construction styles will make it more or less likely , and not forgetting 'fault' conditions.
Thank you, thank you, thank you. I have been stressing about the floating neutral question for about a month now and I am almost finished with the complete installation of my system. You answered my questions and really gave me down to earth answers. I'm good now. Thanks man.
Interesting. Thanks for sharing. Lost neutrals and meltdowns are not something I normally associate with generator usage. I made up my own generator extension cords. After watching, I'll open them up to absolutely sure connections are still snug after 2 years...especially the neutral.
Side note: 250.30 of the NEC requires separate bonding wire to the service panel when connecting a generator in this situation if the neutral remains connected to the grid. However, if the transfer switch also separates the neutral from the grid, then the generator needs to be internally bonded.
I am not an electrician, but have been doing home renovations for 30 years. I installed a 120 volt Coleman RV heat pump in my kitchen ceiling. I also installed a dedicated duplex outlet for this purpose. However, when I turned on the heat pump the first time, it ran but was noisy. So I shut it off and went to inspect the heat pump itself. The motor case was extremely hot. I troubleshooted the possibilities, and found I had connected the neutral to the neighboring breaker, so the circuit was 240 volt. OOOPS.. Five years later, by some magic, the heat pump is still working. Oversight happens to everyone, so your extension cord failure is not a surprise, but glad you figured it out. (PS: during the course of home renovations, I found many many electrical and plumbing faults, done by the "PROFESSIONALS".)
Before you unbonded your ground at the generator, your neutral current was flowing through the ground conductor in the extension cord and the bonding jumper. So it was a related problem and unbondining your generator is correct. A ground rod would NOT have mitigated this problem even if you had connected it directly to your service entrance rod. That would have made the neutral current flow through your ground rod wires.
When the neutral get loose like that one leg goes high, the other one goes almost to zero volts like you said on the video and everything is connected in series between the two phases. The culprit is the loose neutral connection. It can also happen on the utility side of the installation.
Thanks for sharing on your experience with this!!!! I'm an electrician, have installed many different types of home generator connections and transfer switches, panels , etc. But that Generator "Cord Set" some call it could be a failure that me as an electrician may not catch in my Testing, after an installation. If the home owner replaces a cord, and gets a bad/defective cord set, the result could be very bad. So important to validate/inspect/test the cord set as well. God bless
I suspect this is what happened to me. A few years ago we needed the generator, I plugged it in just like I always do and the Keurig coffee maker took a hit. Seems like we lost other electrical appliances also. Inspection of the extension cord showed a loose wire. I don't remember which one it was. But I suspect it was the neutral. I tightened all wires in both ends of the cord and everything began to work correctly. Thanks for posting this, it helps me understand what I experienced.
Thanks for taking the time to make and post this video. I had this happen to a friend of mine as well. It blew out a GFCI wall socket in the master bath, and in the master bedroom, a TV and a clock radio. Oddly, everything was isolated to his bedroom and master bath, though the open neutral was on the generator-to-transfer switch cord.
The same exact condition that you experienced occurs all too often when utility feeds coming into a building looses the neutral connection, usually at the pole due to windy conditions or sometimes in the meter pan due to corrosion. The voltages go out of balance and cause all kinds of grief. The first clue is when some lights are dimming while others are too bright and subsequently burn out. There isn’t much that can go wrong that is worse than this.
If you haven’t already done so, I’d recommend a whole house surge protector. Although if it’s installed at the main panel and you are running over the transfer switch circuits only that would probably be bypassed. One thing I’ve done at my house is install a voltmeter at where the generator goes into the transfer switch. That way I could see abnormal high voltage if my neutral was loose.
I use a generator interlock on our service entrance. Like you I added a generator status panel next to it that shows current and voltage on each leg, and frequency. The generator is electric start so the status panel includes a DC voltmeter to monitor battery voltage and verify the battery maintainer is working properly. I also recommend installing a whole house surge protector in addition to point of use ones and also at hard wired devices.
So basically the lesson here is that it takes maybe 15 seconds with a meter to check the continuity of your cord. And probably 99% of us have never done that. We all just assumed that if we didn't make it up ourselves, that it came from the factory correctly wired. That is a dangerous assumption, more dangerous than most of us realized. Thanks buddy, I am going to go get my meter out right now.
Thank you very much, we need more people to learn how to figure things out. Everybody in they're life will need to have this type of reasoning in order to survive, can't just leave it up to somebody else all the time Thanks again for teaching people.
I'm an electrician retired after over 40 years in the craft. The reason that the voltage went too high on those Surge Protectors is that without an intact neutral the voltage will fluctuate with the amount of loading on each of the generator's energized conductors. The most heavily loaded side will have the reduced voltage and the lightly loaded energized conductor will have the higher voltage. The greater the difference in the loading the greater the difference in the voltage. In your case the load must have been markedly different on the 2 energized conductors and that produced a destructively higher voltage across the lighter loads which must have included those surge protectors. Why that happened is that in most cord sets of under size 2 American Wire Gauge (AWG) all of the conductors are the same size including the Equipment Grounding Conductor (EGC). Since the Neutral Conductor of the cord had an open connection at one end it was not carrying any current. The EGC (Grounding Conductor) of the cord had been carrying the imbalance current from the Grounded (neutral) busbar of the panel to the frame of the generator. The Main Bonding Jumper of the generator windings had been carrying the unbalanced current of the different loads the rest of the way from the generators frame back to the center point of the generator's windings. Under those circumstances both energized conductors carried their portion of the load current while the Equipment Grounding Conductor (EGC) carried the difference between the current flows on each of the energized conductors. Theoretically that is the wrong pathway for that current to return to the center point of the generator's windings but nobody consulted the electrons about our theory and they don't give a tinker's dam about what we think that they should be doing. Electric current does not take the path of least [resistance + reactance =] impedance. Impedance is the sum of the resistance and reactance to the flow of AC current. AC electric current takes all of the pathways available in inverse proportion to their respective impedances. Once you unbonded the generator winding's electrical mid point from the frame of the generator the difference in the current flowing on the 2 energized conductors had no way back to the source. That shifts the electrical midpoint of the generators voltage away from the heavier loaded portion of the generator's windings and toward the lighter loaded end of the generator's windings. There are devices that are usually used to protect recreational vehicles (RVs) from failures of the RV park's electrical system. One of the things that they do is disconnect the cord from the power source if the neutral conductor develops a high impedance or goes open. Using one of those plugged into the 120/240 volt plug of the Generator will disconnect the cord from the generator if either of those conditions were to develop. Tom Horne
I have a question for you Tom. Would you advise against removing the bonding jumper of the generator when tied in to a residential panel that’s bonded itself ?
@joshe9518 If your panel is bonded, that's why you should remove it from the generator, so you don't have more than one N-G bond in your system, per NEC code.
They are harder to find but I use metal surge suppressor strips instead of plastic. They contain overloads and don’t melt. I was convinced one year when as an IT professional I came into work and found over a dozen of those plastic strips burnt or damaged from a surge. Worth the extra cost and safety.
Thank you for posting this video, in all honesty I have never even given the cord a second thought , but I will from this point forward. thank you again..
+1 on this comment. I’m a licensed electrician, and I f-ing guarantee you that better than 50% of electricians wouldn’t think of the cord. I am in a lot of electrician discussion groups and electricians will be the first to tell you that they are abusive, know it alls. I, on the other hand appreciate any opportunity to learn and grow, and that starts with humility. This is a very valuable, educational video and could potentially save lives.
So bottom line is unbond the generator when connecting to your house panel as the manufacturer recommends, but make sure you have a good cable....correct?
Make sure you have good connections all the way through from generator to your main panel. Anywhere there's a connection, there's the potential it could be loose.
If you use a single leg (120V only) generator and neutral or live gets loose you will lose all power, maybe the plug or whatever other loose connection starts arcing and catches fire too. With a two leg 240V generator if the neutral gets loose the 240V will be distributed among the different connected devices according to their power consumption, causing those with higher consumption to receive a too low voltage and those with low consumption to receive a voltage that is too high. But the neutral can also arc inside the plug or wherever it's loose and cause a fire.
Excellent video. You can never be too careful. Great job. Some would have left the other video live and done nothing. You immediately took it down when you had a problem and then had the thoughtfulness of other people to talk about it and walk us through your solution. Bravo and Thanks.
Thank you for your video. I have the exact same set up as you. And I too replaced the generator recently. I have the cable that came with the transfer switch. Only used it once. So I decided to buy a backup cable. I have it, but never opened the box. Now I will and check the connections as you showed. Regarding the bonding question. I too been thinking of this matter a lot. I’ve concluded that the outlets on board the generator are bonded for safety, however I do not believe the 30 amp twist lock for the transfer switch is bonded. If it were which 120 volt leg is it bonded to? In a 240 volt path there is no neutral. The path I believe is balanced between the 120 legs and not the neutral. Again your video was excellent and could or will save countless home and lives. Thank you for going though the effort of making this video.
Hey Paul, thanks for the feedback, I really appreciate it. Try this: with generator off and nothing plugged into it, check for continuity between the ground and neutral on one of the 120v receptacles. If the generator is neutral bonded, you will have continuity, otherwise it is in a floating config, no continuity there. If it is in a floating config, or if you modify it to be such, when you connect it to your transfer switch using the 230v cord (while generator is off), rechecking a 120v outlet should show it now bonded, because of the bond at your panel.
This was helpful, my new generator (that hasn’t even been fired up yet) is sitting outside waiting for everything else I’m needing to use it to arrive and you’re reminding me to test every aspect of it, the heavy duty cable that came today, etc before I trust any of it… Thank you
Nice job finding the problem. In my home the surge protectors are in steel boxes next to the fuse box. Yes I still have fuses on the old part of the house. I never, ever use any plastic electrical devices like a UPS, surge protector etc. I had a problem with power and it was due to a corroded aluminum wire feeding my panel. When we had a hurricane and lost power I replaced all those wires. Been good ever since.
The best whole house surge protector is the Ditek brand they have a different MOV called a thermal protected MOV. What happens during a surge most surge protectors MOV's sacrifice themselves. Which is what you want, but the problem is if you get a 2nd surge now you have no protection. Ditek because thermal protected MOV can continue to protect they don't self sacrifice. It installs easily into your main panel.
I have experienced loose connections at the generator end plug that I suspect is a result of vibration from the generator. These connections need to be checked regularly.
Very common issue on RV's that have 50a service connection. Im RV service tech electrical specialist. Old cords or old power pedistals at RV parks. For various reasons if the neutral line fails plug, cord, etc and a low resistance appliance like the hot water heater kicks on electric causes a huge imbalance on the two lines of 120 and typically fries a bunch of stuff in seconds.
Be advised with your surge protector the MOV will blow and protect on the first fault, but instead of just not passing current ( open circuit) then the surge protector goes into bypass and you have no protection which as far as I am concerned is a huge safety issue
This information is invaluable. I’m currently in the process of having a transfer switch installed and have the same generator you used in the original tutorial. Thank you for sharing this.
@@bluesriderDF bottom line was the ground in the cord was carrying the load but since they are bonded inside the panel the house never saw the issue till you separated the neutral in the gen set.
This is a fantastic analysis, and it's a really good lesson for the rest of us. I'm sorry you had to go through that, i bet you were pretty razzled until you found it it was a faulty cable!
Thanks for the story. Glad you figured it out, and glad no one was hurt. I'm sure it was a real head-scratcher. Now... to finish the explanation. When the neutral was bonded to ground on the generator (as well as at the service panel), the ground wire provided a return path for the current despite the disconnected neutral wire. So everything worked, although not as designed. When you unbonded the neutral on the generator, the ground wire could no longer provide a return path to the generator's neutral. I don't pretend to know exactly what fried your surge protectors but obviously it created an overvoltage situation. However, I think it would have been more appropriate and more helpful to title this video "Faulty Generator Cord Started a Fire!"
Thank you for the explanation. That is what I've been told as well. I know it will be nerve racking using the generator the next time I need it until I calm down.
Surge protectors are made to clamp voltage at a low enough level that your electronics aren't damaged by a very brief spike in voltage. But sustained over voltage causes the MOVs to get extremely hot. Plastic surge protector casings can melt or burn. Although the sustained over voltage situation is rare, I decided many years ago to get surge protectors with metal casings. I had seen an over voltage situation at work that melted a hole through the bottom of one of our surge protectors and burned the carpet it was laying on. Fortunately it was only the carpet directly under the hole and the rest of the carpet did not catch fire.
Do not count your bus bars as phases. They are not phases only bus bar A and bus bar B same phase. Very good content in your post. Thanks for sharing. Rest assured most of us do not think of checking the UL listed store bought extensions. Now I will.
What I have just dealt with is a dropped neutral. As pointed out already, the current tried to find another route. If it's balanced between the two hots, it could operate without too much issue. However, if it goes out of balance (and that could be the difference of one lightbulb being on or off) it changes voltage on each line,(As already pointed out). Potentially feeding 220v to your appliances and lighting. It looks like Those surge protectors detected the higher voltage, saving your tv. Bulbs can explode and tvs can start arcing, but luckily you avoided that.
I'm a roadie, and I never connect my equipment to a building's power or to a generator without first metering voltages and checking continuity (or expected lack of continuity) between ground and neutral. I've been asked by venue guys a few times why, and this video in part shows why.
You should expect to find a small AC voltage difference between the grounded and grounding conductors in any building even with the service entrance disconnect open. The utility system transformer is also grounded and uses the earth to return unbalanced polyphase medium voltage (pole voltage) current. For single phase residential areas that may be the entire medium voltage current. Any measurement with an ohm meter should show the neutral connected to ground with much less than 1 ohm of resistance after accounting for the resistance of the probes. Most ohm meters will not be able to read this resistance accurately because of the AC voltage difference. If there is substantial corrosion on copper grounding electrodes a copper oxide rectifier may also create a DC offset that only a few instruments can read the DC ohms through accurately. Reverse the probes and see if the resistance changes. In power system parlance what you call the neutral is the grounded conductor and what you call the ground is the grounding conductor. The distinction between the two is that the grounded conductor carries the net (unbalance) of the powered conductors that you would call line or hot. How much of that current appears in the grounding electrode and its conductor and how much is carried on the service entrance grounded conductor varies. In specific circumstances there may be a large current on both the utility neutral and grounding electrode caused by power system driven earth ground current unrelated to power consumption within the building of interest.
did roadie work for a bit. Volt meter and amp probe were at the top of my list. I also made a break-out lead to do amp probing of extension cords in case there was a question. (2 cord-caps wired with an extra loop on the hot leg) One stage hand argued with me that his lighting was only 150 watts and I soon learned he needed glasses because they were 750 watts each. Yeah, four of those on a 20 amp circuit will be ok, right? (for about 30 seconds)
@@oliverstreet7704 all good points nd certainly valid in ay situation. The nature of "roadie work" (first post here) is usually looking for the shaky aspects of temporary power and trying to second guess what others in the venue have screwed up. Quite often this temporary gear is well worn from being moved on a regular basis. A good visual inspection is an acquired skill in that business. So are good working habits.
I had a series arc fault that started a fire in my basement. The load was a 120V 10A steam humidifier fed from a 15A outlet through a 25ft 14ga extension cord. It ran this way for many years. The cause was a poor connection at the female end of the extension cord. The arc persisted for a long duration and it burned itself open without tripping the standard 15A breaker. It started the wall on fire. Fortunately I was able to extinguish the fire before it got out of control. The solution: I ran a new dedicated 15A AFCI circuit to a GFCI outlet mounted clear of any flammables to feed only the humidifier. Running continuous unattended high current loads through manufactured cables or extension cords is hazardous because the connections in such cheaply manufactured cables cannot be inspected and verified. Arc fault circuit protection is my new best friend. 😊 And all extension cords get side eye from me now. 😒
Oh man! Glad you caught that. I had this house built and I'm familiar with it. When you buy somebody else's place, you have no idea what they did. One thing I wish they did here was use 12ga / 20amp for more circuits, especially in the garage. That might actually be required now.
That generator bond covered up the cable's unconnected neutral. By removing the bond, there was no more neutral. All unbalanced circuit loads would get up to 220v pumped through it . Only balanced loads will get 110v.
Been browsing around looking for someone that pretty much had the same generator as me so that I could verify that I’m unbonding the same generator correctly. And just when I thought I was done I saw the end of your video and I just had to click on the next link. What’s crazy is that I also have two of their exact same power strips and one of them is a little burnt and the red led light for wire fault was on, but everything else even the outlet it was connected to was fine and it’s still working so I decided to keep the power strip and put in storage till I need it later. So now I’m going back into storage and I’m searching for that power strip and I’m dumping that and any other power strip that’s not working correctly. Thank you.
I never thought of power strips as disposable, but from what i've read, they should be replaced over time. But there's no consensus on what that time period is. Metal power strips seem to be the way to go, however.
Thanks for sharing your experience. Great information. I am wondering if the constant vibrations of the generator ended up working the screws loose over the 20 years.
Without a neutral and an unbalanced panel the leg with the biggest load will be the return for the light loads on the other leg. The less loaded leg will get the high voltage and the more loaded leg will get low voltage. The neutral takes the difference in voltage balancing the circuit. So that surge protector probably saw about 190 volts
You smoked a surge protector due to an overvoltage. The neutral was lost and then you lost the balance between L1 and L2. This causes an overvoltage on one line and undervoltage on the other. Without a neutral, the loads in your house determine which side gets more voltage. Unfortunately, that surge protector was on the lightly loaded side which allowed more voltage, and then the MOVs tried to clamp that voltage. They can only handle momentary overvoltages like a surge, but not a constant overvoltage from a floating neutral. Older surge protectors do not have thermal disconnects to deal with long term overvoltages, as they were not required by UL1449 at that time. Before you removed the duplicate bond, you had TWO separate problems, and that turned your ground wire into a neutral pathway. That went unnoticed, but could have also been dangerous because there was a voltage difference between your generator frame and any grounded j-boxes, metal conduits, and grounded appliances in your house. There should only be one N-G bond in your house at the main service panel. Any subpanels do not get N-G bonds because they already get a bonded feeder. Any time you have two or more bond connections, neutral currents will flow through the ground path and create a hazardous condition.
5:57 If I am not mistaken, your transfer switch is the first “panel” that the electricity flows through, whether running on power from the electric company or from the generator. When that is the case, your “main” breaker panel is a subpanel, and it must be wired as a subpanel is supposed to be wired by code. The big thing that must be done in a subpanel is ALL ground wires and ALL neutral wires have to be isolated from each other - they cannot share the same buss inside the panel. Seems that in your panel grounds and neutrals aren’t isolated from each other.
The load center which is energized from the PC is always the main panel. A sub panel can feed the main panel (or a portion of it) while distributing the isolated neutral and isolated grounds back to the Main panel bus bars along with the hot wires to circuit breakers. Just because the sub panel is back feeding power to the main panel does not mean the sub panel is now the main panel….
Each circuit on the transfer switch has 2 wires going into the main panel, a red and black. The red connects to the breaker you want to power. The black that was on the breaker is connected to the black from the t-switch. So power comes into main, goes to T-switch, then comes back into panel and out to the circuit in the house. There is a neutral and ground from the T-switch L14 plug that is connected to the neutral and ground bars, respectively, in the panel. These are a straight pass through from the generator. The transfer switch was made by Gen/Tran, which is now called Reliance Controls, based in California. They were owned by Generac for a time, and they still make my switch, under the name Pro/Tran. It is UL listed.
I believe you are correct, if I remember you should only have your neutral and ground bonded at the first point of disconnect, that would be your transfer switch auto or manual. ALL other panels should be wired like a sub panel. I just had to separate my main panel and add a larger ground buss.
@@bayouslots3143 - I know I’m correct, as you yourself discovered the ground and neutrals are to be separated in a subpanel. What’s unclear in this particular picture is why there are people who think the breaker panel hasn’t become a subpanel …
At first I thought this was going to be really stupid and then I learned, anybody could have done this. Only people with egos would scoff,working with com ed I might have missed it if I didn't check with meter and load. Excellent learning video.
You probably have had the neutral on that cord not functioning for the entire time and when your generator was in bonded mode the return path to the generator was provided by the ground wire on the extension cord. When you unbonded your generator you removed the ability of the ground wire to act as the neutral return. So not coincidental that unbonding the generator eliminated the neutral path and caused the issue.
So this happened to my house.. the neutral fell off the transformer. This transformer fed my home and my neighbors, we both had our AC on. My house was the first in line, and the first breaker down from the service connection went to the living room. Let’s just say it found a ground, arched through the outlet and caught the wall on fire. Been out of my home for almost 6 months as they do repairs and replace/paint everything
I'm from the UK but I believe if neutral is lost on the American system you end up with leg 1 and leg 2 appliances in series across 240v . Ok if the load on the 2 legs is exactly the same (highly unlikely) so one of the legs will end up way higher than 120v. Any MOV in a surge protector will then do its job, conduct, and catch fire.
@@user-gq2vn1xj2r Thank you. It took me a couple weeks of researching and asking questions, I was determined to get to the root cause. Definitely scary stuff.
I believe that the connections were tight from the factory, but got loose over the 20 years the cable was in service. Screws get loose over time from vibrations, so I believe that all the rough handling that the cable endured (specifically the plugs) from being dropped and dragged around made the screws loosen over time. It's a good reminder (even for myself as I haven't thought about this until now) to check all the cables that have plugs mechanically connected to them (with screws, not soldered on and potted in rubber fom the factory).
Thankyou for the reminder to check your generator cords because you can get a defective cord and things do wear out as well as the fact that terminal screws can sometimes loosen.
I am glad you're okay and that it wasn't a lot worse as, from what you said in the video it could have easily have been so much worse. This could have all been avoided it there wasn't that stupid split-phase system as there would be only one possible voltage and loss of neutral would have meant a loss of power rather than massive overvoltage and fire. If there was only 220V, which could be done, things would be a lot simpler.
I know the video is from Jan 25 and you may not get notified about this comment but I will leave it for others to see. When you do not have a neutral back to the power source in this case, the two hot legs will try making a circuit through the neutral how ever they can. In this case the MOV's in the surge suppressors were allowing the current to flow between the two hots and try to balance the load. The problem was that the MOV's in both power strips did not like the current flow through them and burned out. There is a reason a good electrician will setup a generator system to have the important systems on generator power and others like TV's and non essentials will be left out. In this case the only things that should be on a generator for a power outage is refrigerators, freezers, furnaces and well systems. Options would be lighting after that, but it should be in necessary areas like kitchens and maybe garages with the door opener. If you want to power the whole house, then I would suggest getting a whole home generator setup and if you want to go cheaper on the setup, then get a load shedding system. The only reason you should break the neutral ground bond in a generator is if the neutral at the transfer switch is using the neutral and ground connections in the main panel or at the main disconnect on the premises per NEC code 250.34(A)
I read all these comments, thanks for writing that up! It was educational, and i'm sure will help others. As you said at the end, I am using the neutral in my panel, which is why my generator is floating. A whole house generator would be nice, but don't have the funds for that and honestly, we don't really get that many power failures. Watch, now I'll get another week-long one. 😮
In the case of using an interlock kit (essentially a manual transfer switch?), does the code and/or mfg call for breaking the generator neutral/ground? Also, when and why are you required to drive a ground rod for a portable generator ?
@TheRobWay1 There is only one call for a ground rod on the generator, and that is when the generator is isolated from a main distribution panel that has no grounding. If the generator is attached to a main distribution panel that has grounding, then the cable that connects the power from generator to panel must have all wire connecting lines, neutrals, and grounding. If not connected, then you are violating NEC code for safe electrical conditions.
Thank you for this video. Just a follow up question: Even though the right thing to do with your setup was to float the neutral, do you think the fire would have still happened (regarding the cord problem) if the generator would have had the neutral bonded?
The neutral had been bonded to ground and I was using that setup without a problem. Little did I know that the ground wire was essentially acting as the neutral until I remove that bond, and then the crap hit the fan. 😱
Thank you so much! When I was running the generator at the end of the video it was in floating neutral configuration. That's how I plan to run it going forward.
Thank you for the lesson. About to install an interlock kit and buy some cables for a new generator. Will definitely be checking the connections all around.
So why would you un- bound the generator if your panel is bonded your transfer switch is grounded and your running a 4 prong generator twist lock plug that is grounded back to the panel and transfer switch?
I think after all this, I'm going to keep mine bonded. The fact is this, it might carry load between the panel and the generator. Fact is all the wires going to the generator from my panel are 6 gauge because overkill. And all the wires for neutral and ground in the generator are the same. So what's the point.
You don't. You leave it like it is from the damn factory. It will perform as intended. They are wired correctly from the factory to prevent this BS from happening.
@@ComputerFreek Exaaaaaaaaaaaaaaaaactly. Unbox it and use it as it was intended. You'll note there wasn't a big red warning card or label on the Gen that says "You must disconnect and unbond this gen before use!"
@@243wayne1 THe issue is, the factory doesn't know how you are going to use the generator. If it's sold more as a home backup, then they will probably come unbonded. But if they sell it primarily as a portable generator, then it will be bonded and then if you hook it to your house, you should unbond it. But it does beg the question as to whether it's really safer, but I guess the guys at the NEC should know best.
One of the worst things for electric service is to lose a neutral connection. It can happen anywhere between the pole, meter, or breaker panel. An aged or neglected system, storm damage, excessive corrosion, etc. can all be causes. The neutral is the return path for imbalanced loads on each side of the 120v circuits (loads are almost never balanced....turn on a toaster and it changes the balance hugely) so the side with the lesser load will take the brunt of over-voltage. I once repaired a neutral loss that occurred inside the service meter; it was a really old house and the aluminum ground/neutral corroded off the terminal. Most of the light bulbs blew and phone chargers and other small electronics caught fire. Fortunately, it didn't get worse.
So am i understanding it right that the surge protector blew because the current flowed back to the generator via the ground connection instead of the white neutral line?
A better way to explain it is that without the neutral, instead of there being approx 120v on each hot coming from the generator, one leg had an overvoltage and the other an undervoltage. The surge protector was taking too many volts. Explanation stolen from the web: "The neutral is acting as the return path for electrical current, ensuring that the current flowing out from the hot wire is effectively balanced by the current returning through the neutral, resulting in a near-zero net current in a balanced system; essentially, it helps to distribute the electrical load evenly and prevents voltage imbalances. "
@@bluesriderDFhow could current have flowed through the surge protector if the white neutral was not conducting and this was a 120 volt outlet it was plugged into? Electricity cant flow through a load with only 1 wire attached to power source unless it goes through ground wire, but sounds like your saying the one wire supplied all the power.
@@sizzelot2 hots going from generator to panel, no neutral. From panel, the circuits had hot, neutral and ground wires. If you read through some of the longer comments others have made, there are some pretty thorough explanations. I am not an electrician, I work in IT 😊
@@sizzelot All the neutrals for the house circuits are bonded together in the main panel. As long as the neutral back to the pole (or generator in this case) is there, you have 120v on each leg. If that neutral going to the pole (or gen) is removed, now you have all the circuits in the house getting 240v in series. Google images for "lost neutral wiring diagram"
I remember when, as a heating contractor the first electronic controlled furnaces appeared. I was installing one and upon testing it wouldn't fire and shut off on safety. I fiddled with the thing for over an hour and finally got on the phone and called the manfactures engineering dept. The told me to check the polarity of the black and white wire coming. Come to find out the black was the neutral and the white was the hot leg (+). I wired them backwards and let the customer know in case of any future issues. Polarity has become quite critical. The grounding when using a genset is more than confusing to the average user and has been the cause of many a mishap.
When you drop the neutral the loads on one phase are put in series with the loads on the other phase. If they aren’t balanced evenly you will get a high voltage on one phase and a lower voltage on the other. Think 240 across 2 different value resistors in series. The higher resistor will have a higher voltage drop than the lower. Same current through both.
I had a similar problem with my generator cable. In my case, one of the hots came loose inside the connector. No smoke and fire but the power kept cycling on and off (maybe some safety in my generator not sure) until I powered down and fixed the connector. I have the smaller version of this same generator. Mine came from the factory unbonded with instructions for bonding if it will be attached to a standalone panel.
I had a small power strip that I found had the hot and neutral reversed (I was getting buzzing/noise in my 40" monitor plugged into it). I had used it for decades. I opened it and swapped the wires (and tested it... and all my other strips as well, with a tester like you have).
Nice one and that was definitely it. But surprised the MOVs in the surge arrestors clamped at such relatively low voltages. But maybe being old they didn't fully clamp, hence the heat build up and didn't trip a breaker sooner. Got lucky there for sure!
We had a similar issue at work. There was a problem with the building transformer that resulted in higher voltage to one of our buildings. We had surge suppressors on our computers, and one of them had a hole burned through the bottom and a burned spot on the carpet. The surge suppressor was only a couple of years old. The MOVs generate a lot of heat if the voltage remains high. They are more intended for short spikes in voltage. Think of it this way - the MOVs in the surge suppressor short the voltage to ground if it exceeds the voltage rating. An extended short to ground will generate a LOT of heat. After I saw what happened at work, I decided to buy only surge suppressors in metal enclosures. More recently, a friend of mine had a problem with high voltage in her house because of a problem at the electric pole. Her surge suppressors saved her equipment, but the MOVs burned up. Hers had metal enclosures, so the damage was limited to the inside of the surge suppressor enclosure.
@jaygosch8705 Thank you for this excellent information. I didn't think the surge protectors were faulty, I didn't think they were designed to handle that kind of juice.
@@bluesriderDF Jay has the best explaination so far. The surge suppressors are designed to work properly with ALL wires properly connected and a soild Ground Stake at the panel. The problem was clearly the Neutral on the cord was a faulty connection and all 4 were loose. Probably slipped passed Q.C. 20 years ago and who ever thinks or able to check a cord, especially under load as the Navy did. Seldom happens but clamps come loose, breakers fail, wires break, and not always someones fault.
@@bluesriderDF During your video you seem to confuse 'ground bonded to frame' with 'bonded neutral'. You do know those are not the same? I'm not trying to be a smartass, just looking to clarify. I know you found a problem with your cable. Just because you found a problem doesn't mean you found all the problems.
@@thomabb I appreciate the feedback. The generator originally had the neutral and ground connected together, bonded. I shouldn't have said "grounds the generator to the frame." I did not use the right terms at some points (eg when I said "out of phase").
Your split phase imbalanced load could not get back to center tap on genset windings and found a path via N-G surge MOV’s. Typically surge protectors have a thermal fuse that should had taken it out of the circuit. That being said. It could had came back through you if you were a lower impedance path. Would recommend reinstalling that genset bond strap and keep a better eye on your connections and balance. Also check your connections to earth.
Thanks for bringing awareness!! Will definitely be inspecting all cables as I am currently installing a transfer switch and generator inlet at my house.
I've seen cables like that get loose after extended use, especially if the cable retainer is loose allowing the wires to wiggle at the connection. No fires yet.
Thanks for sharing. A good example of needing to check your work before applying a load. Although in this case you might have still missed it if neutral was touching terminal screw that was loose.
Thanks for the video. Sorry to hear that wire was defective! I'm wondering how to test wires other than the simple connectivity test. Test the connectivity while vigorously shaking the wire?
Is there a protector one could use to detect this between generator and house inlet to prevent frying things in the house? The RV ones appear to require a bonded neutral at the generator or they will throw a fault. Plus the pins don't line up with an L14. Pretty simple thing to go wrong and can burn your house down. Seems like there should be something out there that can detect this situation and cut power to the house.
I'm really not sure, sorry. Yeah, this is scary stuff. I will be a nervous wreck the next time we have a power failure, even though I have this all resolved and tested.
@@projectswithjw Interesting as I've heard products similar require the generator to be bonded but if connected to the house, you should unbond the generator. Is that the case on this device?
CORRECTIONS, thanks to the folks who commented below:
0:08 - Unbonding is removing the ground strap that connects ground and neutral, not ground to frame.
3:25 - The generator is a single phase, so it couldn’t run “out of phase.” Instead of 120v going to each leg, most or all of the 240v was going to one leg, and almost none to the other.
I just removed the ground wire from the plug terminal that goes into my generator and left my generator bonded. That way I can still use it around my property remotely and have the bonded ground.
Each leg always has 120v to neutral. The 240v is across the two legs without a neutral. With a missing neutral, 240v is present across the loads of the two legs in series. Since the loads will not be equal, the voltage drop across devices on each leg is different and some devices will see too high of a voltage and may burn up as happened with your surge suppressors.
@bluesrider. The 240v cable between my generator and box plugs into the generator carrying the 2 hits, ground and neutral. When the wires from the female receptacle on the generator go down to where you unbounded your Westinghouse they connect to their respective tabs, which are then bonded. What’s the difference between removing that jumper bond wire on the generator and having your transfer switch only connect the neutral, 3 wire config, and me removing the copper ground wire in the cable from the male ground pin on the plug?
I don’t have a transfer switch I’m wired into a 50 a breaker in the main panel and manually switch off the grid after the Power goes out.
(Unbonded)
For 20 years I’d been connecting my bonded generator to my main panel with no problems. After seeing a James Condon video on this topic I unhooked the cable ground at the plug. Had a power outage and no problem, but I don’t want any problems. I just don’t see the difference between what I did with the cable and unbonding inside the genny. I have an 8’ ground rod right below the main box I plug the gen into.
@@jtjones4081
That was very foolish . Now you have no ground to the generator. If there is a ground fault the circuit breaker on the generator won't see it and it will burn until the wires burn through. Not to mention various code violations.
A 120/240 generator cannot go out of phase as it only has one phase. What probably happened is loosing the neutral caused the power being consumed to find an alternate route back to the generator. Meaning that instead of 120 -N - 120. you had for example 50-N-190. Those surge protectors operate by clipping any over voltages. depending on the specific component (a metal oxide Varistor is usually used and rated around 140-150v) will cause the Protector to try to protect. IN this case the Surge it was seeing wasnt due to power issues as a fault in the wiring of the cable. Glad you found what caused it.
Thank you Matt, I appreciate the explanation 👍
Over revving will also clip them MOV's, Diodes, trans, IC and wipe out most battery chargers, computers, digital equipment etc. 130v at 65 hz starts driving shit crazy and turns the Genie into smoke
Your partially correct, You will read different voltages at the loads but keep in mind that the generator still only does 120vpk 240v p/p If you have equal loads say two identical fridges can you run them in series no neutral? Or say have 120v compressor in series with a deep freezer in the garage? Will one run and not the other?
Ahhh the age old question? Yes or no, in or out, up or down, right left, 1/0, will one burn up and not the other? Keep in mind what is in series and what is in parallel, isn't electricity fun.
@@bluesriderDFhe's on the right track but his explanation is erroneous. The lost generator neutral caused a backfeed through all the branch circuit neutrals putting 240v on your 120v equipment.
@@ianbelletti6241 No. he is spot-on.
It does not put 240V on your 120V legs, it depends on the impedances of the connected loads at any given time.
It can vary between 0V and 240V on a leg (and the converse on the opposite leg).
I did not see any errors or typos in what he stated.
Definitely a classic example of a floating neutral. A couple years back went on a service call in a late 1970s home, where the TV, DVR, DVD player and stereo system in living room smoked up so bad it set off the smoke detectors in the hallway and master bedroom after a 1500 watt electric fireplace had been running for over an hour, plugged into a different outlet on the other end of the living room. Come to find out, all the receptacles were backstab connection and part of a multiwire circuit (L1 & L2, sharing a common neutral) and the neutral burned up on a receptacle upstream, making everything downstream into a series 240V circuit and depending on the load balancing, voltages applied accross the load can range from nearly 0, to nearly 240. Also pointed out to the homeowner and corrected, the two single pole breakers controlling the multiwire branch circuit, by installing an identified handle tie to ensure that if either leg trips the entire circuit is dead, protecting anyone working on it thinking its dead when in fact one leg is still hot, evidently this wasn't required when the home was built.
This whole catastrophe could have been avoided, had article 300.13 (B) of the NEC been applied which states that for multwire branch circuits, the continuity of the grounded (neutral) conductor shall not depend on connections to receptacles, lamp holders and so forth, where the removal of such devices would interrupt continuity. What this means, is that the neutral on those receptacles should have been connected via a pigtail
I HATE backstab receptacles!!!!
Always use spec grade clamping connections, or at least use a J hook connection.
This was one of my arguments for not unbonding my generator, having more or less a redundant neutral. In the end I did unbond it and have not had any issues, but this video shows the importance of having a good solid connection all the way around.
Why did you unbind it if you were for bonding? This topic is so confusing, nobody has a definitive answer. I haven't had an issue running my generator bonded.
@@billyfowler9423
Using the ground as a current carrying conductor, bonded at both ends, is a serious code violation.
I think the biggest lesson here is to always test before you need it. After making any changes, test and verify.
Glad you weren't hurt.
Thank you Mike. The cable tested okay as far as continuity, but failed when under load. Definitely learned something here.
@@bluesriderDF That's rough. A continuity test is usually enough.
My first thought after all the troubleshooting was "why didn't you test the cable first since it's the easiest? "And then I realized I would have followed the same process as..."it's just a cable and how could THAT be the issue?"
The following is an experience I had a friend asked me to look at. What I found out I had never heard of.
When turning on several lights in the house, the house lighting would slow flicker or surge up and down, get brighter then dim. Everything checked out to be normal throughout the house, so I assumed it was a lost neutral somewhere in the house. I have years of experience in residential, commercial, and industrial electrical field's but I'm not a licensed or insured electrician and screwing with a lost neutral can burn down your house, so I recommended having a licensed and insured electrician take a look. They did. The electrician found everything was normal throughout the house also. Eventually he found the problem. It was a mixture of different brands of LED light bulbs throughout the house causing the fluctuation. My friend changed all the LED light bulbs to one brand and that fixed the problem.
Wow, that's wild.
I have the same problem. Thx for the tip.
I swear I said to myself about 10 seconds after you suggested an immediate fire, "His cord has a faulty neutral, and the ground wire previously provided neutral because they were bonded at the generator."
I'm glad you and your house are still standing to talk about it.
Thanks man. Yup, that's what happened.
there are a lot of lessons in this video. This could be a whole lesson for an apprentice or journeyman refresher course. Open neutrals are something we run into a lot and are often times at the service point. Interesting video and I am glad that you are safe!
Wow, thank you so much for your comment, I really appreciate it.
Nice detective work. Thanks for the info.
Thanks so much 👊
The surge protector did catch on fire because it had a very /low/ resistance. Not high resistance. The MOVs inside go low resistance when exposed to over voltage, and they are supposed to short out and blow your fuses. It can be dangerous supplying power from a generator as it might no be able to make enough short-circuit current to trip thr fuses.
Don't confuse neutral with ground. Ground only carries current when something is wrong. Neutral carries all the unbalanced current between L1 and L2.
That unfortunately isn't as true as you would normally hope.
With the increased use of better protective earth connects you can easily get a competition between the supply company's attempts at providing a low impedance neutral (truly reference to earth at the generators, subs, and transformers) and the parallel earthing impedances for the multipoint safety protections.
It gets worse in three phase supplied zones where the individual phase takes are unbalanced and the protective earth-neutral bonding enhances the diverted neutral current. It will depend on your generic location as to whether the local buildings and construction styles will make it more or less likely , and not forgetting 'fault' conditions.
Thank you and Phil's reply. I was beginning to think that no one had a clue about what bonding is for.
Thank you, thank you, thank you.
I have been stressing about the floating neutral question for about a month now and I am almost finished with the complete installation of my system.
You answered my questions and really gave me down to earth answers.
I'm good now.
Thanks man.
Well you just made my night. 😊 You are welcome!
"gave me down to earth answers." I see what you did there.
Interesting. Thanks for sharing. Lost neutrals and meltdowns are not something I normally associate with generator usage. I made up my own generator extension cords. After watching, I'll open them up to absolutely sure connections are still snug after 2 years...especially the neutral.
That sounds like a great plan. Thanks for posting!
I agree, I will check my cord.....
Side note: 250.30 of the NEC requires separate bonding wire to the service panel when connecting a generator in this situation if the neutral remains connected to the grid. However, if the transfer switch also separates the neutral from the grid, then the generator needs to be internally bonded.
The neutral is never connected to the grid as it's generated by the center tap of the line transformer on the pole
That is truly scary. Thanks for posting this video. Reminds everybody we should never take anything for granted.
You got that right! Thanks for commenting.
I am not an electrician, but have been doing home renovations for 30 years. I installed a 120 volt Coleman RV heat pump in my kitchen ceiling. I also installed a dedicated duplex outlet for this purpose. However, when I turned on the heat pump the first time, it ran but was noisy. So I shut it off and went to inspect the heat pump itself. The motor case was extremely hot. I troubleshooted the possibilities, and found I had connected the neutral to the neighboring breaker, so the circuit was 240 volt. OOOPS.. Five years later, by some magic, the heat pump is still working. Oversight happens to everyone, so your extension cord failure is not a surprise, but glad you figured it out. (PS: during the course of home renovations, I found many many electrical and plumbing faults, done by the "PROFESSIONALS".)
I feel like no good deed goes unpunished as they say. I did a lot of research on this ahead of time, and I really thought I had everything covered.
You are like a electrician detective. Glad it was only a couple of surge protectors that burned and not you home.
LOL, thank you! I'm hoping things are uneventful going forward!
Before you unbonded your ground at the generator, your neutral current was flowing through the ground conductor in the extension cord and the bonding jumper. So it was a related problem and unbondining your generator is correct. A ground rod would NOT have mitigated this problem even if you had connected it directly to your service entrance rod. That would have made the neutral current flow through your ground rod wires.
I agree. Thanks for posting!
When the neutral get loose like that one leg goes high, the other one goes almost to zero volts like you said on the video and everything is connected in series between the two phases. The culprit is the loose neutral connection. It can also happen on the utility side of the installation.
Yeah, there's nothing like learning in real life, LOL. This is scary stuff.
Also known as a floating neutral.... VERY bad!!!
This is why I build my own cables. I see you went the molded route and that's putting a lot of faith that it was built well.
What gets me is when you know there's a huge amount of good cabling, but all those little mistakes make it all not worth the risk :(
Well, it's UL Listed, and I like the fact that I can see the connections through the clear plugs. I've tested it and everything looks solid.
Thanks for sharing on your experience with this!!!! I'm an electrician, have installed many different types of home generator connections and transfer switches, panels , etc. But that Generator "Cord Set" some call it could be a failure that me as an electrician may not catch in my Testing, after an installation. If the home owner replaces a cord, and gets a bad/defective cord set, the result could be very bad. So important to validate/inspect/test the cord set as well. God bless
Thank you so much, I appreciate your post.
I suspect this is what happened to me. A few years ago we needed the generator, I plugged it in just like I always do and the Keurig coffee maker took a hit. Seems like we lost other electrical appliances also. Inspection of the extension cord showed a loose wire. I don't remember which one it was. But I suspect it was the neutral. I tightened all wires in both ends of the cord and everything began to work correctly. Thanks for posting this, it helps me understand what I experienced.
I guess you were fortunate too.
Thanks for taking the time to make and post this video. I had this happen to a friend of mine as well. It blew out a GFCI wall socket in the master bath, and in the master bedroom, a TV and a clock radio. Oddly, everything was isolated to his bedroom and master bath, though the open neutral was on the generator-to-transfer switch cord.
The same exact condition that you experienced occurs all too often when utility feeds coming into a building looses the neutral connection, usually at the pole due to windy conditions or sometimes in the meter pan due to corrosion. The voltages go out of balance and cause all kinds of grief. The first clue is when some lights are dimming while others are too bright and subsequently burn out. There isn’t much that can go wrong that is worse than this.
Yeah, scared us real good.
Good info. Thanks for sharing !! So glad the damage was minimal!!
Ride safe!!
If you haven’t already done so, I’d recommend a whole house surge protector. Although if it’s installed at the main panel and you are running over the transfer switch circuits only that would probably be bypassed.
One thing I’ve done at my house is install a voltmeter at where the generator goes into the transfer switch. That way I could see abnormal high voltage if my neutral was loose.
I use a generator interlock on our service entrance. Like you I added a generator status panel next to it that shows current and voltage on each leg, and frequency. The generator is electric start so the status panel includes a DC voltmeter to monitor battery voltage and verify the battery maintainer is working properly.
I also recommend installing a whole house surge protector in addition to point of use ones and also at hard wired devices.
Thanks for sharing your experience.
This is great information for the rest of us out here who have generators.
I appreciate you your comment, thank you very much.
So basically the lesson here is that it takes maybe 15 seconds with a meter to check the continuity of your cord. And probably 99% of us have never done that. We all just assumed that if we didn't make it up ourselves, that it came from the factory correctly wired. That is a dangerous assumption, more dangerous than most of us realized. Thanks buddy, I am going to go get my meter out right now.
Yeah but even then, some things only fail under a load. It was a crazy experience for sure. Thanks for posting.
One strand of any of the wires will pass a resistance check on a meter. Load testing 100%
Thank you very much, we need more people to learn how to figure things out. Everybody in they're life will need to have this type of reasoning in order to survive, can't just leave it up to somebody else all the time
Thanks again for teaching people.
Thank so much, I agree. My father and grandfather were DIY'ers, they thought me so much.
I'm an electrician retired after over 40 years in the craft. The reason that the voltage went too high on those Surge Protectors is that without an intact neutral the voltage will fluctuate with the amount of loading on each of the generator's energized conductors. The most heavily loaded side will have the reduced voltage and the lightly loaded energized conductor will have the higher voltage. The greater the difference in the loading the greater the difference in the voltage. In your case the load must have been markedly different on the 2 energized conductors and that produced a destructively higher voltage across the lighter loads which must have included those surge protectors.
Why that happened is that in most cord sets of under size 2 American Wire Gauge (AWG) all of the conductors are the same size including the Equipment Grounding Conductor (EGC). Since the Neutral Conductor of the cord had an open connection at one end it was not carrying any current. The EGC (Grounding Conductor) of the cord had been carrying the imbalance current from the Grounded (neutral) busbar of the panel to the frame of the generator. The Main Bonding Jumper of the generator windings had been carrying the unbalanced current of the different loads the rest of the way from the generators frame back to the center point of the generator's windings. Under those circumstances both energized conductors carried their portion of the load current while the Equipment Grounding Conductor (EGC) carried the difference between the current flows on each of the energized conductors.
Theoretically that is the wrong pathway for that current to return to the center point of the generator's windings but nobody consulted the electrons about our theory and they don't give a tinker's dam about what we think that they should be doing. Electric current does not take the path of least [resistance + reactance =] impedance. Impedance is the sum of the resistance and reactance to the flow of AC current. AC electric current takes all of the pathways available in inverse proportion to their respective impedances.
Once you unbonded the generator winding's electrical mid point from the frame of the generator the difference in the current flowing on the 2 energized conductors had no way back to the source. That shifts the electrical midpoint of the generators voltage away from the heavier loaded portion of the generator's windings and toward the lighter loaded end of the generator's windings.
There are devices that are usually used to protect recreational vehicles (RVs) from failures of the RV park's electrical system. One of the things that they do is disconnect the cord from the power source if the neutral conductor develops a high impedance or goes open. Using one of those plugged into the 120/240 volt plug of the Generator will disconnect the cord from the generator if either of those conditions were to develop.
Tom Horne
Thanks for the excellent explanation Tom, very thorough.
I have a question for you Tom. Would you advise against removing the bonding jumper of the generator when tied in to a residential panel that’s bonded itself ?
@joshe9518 If your panel is bonded, that's why you should remove it from the generator, so you don't have more than one N-G bond in your system, per NEC code.
So, in a nut shell, don't eff with the generator and its factory settings and staging. Leave it alone and it will do its job.
@@243wayne1 Um, what?? The National Electric Code says otherwise.
They are harder to find but I use metal surge suppressor strips instead of plastic. They contain overloads and don’t melt. I was convinced one year when as an IT professional I came into work and found over a dozen of those plastic strips burnt or damaged from a surge. Worth the extra cost and safety.
Personal experiences - the best lessons for those of us who are still learning! Thank you!
You're welcome!
Thank you for posting this video, in all honesty I have never even given the cord a second thought , but I will from this point forward. thank you again..
I appreciate the feedback. A lot of people have roasted me. I just wanted others to be aware of it.
+1 on this comment. I’m a licensed electrician, and I f-ing guarantee you that better than 50% of electricians wouldn’t think of the cord. I am in a lot of electrician discussion groups and electricians will be the first to tell you that they are abusive, know it alls. I, on the other hand appreciate any opportunity to learn and grow, and that starts with humility. This is a very valuable, educational video and could potentially save lives.
@@TheRobWay1 Wow, thank you so much!!
So bottom line is unbond the generator when connecting to your house panel as the manufacturer recommends, but make sure you have a good cable....correct?
Make sure you have good connections all the way through from generator to your main panel. Anywhere there's a connection, there's the potential it could be loose.
If you use a single leg (120V only) generator and neutral or live gets loose you will lose all power, maybe the plug or whatever other loose connection starts arcing and catches fire too.
With a two leg 240V generator if the neutral gets loose the 240V will be distributed among the different connected devices according to their power consumption, causing those with higher consumption to receive a too low voltage and those with low consumption to receive a voltage that is too high. But the neutral can also arc inside the plug or wherever it's loose and cause a fire.
Excellent video. You can never be too careful. Great job. Some would have left the other video live and done nothing. You immediately took it down when you had a problem and then had the thoughtfulness of other people to talk about it and walk us through your solution. Bravo and Thanks.
Second comment. I wired my own cable but haven’t been unlucky enough to have to use it yet. Going to check behind myself now. Thanks again
@@mindsablank8061Thanks for the comments !
Agree. Nice video @bluesriderDf. I'm an EE (PE) and this is one of the best plain-english explanations I've seen on this topic.
I'm also glad the old video went back up, as it was very helpful too.
Thank you for your video. I have the exact same set up as you. And I too replaced the generator recently. I have the cable that came with the transfer switch. Only used it once. So I decided to buy a backup cable. I have it, but never opened the box. Now I will and check the connections as you showed. Regarding the bonding question. I too been thinking of this matter a lot. I’ve concluded that the outlets on board the generator are bonded for safety, however I do not believe the 30 amp twist lock for the transfer switch is bonded. If it were which 120 volt leg is it bonded to? In a 240 volt path there is no neutral. The path I believe is balanced between the 120 legs and not the neutral. Again your video was excellent and could or will save countless home and lives. Thank you for going though the effort of making this video.
Hey Paul, thanks for the feedback, I really appreciate it. Try this: with generator off and nothing plugged into it, check for continuity between the ground and neutral on one of the 120v receptacles. If the generator is neutral bonded, you will have continuity, otherwise it is in a floating config, no continuity there. If it is in a floating config, or if you modify it to be such, when you connect it to your transfer switch using the 230v cord (while generator is off), rechecking a 120v outlet should show it now bonded, because of the bond at your panel.
On a 120v outlet, the neutral is the larger slot, so you would check continuity from there to the ground.
This was helpful, my new generator (that hasn’t even been fired up yet) is sitting outside waiting for everything else I’m needing to use it to arrive and you’re reminding me to test every aspect of it, the heavy duty cable that came today, etc before I trust any of it… Thank you
Good plan! Thanks for posting.
Nice job finding the problem. In my home the surge protectors are in steel boxes next to the fuse box. Yes I still have fuses on the old part of the house. I never, ever use any plastic electrical devices like a UPS, surge protector etc. I had a problem with power and it was due to a corroded aluminum wire feeding my panel. When we had a hurricane and lost power I replaced all those wires. Been good ever since.
Thanks you for posting. I definitely prefer steel over plastic. Everything works until it doesn't, right?
The best whole house surge protector is the Ditek brand they have a different MOV called a thermal protected MOV. What happens during a surge most surge protectors MOV's sacrifice themselves. Which is what you want, but the problem is if you get a 2nd surge now you have no protection. Ditek because thermal protected MOV can continue to protect they don't self sacrifice. It installs easily into your main panel.
Thank you for everything!
I’m glad you and your family are safe 🙏
Same to you!
I have experienced loose connections at the generator end plug that I suspect is a result of vibration from the generator. These connections need to be checked regularly.
Wow, who knew? I really like the new cable. Because everything is soldered, sealed, and I can see it.
I wonder if it started off tight, and the generator running loosened it up? Good diagnostics!
That is probably the case.
Not likely. The female end is the one that had the loose neutral which plugs into the transfer switch.
@@chrish7927 It was the male side that was loose.
@@bluesriderDFI just watched the video again and it was definitely the female end that pulled apart and the connectors came right out of it.
@@chrish7927Oh, my bad then, sorry.
Great info. Glad the family is safe.
Much appreciated, thank you!
Very common issue on RV's that have 50a service connection. Im RV service tech electrical specialist. Old cords or old power pedistals at RV parks. For various reasons if the neutral line fails plug, cord, etc and a low resistance appliance like the hot water heater kicks on electric causes a huge imbalance on the two lines of 120 and typically fries a bunch of stuff in seconds.
Holy smokes! Literally!
As others have said, thanks for sharing the story and glad everyone is ok. Sharing these experiences helps others.
Thanks so much. That's why I posted it, I'm glad it's getting some views.
Be advised with your surge protector the MOV will blow and protect on the first fault, but instead of just not passing current ( open circuit) then the surge protector goes into bypass and you have no protection which as far as I am concerned is a huge safety issue
This information is invaluable. I’m currently in the process of having a transfer switch installed and have the same generator you used in the original tutorial.
Thank you for sharing this.
@@robertalvarez8128 Thank you for the feedback! This is why I put up the video.
So un-bonding at the generator, removing the neutral and ground tie, was not the problem, correct?
Correct. The neutral was disconnected in the gen cable. The ground wire in the cable masked this issue until the generator was unbonded.
@@bluesriderDF bottom line was the ground in the cord was carrying the load but since they are bonded inside the panel the house never saw the issue till you separated the neutral in the gen set.
This is a fantastic analysis, and it's a really good lesson for the rest of us. I'm sorry you had to go through that, i bet you were pretty razzled until you found it it was a faulty cable!
Thank you! I had frayed nerves for a while, especially the next time I had a power failure and needed to use ir.
Interesting. Thank you for taking the time to make this video, it is valuable information for others to watch out for.
Glad it was helpful!
Thanks for the story. Glad you figured it out, and glad no one was hurt. I'm sure it was a real head-scratcher.
Now... to finish the explanation. When the neutral was bonded to ground on the generator (as well as at the service panel), the ground wire provided a return path for the current despite the disconnected neutral wire. So everything worked, although not as designed. When you unbonded the neutral on the generator, the ground wire could no longer provide a return path to the generator's neutral. I don't pretend to know exactly what fried your surge protectors but obviously it created an overvoltage situation.
However, I think it would have been more appropriate and more helpful to title this video "Faulty Generator Cord Started a Fire!"
Thank you for the explanation. That is what I've been told as well. I know it will be nerve racking using the generator the next time I need it until I calm down.
Surge protectors are made to clamp voltage at a low enough level that your electronics aren't damaged by a very brief spike in voltage. But sustained over voltage causes the MOVs to get extremely hot. Plastic surge protector casings can melt or burn. Although the sustained over voltage situation is rare, I decided many years ago to get surge protectors with metal casings. I had seen an over voltage situation at work that melted a hole through the bottom of one of our surge protectors and burned the carpet it was laying on. Fortunately it was only the carpet directly under the hole and the rest of the carpet did not catch fire.
Do not count your bus bars as phases. They are not phases only bus bar A and bus bar B same phase.
Very good content in your post. Thanks for sharing. Rest assured most of us do not think of checking the UL listed store bought extensions. Now I will.
From a UK perspective, I'd say they were anti-phase, so were 'different'. Each of the systems have their strengths and weaknesses ;-)
What I have just dealt with is a dropped neutral. As pointed out already, the current tried to find another route. If it's balanced between the two hots, it could operate without too much issue. However, if it goes out of balance (and that could be the difference of one lightbulb being on or off) it changes voltage on each line,(As already pointed out). Potentially feeding 220v to your appliances and lighting. It looks like Those surge protectors detected the higher voltage, saving your tv. Bulbs can explode and tvs can start arcing, but luckily you avoided that.
Yes, I was incredibly fortunate.
I'm a roadie, and I never connect my equipment to a building's power or to a generator without first metering voltages and checking continuity (or expected lack of continuity) between ground and neutral.
I've been asked by venue guys a few times why, and this video in part shows why.
You should expect to find a small AC voltage difference between the grounded and grounding conductors in any building even with the service entrance disconnect open. The utility system transformer is also grounded and uses the earth to return unbalanced polyphase medium voltage (pole voltage) current. For single phase residential areas that may be the entire medium voltage current. Any measurement with an ohm meter should show the neutral connected to ground with much less than 1 ohm of resistance after accounting for the resistance of the probes. Most ohm meters will not be able to read this resistance accurately because of the AC voltage difference. If there is substantial corrosion on copper grounding electrodes a copper oxide rectifier may also create a DC offset that only a few instruments can read the DC ohms through accurately. Reverse the probes and see if the resistance changes.
In power system parlance what you call the neutral is the grounded conductor and what you call the ground is the grounding conductor. The distinction between the two is that the grounded conductor carries the net (unbalance) of the powered conductors that you would call line or hot. How much of that current appears in the grounding electrode and its conductor and how much is carried on the service entrance grounded conductor varies. In specific circumstances there may be a large current on both the utility neutral and grounding electrode caused by power system driven earth ground current unrelated to power consumption within the building of interest.
did roadie work for a bit. Volt meter and amp probe were at the top of my list. I also made a break-out lead to do amp probing of extension cords in case there was a question. (2 cord-caps wired with an extra loop on the hot leg) One stage hand argued with me that his lighting was only 150 watts and I soon learned he needed glasses because they were 750 watts each. Yeah, four of those on a 20 amp circuit will be ok, right? (for about 30 seconds)
@@oliverstreet7704 all good points nd certainly valid in ay situation. The nature of "roadie work" (first post here) is usually looking for the shaky aspects of temporary power and trying to second guess what others in the venue have screwed up. Quite often this temporary gear is well worn from being moved on a regular basis. A good visual inspection is an acquired skill in that business. So are good working habits.
I had a series arc fault that started a fire in my basement. The load was a 120V 10A steam humidifier fed from a 15A outlet through a 25ft 14ga extension cord. It ran this way for many years. The cause was a poor connection at the female end of the extension cord. The arc persisted for a long duration and it burned itself open without tripping the standard 15A breaker. It started the wall on fire. Fortunately I was able to extinguish the fire before it got out of control.
The solution: I ran a new dedicated 15A AFCI circuit to a GFCI outlet mounted clear of any flammables to feed only the humidifier.
Running continuous unattended high current loads through manufactured cables or extension cords is hazardous because the connections in such cheaply manufactured cables cannot be inspected and verified.
Arc fault circuit protection is my new best friend. 😊
And all extension cords get side eye from me now. 😒
Oh man! Glad you caught that. I had this house built and I'm familiar with it. When you buy somebody else's place, you have no idea what they did. One thing I wish they did here was use 12ga / 20amp for more circuits, especially in the garage. That might actually be required now.
That generator bond covered up the cable's unconnected neutral. By removing the bond, there was no more neutral. All unbalanced circuit loads would get up to 220v pumped through it . Only balanced loads will get 110v.
Exactly.
Been browsing around looking for someone that pretty much had the same generator as me so that I could verify that I’m unbonding the same generator correctly. And just when I thought I was done I saw the end of your video and I just had to click on the next link. What’s crazy is that I also have two of their exact same power strips and one of them is a little burnt and the red led light for wire fault was on, but everything else even the outlet it was connected to was fine and it’s still working so I decided to keep the power strip and put in storage till I need it later. So now I’m going back into storage and I’m searching for that power strip and I’m dumping that and any other power strip that’s not working correctly. Thank you.
I never thought of power strips as disposable, but from what i've read, they should be replaced over time. But there's no consensus on what that time period is. Metal power strips seem to be the way to go, however.
Thanks for sharing your experience. Great information. I am wondering if the constant vibrations of the generator ended up working the screws loose over the 20 years.
It was actually loose at the side that connects to the transfer switch
Thanks for this video. Very easy to follow. Will check my cords and generator with that meter.
You're very welcome
Without a neutral and an unbalanced panel the leg with the biggest load will be the return for the light loads on the other leg. The less loaded leg will get the high voltage and the more loaded leg will get low voltage. The neutral takes the difference in voltage balancing the circuit. So that surge protector probably saw about 190 volts
Makes sense
You smoked a surge protector due to an overvoltage. The neutral was lost and then you lost the balance between L1 and L2. This causes an overvoltage on one line and undervoltage on the other.
Without a neutral, the loads in your house determine which side gets more voltage. Unfortunately, that surge protector was on the lightly loaded side which allowed more voltage, and then the MOVs tried to clamp that voltage. They can only handle momentary overvoltages like a surge, but not a constant overvoltage from a floating neutral.
Older surge protectors do not have thermal disconnects to deal with long term overvoltages, as they were not required by UL1449 at that time.
Before you removed the duplicate bond, you had TWO separate problems, and that turned your ground wire into a neutral pathway. That went unnoticed, but could have also been dangerous because there was a voltage difference between your generator frame and any grounded j-boxes, metal conduits, and grounded appliances in your house.
There should only be one N-G bond in your house at the main service panel. Any subpanels do not get N-G bonds because they already get a bonded feeder.
Any time you have two or more bond connections, neutral currents will flow through the ground path and create a hazardous condition.
Great explanation, thanks!
5:57 If I am not mistaken, your transfer switch is the first “panel” that the electricity flows through, whether running on power from the electric company or from the generator. When that is the case, your “main” breaker panel is a subpanel, and it must be wired as a subpanel is supposed to be wired by code. The big thing that must be done in a subpanel is ALL ground wires and ALL neutral wires have to be isolated from each other - they cannot share the same buss inside the panel. Seems that in your panel grounds and neutrals aren’t isolated from each other.
Mskes Sense
The load center which is energized from the PC is always the main panel. A sub panel can feed the main panel (or a portion of it) while distributing the isolated neutral and isolated grounds back to the Main panel bus bars along with the hot wires to circuit breakers. Just because the sub panel is back feeding power to the main panel does not mean the sub panel is now the main panel….
Each circuit on the transfer switch has 2 wires going into the main panel, a red and black. The red connects to the breaker you want to power. The black that was on the breaker is connected to the black from the t-switch. So power comes into main, goes to T-switch, then comes back into panel and out to the circuit in the house.
There is a neutral and ground from the T-switch L14 plug that is connected to the neutral and ground bars, respectively, in the panel. These are a straight pass through from the generator.
The transfer switch was made by Gen/Tran, which is now called Reliance Controls, based in California. They were owned by Generac for a time, and they still make my switch, under the name Pro/Tran. It is UL listed.
I believe you are correct, if I remember you should only have your neutral and ground bonded at the first point of disconnect, that would be your transfer switch auto or manual. ALL other panels should be wired like a sub panel. I just had to separate my main panel and add a larger ground buss.
@@bayouslots3143 - I know I’m correct, as you yourself discovered the ground and neutrals are to be separated in a subpanel. What’s unclear in this particular picture is why there are people who think the breaker panel hasn’t become a subpanel …
Thank you for sharing your experience. By sharing this you may have helped others. Kudos to you sir!
That's what I hope for. Thanks for posting 👍
At first I thought this was going to be really stupid and then I learned, anybody could have done this. Only people with egos would scoff,working with com ed I might have missed it if I didn't check with meter and load. Excellent learning video.
I really appreciate your comment, thank you. I've been roasted here by some but that's OK because a lot of people are now aware of this danger.
You probably have had the neutral on that cord not functioning for the entire time and when your generator was in bonded mode the return path to the generator was provided by the ground wire on the extension cord. When you unbonded your generator you removed the ability of the ground wire to act as the neutral return. So not coincidental that unbonding the generator eliminated the neutral path and caused the issue.
Or maybe it worked loose over time, not sure. Either way, definitely a bad situation.
So this happened to my house.. the neutral fell off the transformer. This transformer fed my home and my neighbors, we both had our AC on. My house was the first in line, and the first breaker down from the service connection went to the living room. Let’s just say it found a ground, arched through the outlet and caught the wall on fire. Been out of my home for almost 6 months as they do repairs and replace/paint everything
SIX MONTHS?!?! That suuucks!!!! So sorry. No one got hurt I hope. Hopefully you get your home back soon.
I'm from the UK but I believe if neutral is lost on the American system you end up with leg 1 and leg 2 appliances in series across 240v . Ok if the load on the 2 legs is exactly the same (highly unlikely) so one of the legs will end up way higher than 120v. Any MOV in a surge protector will then do its job, conduct, and catch fire.
One of the greatest youtube videos I have watched!!!! Good for you for finding the root cause.
@@user-gq2vn1xj2r Thank you. It took me a couple weeks of researching and asking questions, I was determined to get to the root cause. Definitely scary stuff.
I believe that the connections were tight from the factory, but got loose over the 20 years the cable was in service.
Screws get loose over time from vibrations, so I believe that all the rough handling that the cable endured (specifically the plugs) from being dropped and dragged around made the screws loosen over time.
It's a good reminder (even for myself as I haven't thought about this until now) to check all the cables that have plugs mechanically connected to them (with screws, not soldered on and potted in rubber fom the factory).
I will never know if they were tight at the beginning. But i'm never going to use a cable like that again. Soldered and molded from now on.
Thanks! I’m going to check my cable tonight and my shore power cable also.
Thanks for this video. It definitely made me go "Huh." I think I'm going to check all my connections now.. 😊
Thankyou for the reminder to check your generator cords because you can get a defective cord and things do wear out as well as the fact that terminal screws can sometimes loosen.
Thanks for sharing! Glad everyone is OK!
I appreciate that, thanks.
I am glad you're okay and that it wasn't a lot worse as, from what you said in the video it could have easily have been so much worse.
This could have all been avoided it there wasn't that stupid split-phase system as there would be only one possible voltage and loss of neutral would have meant a loss of power rather than massive overvoltage and fire. If there was only 220V, which could be done, things would be a lot simpler.
Thanks so much. Yeah this scared the bejesus out of me! I don't think I'll ever relax while a generator is running in the future.
I know the video is from Jan 25 and you may not get notified about this comment but I will leave it for others to see. When you do not have a neutral back to the power source in this case, the two hot legs will try making a circuit through the neutral how ever they can. In this case the MOV's in the surge suppressors were allowing the current to flow between the two hots and try to balance the load. The problem was that the MOV's in both power strips did not like the current flow through them and burned out. There is a reason a good electrician will setup a generator system to have the important systems on generator power and others like TV's and non essentials will be left out. In this case the only things that should be on a generator for a power outage is refrigerators, freezers, furnaces and well systems. Options would be lighting after that, but it should be in necessary areas like kitchens and maybe garages with the door opener. If you want to power the whole house, then I would suggest getting a whole home generator setup and if you want to go cheaper on the setup, then get a load shedding system. The only reason you should break the neutral ground bond in a generator is if the neutral at the transfer switch is using the neutral and ground connections in the main panel or at the main disconnect on the premises per NEC code 250.34(A)
I read all these comments, thanks for writing that up! It was educational, and i'm sure will help others. As you said at the end, I am using the neutral in my panel, which is why my generator is floating. A whole house generator would be nice, but don't have the funds for that and honestly, we don't really get that many power failures. Watch, now I'll get another week-long one. 😮
In the case of using an interlock kit (essentially a manual transfer switch?), does the code and/or mfg call for breaking the generator neutral/ground? Also, when and why are you required to drive a ground rod for a portable generator ?
@TheRobWay1 There is only one call for a ground rod on the generator, and that is when the generator is isolated from a main distribution panel that has no grounding. If the generator is attached to a main distribution panel that has grounding, then the cable that connects the power from generator to panel must have all wire connecting lines, neutrals, and grounding. If not connected, then you are violating NEC code for safe electrical conditions.
Thank you for this video. Just a follow up question: Even though the right thing to do with your setup was to float the neutral, do you think the fire would have still happened (regarding the cord problem) if the generator would have had the neutral bonded?
The neutral had been bonded to ground and I was using that setup without a problem. Little did I know that the ground wire was essentially acting as the neutral until I remove that bond, and then the crap hit the fan. 😱
thank you
similar problem happened with me because of a loose neutral on a generator plug years ago.
Marvelous video! Thank you. I assume your generator is still not bonded to ground?
Thank you so much! When I was running the generator at the end of the video it was in floating neutral configuration. That's how I plan to run it going forward.
If you have a floating neutral transfer switch or a switched neutral transfer switch determines the bonded or floating neutral setup on the generator.
Thank you for the lesson. About to install an interlock kit and buy some cables for a new generator. Will definitely be checking the connections all around.
Glad it was helpful!
So why would you un- bound the generator if your panel is bonded your transfer switch is grounded and your running a 4 prong generator twist lock plug that is grounded back to the panel and transfer switch?
@@KevinKarl-o8y Because NEC code requires there be only one neutral ground bond. There's lots of videos which explain it better than I can.
I think after all this, I'm going to keep mine bonded. The fact is this, it might carry load between the panel and the generator. Fact is all the wires going to the generator from my panel are 6 gauge because overkill. And all the wires for neutral and ground in the generator are the same. So what's the point.
You don't. You leave it like it is from the damn factory. It will perform as intended. They are wired correctly from the factory to prevent this BS from happening.
@@ComputerFreek Exaaaaaaaaaaaaaaaaactly. Unbox it and use it as it was intended. You'll note there wasn't a big red warning card or label on the Gen that says "You must disconnect and unbond this gen before use!"
@@243wayne1 THe issue is, the factory doesn't know how you are going to use the generator. If it's sold more as a home backup, then they will probably come unbonded. But if they sell it primarily as a portable generator, then it will be bonded and then if you hook it to your house, you should unbond it. But it does beg the question as to whether it's really safer, but I guess the guys at the NEC should know best.
One of the worst things for electric service is to lose a neutral connection. It can happen anywhere between the pole, meter, or breaker panel. An aged or neglected system, storm damage, excessive corrosion, etc. can all be causes. The neutral is the return path for imbalanced loads on each side of the 120v circuits (loads are almost never balanced....turn on a toaster and it changes the balance hugely) so the side with the lesser load will take the brunt of over-voltage. I once repaired a neutral loss that occurred inside the service meter; it was a really old house and the aluminum ground/neutral corroded off the terminal. Most of the light bulbs blew and phone chargers and other small electronics caught fire. Fortunately, it didn't get worse.
So am i understanding it right that the surge protector blew because the current flowed back to the generator via the ground connection instead of the white neutral line?
A better way to explain it is that without the neutral, instead of there being approx 120v on each hot coming from the generator, one leg had an overvoltage and the other an undervoltage. The surge protector was taking too many volts. Explanation stolen from the web: "The neutral is acting as the return path for electrical current, ensuring that the current flowing out from the hot wire is effectively balanced by the current returning through the neutral, resulting in a near-zero net current in a balanced system; essentially, it helps to distribute the electrical load evenly and prevents voltage imbalances. "
@@bluesriderDFhow could current have flowed through the surge protector if the white neutral was not conducting and this was a 120 volt outlet it was plugged into? Electricity cant flow through a load with only 1 wire attached to power source unless it goes through ground wire, but sounds like your saying the one wire supplied all the power.
@@sizzelot2 hots going from generator to panel, no neutral. From panel, the circuits had hot, neutral and ground wires. If you read through some of the longer comments others have made, there are some pretty thorough explanations. I am not an electrician, I work in IT 😊
@@sizzelot All the neutrals for the house circuits are bonded together in the main panel. As long as the neutral back to the pole (or generator in this case) is there, you have 120v on each leg. If that neutral going to the pole (or gen) is removed, now you have all the circuits in the house getting 240v in series.
Google images for "lost neutral wiring diagram"
I remember when, as a heating contractor the first electronic controlled furnaces appeared. I was installing one and upon testing it wouldn't fire and shut off on safety. I fiddled with the thing for over an hour and finally got on the phone and called the manfactures engineering dept. The told me to check the polarity of the black and white wire coming. Come to find out the black was the neutral and the white was the hot leg (+). I wired them backwards and let the customer know in case of any future issues. Polarity has become quite critical. The grounding when using a genset is more than confusing to the average user and has been the cause of many a mishap.
Found that to be CRITICAL when using twinning control on two 120 volt furnaces running in combined mode.
Wild that a caboe you've been using without incident just suddenly isn't wired right. Circumstances changed and made a huge difference in this case.
When you drop the neutral the loads on one phase are put in series with the loads on the other phase. If they aren’t balanced evenly you will get a high voltage on one phase and a lower voltage on the other. Think 240 across 2 different value resistors in series. The higher resistor will have a higher voltage drop than the lower. Same current through both.
Would a whole house surge protector have helped in my situation? I'm thinking probably not.
@@bluesriderDFprobably not, they need the nuetral to do any work.
@@bluesriderDFit absolutely would have
I had a similar problem with my generator cable. In my case, one of the hots came loose inside the connector. No smoke and fire but the power kept cycling on and off (maybe some safety in my generator not sure) until I powered down and fixed the connector. I have the smaller version of this same generator. Mine came from the factory unbonded with instructions for bonding if it will be attached to a standalone panel.
I had a small power strip that I found had the hot and neutral reversed (I was getting buzzing/noise in my 40" monitor plugged into it). I had used it for decades. I opened it and swapped the wires (and tested it... and all my other strips as well, with a tester like you have).
Wow, maybe replace that strip with a new one.
Nice one and that was definitely it. But surprised the MOVs in the surge arrestors clamped at such relatively low voltages. But maybe being old they didn't fully clamp, hence the heat build up and didn't trip a breaker sooner. Got lucky there for sure!
Wifey and I were jumpy for a week after this. I thought the whole place was gonna go up!
We had a similar issue at work. There was a problem with the building transformer that resulted in higher voltage to one of our buildings. We had surge suppressors on our computers, and one of them had a hole burned through the bottom and a burned spot on the carpet. The surge suppressor was only a couple of years old. The MOVs generate a lot of heat if the voltage remains high. They are more intended for short spikes in voltage. Think of it this way - the MOVs in the surge suppressor short the voltage to ground if it exceeds the voltage rating. An extended short to ground will generate a LOT of heat. After I saw what happened at work, I decided to buy only surge suppressors in metal enclosures. More recently, a friend of mine had a problem with high voltage in her house because of a problem at the electric pole. Her surge suppressors saved her equipment, but the MOVs burned up. Hers had metal enclosures, so the damage was limited to the inside of the surge suppressor enclosure.
@jaygosch8705 Thank you for this excellent information. I didn't think the surge protectors were faulty, I didn't think they were designed to handle that kind of juice.
@@bluesriderDF Jay has the best explaination so far. The surge suppressors are designed to work properly with ALL wires properly connected and a soild Ground Stake at the panel. The problem was clearly the Neutral on the cord was a faulty connection and all 4 were loose. Probably slipped passed Q.C. 20 years ago and who ever thinks or able to check a cord, especially under load as the Navy did. Seldom happens but clamps come loose, breakers fail, wires break, and not always someones fault.
Excellent work tracking this down. Good due diligence on your part.
Thanks!
Do you have a 3 pole or 4 pole transfer switch? That makes a huge difference in how your generator needs to be configured.
3 pole. It's configured correctly, just had a bad cable.
@@bluesriderDF During your video you seem to confuse 'ground bonded to frame' with 'bonded neutral'. You do know those are not the same? I'm not trying to be a smartass, just looking to clarify. I know you found a problem with your cable. Just because you found a problem doesn't mean you found all the problems.
@@thomabb I appreciate the feedback. The generator originally had the neutral and ground connected together, bonded. I shouldn't have said "grounds the generator to the frame." I did not use the right terms at some points (eg when I said "out of phase").
thank you.. this is a must watch video if you own or plan to own a portable generator
Thanks for posting!
Your split phase imbalanced load could not get back to center tap on genset windings and found a path via N-G surge MOV’s. Typically surge protectors have a thermal fuse that should had taken it out of the circuit. That being said. It could had came back through you if you were a lower impedance path. Would recommend reinstalling that genset bond strap and keep a better eye on your connections and balance. Also check your connections to earth.
It seems like having 2 paths to ground is "safer" even though not to code.
Thanks for bringing awareness!! Will definitely be inspecting all cables as I am currently installing a transfer switch and generator inlet at my house.
This is exactly why I posted it. Thank you!
I've seen cables like that get loose after extended use, especially if the cable retainer is loose allowing the wires to wiggle at the connection. No fires yet.
Good video here. I'm going to buy a cable like that and will check the connections before use.
Thank you! Glad it was helpful.
Thanks for sharing. A good example of needing to check your work before applying a load. Although in this case you might have still missed it if neutral was touching terminal screw that was loose.
Thanks for the video and especially your troubleshooting process. It should be helpful for many viewers.
Thanks!
Thanks for the video. Sorry to hear that wire was defective! I'm wondering how to test wires other than the simple connectivity test. Test the connectivity while vigorously shaking the wire?
Use a simple volt ohm meter. Confirm there is continuity from each lug on the extension cable on both ends.
Fyi I have had APC do the same and received recalls years later after I threw them out.
These specific ones weren't subject to that recall. Nevertheless, I can't blame the poor thing, I think it got hit with almost 200v.
lost neutral. and ck cords cause they do discolor oxidize. very good and scary video. great job thankyou
Thank you sir 👍
Is there a protector one could use to detect this between generator and house inlet to prevent frying things in the house? The RV ones appear to require a bonded neutral at the generator or they will throw a fault. Plus the pins don't line up with an L14. Pretty simple thing to go wrong and can burn your house down. Seems like there should be something out there that can detect this situation and cut power to the house.
I'm really not sure, sorry. Yeah, this is scary stuff. I will be a nervous wreck the next time we have a power failure, even though I have this all resolved and tested.
Power watchdog can do that. PWD50EPO for 50 amp. PWD30EPO for 30 amp model.
the issue is that at lower power, the wire might have been leaning on the contact and give a false positive. This would fail at high current.
@@projectswithjw Interesting as I've heard products similar require the generator to be bonded but if connected to the house, you should unbond the generator. Is that the case on this device?