Does my 13kW Offgrid Solar System require Grounding? Is it Grounded?
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- เผยแพร่เมื่อ 15 ส.ค. 2021
- I follow Mike Holt and ABYC for grounding considerations:
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Every video includes some form of paid promotion or sponsorship. Some links on this youtube channel may be affiliate links. We may get paid if you buy something or take an action after clicking one of these. My videos are for educational purposes only. Information is subject to change/update at any time. Electricity is DANGEROUS and can kill. Be smart and use common sense :)
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Will, can you please give us a visualization of different grounding procedures? Correct vs incorrect. Grid tie vs off grid.
seconded
Thirded
fourthed
Ditto
Same, please
The comprehensiveness of this video makes it a true standout. I have struggled to explain my particular situation, and I now understand that I need to describe other situations that would require earth grounding, how and why may be the missing piece. Truly excellent work!
Your videos are a wealth of infomation , thanks for taking the time to educate us newbies , I specialy appreciate your approach to saftey and in depth explanations .You helped me build my first off grid sep up for my cabin few years ago and its still going strong .
Keep up the awesome work mate !!
Thanks for these great videos! We just bought a 12 kw system on Sat for our off grid home and these videos couldn't have come at a more opportune time!
It's unfortunate that the National Electrical Code uses the term grounding and grounded. I was a member of the NEC section for many years and there has always been confusion. Many of us believe that the current terminology should be canned and use the terms earthing and bonding to help eliminate confusion. Many other countries use this terminology and it is much simpler.
I agree! I prefer using the term earthing, but I know that's not the appropriate term. It's unfortunate the terminology can be so confusing.
Good to know.
It needs to go! Those who know will pick up on the changes it fast enough. The rest of that don’t can start learning properly.
And while you're at it... get rid of your imperial dumb system... 😉
@@honumoorea873 The metric system is soo much easier than the imperial system. I have a degree in chemistry so I have been using the metric system since the 1950s. It is great. I can't even imagine trying to do scientificl calculations in the imperial format. That being said, the imperial system is so ingrained into our culture that I can't see it being changed in the foreseeable future. Need a calculator that converts metric/imperial/fractions. What a mess.
Part 2 Grounding Update: th-cam.com/video/X3QA9T_O1g0/w-d-xo.html
Update: this system will never pass an inspection and never needs to. It is Offgrid and there is not a single permit required for connecting a battery to an inverter, and using a couple of panels laying on the ground. People are trying to reference NEC?? Why? This inverter isn't even listed. Sure it's compliant and certified, but it would still fail inspection. And that's fine. I'm not connected to grid (besides back up battery charger which isn't grid tie. It's a battery charger). And I only care about safety and that's it.
Original pinned comment:
Oh and I'm adding ac supply at the input on it's own breaker today (and programming it to only use the battery charger. Not bypass!). That's why I said it has true earth ground in one of my given examples.
When this system is supplied by a true earth ground ac circuit, I do not need to separate the grounds and neutrals on my panel because the transfer switch will be open, and the output of this inverter will not act as a sub panel supply. This is because the input only supplies a battery charger in my configuration. If I am using it as a UPS (which requires programming it as such), and I have a large dedicated breaker supply from my sub panel, (which I will not do), then I will need to separate ground and neutrals. That would make a separate connection, and it is not isolated. When the ATS inside the inverter is connected only to the battery charger, it is isolated. But still susceptible to high voltage if a ground loop was created.
If it was not grounded when not connected to ac input, that is fine. There are plenty of standalone systems without grounding. Such as an RV electrical system with inverter when not connected to shore power. Same thing.
So it really depends on how you use it. If you are using it not as a solar power system, and instead as a stand-alone UPS, then I could see why you do not want to bond the ground and neutrals at the ac output. But that is the only exception I can think of.
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Contact Information:
I am NOT available for personal solar system consult! If you wish to contact me, this is my direct email: williamprowsediysolar@gmail.com
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FTC Disclosure Statement and Disclaimers:
Every video includes some form of paid promotion or sponsorship. Some links on this youtube channel may be affiliate links. We may get paid if you buy something or take an action after clicking one of these. My videos are for educational purposes only. Information is subject to change/update at any time. Electricity is DANGEROUS and can kill. Be smart and use common sense :)
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Will, are you sure the setting for utility charging vs ups really switches the neutral? A switched neutral tends to be fairly expensive and I’d be surprised if this kind of sophistication is built it. I would have guessed the neutrals (AC in and out) were always bonded to each other. Would be interesting to test this with a multimeter.
You are right. I really enjoy your Channel.
Ciao
I think of a UPS as when the solar/battery is a backup for the grid. The other option - and what I'm thinking of doing in my setup is to have solar/battery as the primary with the grid as the backup. I believe that if I'm doing it in that way that I have to have a dedicated ground for the AC subpanel which is going to be in a solar shed/out-building ... I've slept a time or two since I delved into the NEC looking this stuff up though - I'm going to have to re-read it to remember the details on grounds and panel bonding however.
Hi, could you please make a new video with "schemas" and explanation? It will be very clear for all of us. Please.
@@kmil2010 actually some are not. You always need to check. These inverters are for Offgrid use only when not in ups or backfeed mode. They have some inverters that are hybrid, and the connections are obviously different. But yes I should verify with multimeter
Great videos, I learn a lot. Grounding is a complex topic. I don't have the answers but I have some thoughts. NEC 250.32 deals with grounding outbuildings. Since 2008, grounding electrodes are required at outbuildings like your garage causing multiple earth grounding electrodes contrary to the older philosophy of avoiding ground loops in the grounding conductor systems.
One more thing you need to understand about AC grounding is "Bonding" this provides a path for the electricity to trip the breakers from a grounded short circuit. Bonding is usually provided by a ribbon in the back of your breaker box that goes from ground to neutral. If you have multiple boxes, only bond your ground to the neutral in the box closes to the incoming service and remove the bonding connection in all boxes feeding the main box. Make sure grounds are in place to all wiring to other boxes. This provides only one path for a large surge or lightning.
Great job explaining the shock hazard. Also GFIC breakers are a great way to save your life. All my shop outlets are fed buy GFIC breaker.
I think I need to revisit my ground setup. Thanks Will.
I have now watched the video.
Surge protection is a wonderful idea on the DC side - do not oversize it, match it closely to the maximum open-circuit potential of the solar array. Get the ground connection wired as straight as possible to a good earth ground (and this can be separate from the service entrance - like at a ground-mounted array) but bonded to other ground rods if inside a structure.
You are correct in not adding more ground points than at the service entrance of a building. Ground loops are to be avoided, chased down, and eradicated. They can cause all kinds of obscure issues. An SPD will not cause a ground loop.
The DC side, being under 60 volts, is likely going to be a Class 2 circuit under the National Electrical Code (NEC)
Solar arrays have the advantage of being inherently current-limited.
Batteries are not, so over-current protection is required.
Neither are going to be much of a shock hazard at 48 VDC.
thanks!
Your knowledge of electrical code is impressive, James Alles. I felt like a first-year electrical student, again, just reading your comment. Are you an instructor?
@@jayspell179 no, that is something that I missed. I became aware of the low-voltage aspect of the code working for Simplex on Fire Alarm systems in the 80s. I suppose I did do a little teaching. thanks
Wow I don't think I'm ever going to be able to figure out these grounding theories.🙂
I enjoyed reading your comments. What happens when the PV arrays are wired in series and produce voltages of around 400V DC? The latest solar inverters can take up to 6kW input @450V DC up to 20A. If I had two 5000W inverters wired in parallel and eight 50V Canadian solar panels (VOC 49.6V, IOC 13A) wired in series serving each inverter, what might be the earthing / grounding implications of such an install?
@@fredflintstone1428 earthing / grounding stays the same. Conductor insulation becomes critical - 600V is needed. check your local codes, it is now high voltage, and an entirely different animal.
I've never analyzed the grounding like you. But I've just followed the instructions. But I have thought about adding another grounding rod.
Thank you Will for expounding on this ground discussion going on on your site. I have learned a lot from Mike's lecture and from your comments. Now I need to go unhook my ground rod from my array!! This is way more complicated than most people think especially when you add in lightning.
Are you sure you want to do that? I don't think what he is saying is the same as a grounded array. if you put up a tv antenna outside I'm sure you would ground it. if lighting hit the array it will most likely enter the ground at the grounded array
I have read many comments and happy to see so much interest and concern over safety and desire to become more educated on it. Please do so!
One of the issues, imo, is our words.... take ground, neutral and line. We all use ground" wrong at times. Many times I say ground when I mean desired return current path, which in houses is called the neutral.... which is (typically) strapped at the box to earth ground.
And speaking of ground loops with myself and other saying how they are bad... when the electric company safely has created ground loops with your neighbor's earth ground rod.... all depends on where the loops are.
I'm happy to see these discussions : )
Use Good sense... Common sense? def common these days... might not be the best! An example of a play with words intentionally when the understanding of "common sense" to make good decisions is not properly conveyed. Same as more recent technical words like ground etc...
Will does good with follow up and education, ya'll do the same now, ya hear?
Dude ur channel Came on my recommendation, glad i found...ur videos are awsome and well explained..
William you are so informed thank you
You do a very good presentation on all of your videos keep up the good work thanks..👍👍
Fault current travels back to the source, not to the earth. Mike Holt’s Grounding versus Bonding videos are great source of information. I have to stay up with the NEC every 3 years. He has been teaching for over 40 years. As a side note Will, if it was not a stand alone system, or if you were to use this system for a home back up in an emergency power outage, through an interlock kit, make sure your Neutrals and Grounding conductors will be separated in this Square D panel. 6/4 cable would go back to the interlock breaker. Also, only one neutral conductor is allowed per terminal. Otherwise you will have an objectionable currents flowing on all metal parts of your electrical system - dangerous condition to have. I keep finding this in people’s homes when someone would add a sub panel.
The grounding and grounded (neutral) conductors have to be connected only in one point in the house - at the main breaker panel.
Very good point if I use an interlock kit. I would absolutely separate the grounds and neutrals in the panel. That would be very dangerous if I did not. I am glad you watch Mike Holt! He is fantastic!
I was going to bring up bonding. I know in a city connection you only bond at the main breaker box and not at the subpanels. As I understand the concept of bonding is to give the electricity a return path so as to not ground out an entire system, how does that work in an off grid scenario? Do you still do bonding at the main box? Or is it a ground that is used? This is a great discussion going on here and bringing up very good points that I was curious about.
I'm trying to figure out my solar system sure glad I found the videos thank you Will.
I'm taking in so much information trying to figure out what stuff to buy and everything. It's overwhelming and now I'm finding out about grounding and it's really overwhelming I don't know anything about it.. and even your great explanation I couldn't figure out. On my new system that's similar to this one but I'm only going to have one inverter for now 120. I'm not going to have any AC input because I don't have any AC input anywhere I'm completely off grid. I was considering wiring my generator into that AC input. I guess I still don't know anything about grounding. I'm going to have to listen to the video again and again. I think you said if you have AC input you don't need ground because it's already in the AC input wires that sounds logical. I'll read it again if my comment doesn't make any sense I'll delete it.. I didn't know anything about grounding until today. Wow it's very confusing.
I am confused. A diagram would have been nice to include in the video. The lightning diagram alone taught me a lot!
Please do a video on grounding considerations for solar panels on both roof mounted and ground mounted arrays.
I swear you’re reading my search history. I was just looking up how to ground these systems
I agree completely, but I heard rumors for questionable sources that a Tesla charger might be very finicky in this type of circut. I was hoping to see how that worked out today. Great tutorial thanks.
Good information. Appears that sub panels need to have isolated neutrals so faults go back to main panel. Grounding electrodes for lighting protection.
Is that considered a sub panel since it is all by it's self? Or a "main panel"? I was wondering if it would need to have separate neutral and grounding bars.
Excellent! I feel slightly responsible! Something I didn't realize when watching other vidy (off grid title?) that you had an earth ground elsewhere. Absolutely correct, grounds loops are dangerous and can cause electrical problems with certain equipment.
Bottom line, follow local code, mfg instructions. Any exposed conductive surfaces that encloses a potential (voltage) should be PROPERLY grounded to prevent shock. exceptions like double insulated code etc, ya need to check code. And yea, seen double insulated fail.
And my apologies, didn't realize you DID have a proper grounded case (breaker box) enclosure.... thought off grid.
Thanks,
Ken
I did not understand that either . If it was said during the video . I missed it . Be safe out there folks ... Gubs
That was important to note that you had an established ground elsewhere already. I would also consider 110.26 as a good practice(batteries below equipment)
Been there done that! Cleaning rack mounted equipment and bumped the conduit with my hand and damp rag while my neck was touching the earth grounded rack = a very big shock! (220v 50Hz) Burned my neck and locked me up until my coworker bumped me with his foot to break my neck from the rack. Turned out during install the power wire had the insulation skinned while being pulled through the conduit. 🥵
I built my own system and I’m totally confused, it always works better when you show exactly how you’re hooking up a ground and where and why! 😳
I’ll definitely look into the links. Thanks
May I also suggest NFPA 99 ... just skim contents for meat ya want.... things will start to click and looking into the subject as you said will help us all be safer : )
A local grounding to your own earth spike would make sense in case of an outage of commercial power, which would cause you to lose their ground reference. But in such a case, you’d also need to have an Earth-Neutral Bridge (the single point where it’s all bonded), which flips automatically between commercial power ground and your own local ground, depending on if the commercial provider is up or down.
Surge protection on for each fuse box on the PV side is definitely a plus. I use 500V SPD’s.
No... loss of utility input does not interrupt earth grounding at the meter. Only way to interrupt that would be to disconnect the earth conductor feeding the ground rods at the residence ot the pole.
@@SuperVstech Not my experience… I have SMA PV inverters, and every time we had a loss of mains AC, we had a PE (potential earth) fault that caused the inverters to stop making power because they assumed grid failure, even with the micro grid present. An Earth-Neutral bridge bonding that also included a local ground spike fixed this.
@@DJMT-Africa If there wasn't a neutral to earth ground bond at the the main disconnect, then that was your problem, and it would have been in violation of code. Downstream panels/subpanels from that point onward must have their grounds and neutrals separated, unless it falls under some exception.
@@davereichert It could be that code in my country is different than in the U.S.
Mike Holt is great. I used to use his videos in my Electrical Trades Classes. For those people on here that want drawings, they should go look at Mike Holt. He does great drawings.
If you wanted to add a 240v shock prevention device, look into adding a residual voltage device (RVD)
The larger the connector cable to the source from the output board, the smaller the earth fault loop impedance, making it trigger faster under fault conditions. You are correct, you wouldn't want to connect to a house earth system, some (most) do not have sufficient equipotential bonding and this allows for transient currents on the earth conductor, and we are not just talking milliamps.
Will, Great point. A similar question relating to those solar generator/power stations. I believe they are not truly grounded. The A/C output runs on floating neutral. What if, when the A/C charge input is connected. Would the power station be grounded during the time through the A/C input cable? Now, would the ground pass through to the A/C output if there were output load plugged in the A/C output jack?
I agree with you on grounding. My car doesn't have a earth ground yet has a large power inverter
I spy with my little eye... some new Bluetti cables to the bottom right... excited to see your take on what they're up to.
Good explanation.
Thanks for Mike Holt reference. His video was helpful. There appears to be a lot of confusion about purpose of ground rods. Potential for more damage instead of safety. Seems like electrical practices are evolving. A bit scary with folks installing their own solar and emergency generators tied to residences without complete understanding.
Hey Will. Very informative videos! I’ve watched many of your videos on lithium batteries but I wondered if you have reviewed later generation lead acid batteries called crystal lead batteries? Not as good as LiFePO4 but reportedly much improved on flooded lead acid batteries. Could they be a low budget option worth considering?
@will do more grounding vidoes. Start from the beginning. Been searching so few videos on this.
I'm just a layman on the subject but I'm glad your warning people about adding extra grounds. The grounds all have to be bonded together at the same potential otherwise you are giving lightning a dangerous path through your home.
Edit: also ground bonds need very heavy wire or flashing and short runs to be effective from my understanding.
Unless you are using a single load against inverter, you want to have everything properly grounded possibly with GFCI. Otherwise a fault somewhere can cause ground loop and what would be grounded is e.g. a hot wire - then all what should be ground is suddenly "hot" against the earth, and this becomes a very dangerous setup. This is not a theoretical example, I touched a place which should be true ground on friend's off-grid powered house, then kept swearing for several minutes, then spend hours to debug how the hot wire got shorted to the ground - the root cause was a mouse chewing the wire insulation, where the wire came to contact with steel rod to basement, and so far, all ground over the house was suddenly hot against the earth.
Absolutely you never want two earth ground with one system for the ground loop reasons you stated. I did not realize you had an AC input from your house. Many inverters will bond the neutral to the input AC when they switch to line power. Does the AC input ground common to your solar ground? If so you may want on oversized ground wire back to your house and it’s ground rode. Thanks again for your great videos.
Very helpful.
One more thing you need to understand about AC grounding is "Bonding" this provides a path for the electricity to trip the breakers from a grounded short circuit. Bonding is usually provided by a ribbon in the back of your breaker box that goes from ground to neutral. If you have multiple boxes, only bond your ground to the neutral in the box closes to the incoming service and remove the bonding connection in all boxes feeding the main box. Make sure grounds are in place to all wiring to other boxes. This provides only one path for a large surge or lightning.
Thanks Will. Not many people talk about grounding system for the solar system and I’m glad you did. I plan to install a Growatt SPF 5000ES hybrid off grid solar inverter in my RV Bus in Bangkok, with Lifepo4 battery bank, and solar panels. This inverter will take solar power or take AC shore power to charge batteries and convert battery DC to 220Vac output to power Dometic Aircon and TV, etc. So here, I have input ground terminal when I take 220Vac shore power. My question is do I need to connect output ground for the AC output or should I leave it unconnected (open) ? If it is needed, where would this AC ground connected to in the vehicle ?Hope you could help explain.
You are absolutely correct..!! It is clear you either studied your ass off self-taught or took engineering because you're always spot on!
Thank you sir
Perfect!!! If anyone disagrees with anything he said here go back and listen to it over and over and then study electrical engineering and electrical theory and you will then understand that everything that was said is spot on. Thank you Will.
Great presentation and explanation! Keep up the great work and posting videos you're saving equipment and you're definitely saving people for some nasty shocks.
thanks for the explanation will... just wondering, how about join those aux and true ground rods in parallel in one point? does that gives you a "one big ground"?
Title says does my “offgrid” need a ground but you are saying it has ac input. What if there is no ac grid input then what?
On my steel boat, I have a separate 24V lithium battery just connected to my mpp 3k inverter charger. I run the DC bus floating, with a 1 meg ohm resistor between the minus and the central grounding point. This way, I have the added safety of a floating system, and prevent static charge from building up on my DC bus. All Protective Earth conductors end in a central grounding point connected to the hull, just behind the isolation transformer. Shore power Earth is connected to a parking connection on the isolation transformer. When the boat is on the hard the shore power earth must be connected to the hull to prevent having a large steel structure that is unbonded. Marine Electrics in a Nutshell.
I appreciate this info. I'm 100%off grid and I was curious if I should have a earth ground connected. I bought a grounding rod but have never hooked it up. I felt like it was a complete closed system and didn't believe I actually needed one.. I have a 5kw eco-worthy hybrid inverter. Connected to my camper breaker box. I also have a inverter generator hooked up to my system to charge/bypass also I have 12 solar panels.. so... Should I use my ground rod?? Thank you
Code requires separate grounding electrodes for sub panels in outbuildings. You bring across 4 wires from the primary panel to the sub (L1, L2, N, GND), and you do not bond GND to N at the subpanel. That is to avoid current loops. But the remote subpanel DOES get it's own grounding electrode which is then connected to the ground bus bar in the sub panel and the ground pulled from the primary. A subpanel adjacent to the primary panel does not require its own grounding electrode, because the path to the primary is so short. So the question here is how far away is that sub panel from the primary. Even IF in the same building.
The sub panel in this situation is feef from the inverter. It's not a sub panel of the grid connected system. The only ground connection between this system and the grid feed system will be with the grid supplied feed to the inverter, if and when that happens.
I'd like to see a video on the pv power disapation.
On the subject of grounding. I have seen varying opinions on whether or not to ground the PV Array (I mean the PV frame NOT ground to inverters etc.) to Earth Grounding rod. You may want to do a video on this.
Oh good idea. Some panels, specifically CIGs, should never be grounded. That would be an interesting video.
I'd love a video on that,
I'm off grid, and run a 12v dc system with a only on when in use 3000w stand alone inverter, I'm still clueless as to whether an earth electrode is needed on the AC side can someone please explain, do I earth my solar controller? Or do I bond these to negative, battery etc?
Your point about lightning strike damage in your domestic system makes good sense but this seems to be dismissed when it comes to the Marine system, in favour of grounding. Which I “get”. But it raises a question in my mind: Given the greater exposure to lightning strike risk in the marine environment, do you think it would be wise to fuse marine grounds to protect the vessel from nearby strikes?
Thanks for another great video, Will. Regarding the solar arrays, their frames still need to be grounded to an earth rod, correct? For an array that is say 100 feet from the house, is there any need to carry that ground along with the positive and negative wires (i.e 3 conductors) to the house?
Hello Will, I have just discovered your videos and will be devouring them over the next while. Thank you for posting them!
I have a situation that as a non - electrician has me confused, and I am hoping maybe you might have an answer for me.
I am currently in the California desert in my solar powered cargo trailer/RV conversion. I am an astrophotographer, and spend my winter far out in the desert looking for dark skies. I have 4-325 watt Panasonic solar panels on the roof and 3-300 amp hour Lifeblue batteries for 900 watts total. The charge controller is a Midnight 150, and the charger/inverter is a Magnum 2000. The system was originally installed in my 5th wheel RV about 6 years ago by a very reputable solar company that specialized in RV installations. They have moved on and no longer do installations on RVs, so I can't talk to the people who actually installed it.
I recently moved the solar system from the 5th wheel RV to the current cargo trailer/RV conversion. Grounding to earth in an RV is not practical of course, and nothing on the solar system has been grounded to the frame. I had read that the panel, inverter, and charge controller should all be grounded to the frame, yet they weren't by the original installers. The team that installed my system had installed solar systems in about 3000 other RVs before mine, so I doubt if they just "forgot" to ground the solar components to the frame. I have to think it was intentional. So when I moved the system to the current trailer, I didn't ground anything either. So far all is working great, with 4 120 volt and 4 12 volt circuits. Only the fridge 120 volt circuit is not on a GFCI. My 120 volt Samsung home fridge specifically says not to put it on a GFCI protected circuit.
So my question is probably obvious: Should I be grounding anything to the frame of the RV? I used all metal outlet boxes, and they are all on internal walls. The outlet, and the box itself are grounded with a pigtail to the ground wire that goes back to the panel.
As a non - electrician, I have a hard time understanding why I would ever want to send electricity into the metal frame of an RV. This seems crazy to me, and a recipe for a serious shock. It seems like I now have a closed electrical loop with the panel. Why would I want to send electricity to the frame of the RV, under any circumstances?
As an aside, when I was a kid I stepped off a poorly grounded RV just after the rain had stopped. The step was metal, and I was barefoot and wet. I can only remember screaming and being frozen in place for a second or two before passing out and fortunately falling away from the step and breaking the ground. For a few hours I couldn't walk, and both my ankles were really sore. Within a few more hours I was fine. I suspect it would have killed me in a few more seconds if I had not passed out and broken the connection. It was a really terrible experience, and I don't want to relive it because I made a grounding error. But intentionally sending electricity into the RV frame just seems like the last thing I would want to do. Isn't an electrified RV frame what shocked me in the first place? Any advice much appreciated!
I'm in a small cabin and also wondering this.
Will, be very careful discussing marine "grounding" as it can get tricky and lead to ALOT of corrosion for any metal touching the water. Stray current for marine is a big deal.
Very true
Yeppers, sacrificial anodes is an interesting subject for others who are curious about this. Best
This is an area where even qualified marine technicians can get it wrong. Be very cautious about offering advice.
@@gregoryyount6907
And every boat is different. Wood, fiberglass, steel or aluminum hull and composition of below water line hardware. Then you have “under protected, over protected and the just right. Where will it spend most of the time fresh, salt or brine. Types of anode metals, bond or not to bond and bond to what? Neutral switch over to ground, isolation transformers, equipment current leakage. Oh the list goes on. It’ can be a science. Wrong gets expensive.
And land electricians think they got it rough Lol!
Check out the victron unlimited PDF for some basic marine grounding advice: www.victronenergy.com/upload/documents/Wiring-Unlimited-EN.pdf
ABYC and this book is where I get my info on marine systems from: www.amazon.com/Boatowners-Mechanical-Electrical-Manual-4/dp/0071790330/ref=asc_df_0071790330/?tag=hyprod-20&linkCode=df0&hvadid=312176357948&hvpos=&hvnetw=g&hvrand=3157251246000314898&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9030754&hvtargid=pla-333901114316&psc=1&tag=&ref=&adgrpid=60258871137&hvpone=&hvptwo=&hvadid=312176357948&hvpos=&hvnetw=g&hvrand=3157251246000314898&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9030754&hvtargid=pla-333901114316
I love it that you read and understand the manual. That's distressingly rare.
Would like for you to test or give your opinion on the EMP Shield product to protect your equipment from pulse power surges.
I have a single grounding rod connected to bare copper wire that runs to all my pv and inverter generator panel etc. in an outbuilding that feeds my RV. This is only for lightning protection and I have no AC input. Did I do it wrong?
EXCELLENT VIDEOS
Please provide some visualization on this topic. I have seen an end to end Inverter/Electric Sub-panel/Battery setup video and the gentleman there grounded the whole system with a true grounding electrode. Basically a separate grounding bus bar in the subpanel which is connected to inverters as well as true ground electrode outside.
Once again, awesome information, Will! You quite adeptly answered my question on your previous video. Looking forward to learning more about earth grounding and bonding to neutral situations for off grid systems.
what about the panels? should they be grounded and bonded to each other? ( the framing)
Very interesting stuff about the "ground loop". And I have a question. My house has a ground for the sockets (with those metal rods in the ground at the corner of the house) and a separate ground (another metal bar at the opposite corner of the house, as it happens...) for the tv cable. Is that wrong? I am assuming the shield on the antenna plug at the tv is connected to the power ground. Maybe not. Am I in danger? Thanks!
Electrical codes should require all the grounding rods to be "bonded" together (i.e., there should be a direct ground wire connection between all grounding rods, which should also be no further than 16 feet apart).
You mention the bus bars are on opposite sides of the house, but that's probably fine as long as they share the same grounding rod or the grounding rods are properly bonded. If you want some piece of mind, you could trace the connection leaving the TV cable bus bar and check that it connects back to the service ground.
Grounds need to be bonded at the rods. Delicate electronics are not where bonding should occur. If the potential of your antenna ground is better than your ac ground, your entire/most of home grounding system will attempt to pass through your tv. By bonding the rods, both should have nearly equal potential and surge/emf (why you need a coax ground) will go to shortest path vs path of least resistance.
What a great community! Thank you all for trying to help me understand this better.
The antenna ground is something I did myself to get rid of EMF interference and I can tell you that is NOT connected to the mains ground. But I do wonder if TVs will connect the mains ground to the antenna ground (shield).
I need to do some better research on this. Also, this is in Europe, on a 240V connection. Some things (codes) might differ.
One more detail: the cable tv on my house (which goes to multiple tv sets) is NOT coming from outside the house. There is a fiber coming in with both internet and digital tv signal and it goes to this box that outputs internet and cable tv...
Bonding Will, everything that is not the earth connection is a bond, not a ground. We use grounded bus bar in large incoming, high voltage vaults, as well as places like server roms to bond equipment to earth.
The NEC requires you to bind neutral and ground on the secondary of a separately derived system (transformers, solid state inverters, etc.). The reason for this is because the primary and secondary are physically separated, therefore the grounding connection does not transfer. You should bind the primary and secondary grounds (exclude the primary neutral because it is bound with the ground upstream).
But what if the Secondary is NOT connected to the onshore grid panel? if you add a ground (no longer free floating) then you may create a ground loop or have a gradient problem even though you may not think they will transfer. 30 sec and 5 min portion of this video.
One thing to always consider if isolating, is peripheral equipment ground (accidentally or otherwise). Just an AC unit sitting on a poured pad gets a surprising amount of earth ground into the housing.
Always appreciate your thoughts Karl. Thanks
Good point. I'll measure it.
@@WillProwse Was there anything there? Just curious.
Hi Will. Thanks for the tech tips. I have a question, My pv is over vaulting my inverter, But only when windy. The Panels are in series, with a combined voltage of 73 V and the inverter is 100v max.
We have a old lead acid off grid system. Way before all this new stuff. Just had a lightning bolt fry our inverter last night. Guess it's time to switch over!
Should there be a neutral to ground bond screw in the sub panel box or no ?
You are a wealth of knowledge in solar generation systems. However, this video was like another language. I’m sure the more advanced people could follow all you said. Me, not so much. I do understand ground to some degree. I understand how earth ground rods and such work with AC electricity. I was looking for help with the correct way to protect my small 4 panel system. My concerns are lighting protection for the panels. How and if I need to ground the wiring. How to connect my inverter to ground. That sort of thing. I will search your other videos.
Thank you….
Hi there, thanks, please connect ac input (utility power), and make a video to us....very nice..keep going.
I do have my panels on their own grounding for the panel frames and dc lines are fused incase something tries to send more amps through the dc input lines like a failed shorting inverter that backfeds ac to the panel frames.
Hi Will, I have a cuestion? I install a inverter powmr is 230, 24v 3000W off grid when I check the power in the output lines, one give me 90v and the other line 170. I conect the ground I install a ground route outside the storage.
Great Video.
I got 1 question and i cant seem to find anything related to this...
I have a large amount of 36v lithium batteries but i can not find any video regarding solar charger controller that can deal with these batteries, any help would be great.
Thanks.
I have a Xantrex Freedom Sw 3012 inverter charger, 4-6 volt batteries
and two 160 watt solar panels. How much more solar power
can I add to this setup. Thanks and Keep up the great work.
Excellent points, however, in places as Florida which has more than a million lightning strikes yearly it is very important to have lightning dissipators the bigger and more the better to make the system invisible to electrons Flying in both directions.
Can confirm, had my house growing up struck twice and the street a ton of times.
I can also confirm. Central Florida has widespread lightening almost every day. It’s unreal.
@@veryinteresting591 Central Florida was where I grew up! First off of OBT down the road from Gator Land and then out in Clermont. Looking back it was intense!
Thank you for the video report.
One thing I haven't seen in any solar vids on youtube is do you ground to your chassis in a pickup truck caps house battery solar setup with inverter that's not tied into the start battery
I thank you for your sight .
Im building a 48v off grid cabin. Im using two 48v grow watt with three 48v 100 ah lifepro4 in a server cases. Im looking at 24 used 250 watt 12v solar panels going to run 4 panels in series and 6 strings in parallel . Would like to get your advice on the system im building.
Will could u show us how to connect( AC which is used to charges up a car)
Do you have a video on grounding of solar inverter charger systems in RVs?
This now raises my own questions. Is it possible I can send you a YT link to a video of my setup with my current ground configuration, get your feed back?
Extremely clear and concise. Thanks again for sharing. Have a great week.
I've never been more confused about grounding and bonding after stopping here.
I'm looking to disconnect my utility and have an inverter run my house, the inverter has the earth and neutral bonded at its output, i would like to run the inverter inplace of utility at the panel so would i have to remove the ground rod? It's confusing me.
GREAT VIDEO! WAY TOO AMBITIOUS FOR ME RIGHT NOW. JUST HAVE A QUESTION ON THE SOK 206 AMP. CAN I USE THAT WITH 2 SAN TAN SOLAR 250W PANELS FOR MY TRUCK CAMPER BUILD TO RUN A FRIDGE/FREEZER, LIGHTS, FAN, SMALL TV AND TO CHARGE UP PHONE, TABLET, LAPTOP, INSTANT POT ? WHAT CONTROLLER AND INVERTER DO YOU RECOMMEND?
I just purchased Will's Mobile Solar book. I like it but the very small font size makes it very difficult to read for my old eyes.
DC grounding vs AC grounding: AC is part of an array (usually) and needs to be grounded as a “reference point to be at same potential as generator ground) DC is a relative concept by excellence and grounding one pole just introduces all kind of issues that can actually be detrimental to your system and possibly your life.
So do I disconnect the earth ground in my midnite solar combiner box or leave it in place when I hook my solar panels to my inverter
you mentioned a marine application. If you are at sea and have a solar system with a gen backup and an inverter providing onboard 110/230 v to ship systems how is a ground obtained?
Great video, but I had a question about these inverters. I went on their website and found that these are “off grid” inverters. What is this “AC input” that you refer to in your video? Is that for AC charging?
They have many types of inverters, I think the ones Will has are "hybrid". You have 120V in from the grid yes. That can be used to carry loads or charge batteries when the solar array isn't producing. You can choose what power to use for the load side of the inverter... give priority to the solar and batteries or the grid etc... depends what your goal is. Lots of people just use these things as a type of online UPS for critical circuits and the batteries are just there if the grid fails. One of the inverters cuts out the need for transfer switches and is flexible on where it gets energy ... arrays, generators, the grid - everything but rubbing two sticks together. I've powered/charged mine with a step up transformer using the dual alternators in my truck (36V @50amps step up)
Depends on what type you buy. I have these hybrid off grid inverters and I can use it completely off grid with a generator as a back up or connect it to the grid if the battery bank is depleted and no sun.
I haven't watched the video yet.
1. *Lightning protection.* a system is more likely to survive if it is isolated from ground.
2. *Safety Ground* The protections of grounding an appliance chassis can now be handled by the newer technology of a Ground Fault Circuit Interrupter (GFCI).
I will not be grounding my system, as any 120VAC load will run through some type of GFCI. I do the same for portable engine/generator sets.
If anyone's system is to be installed permanently on a structure, building codes may apply depending on the jurisdiction.
Your Authority Having Jurisdiction (AHJ) trumps anything I just said.
System with isolated neutral (ungrounded neutral), or IT system, will have different behaviour, than normal system with grounded neutral. Especially, if it fitted with GFCI's. IT electric systems are used in industry, and must have special electronic equpment to control wire insulation integrity and resistance (relative to ground). Also, these systems requires to use 2-pole breakers - for both phase and neutral conductors. And this is not compatible with standard US domestic distribution panels. So, in order to stay within Code, it is easier to use standard system with grounded neutral. Even, if this system is completely independent from AC grid, except grounding "network" within household (grounded service neutral + local grounding rods or Ufer grounding + connections to various tubes, like water mines).
What about a solar set up in a vehicle how do you protect against lately and does the system need grounded?
I have a question, is that gray power panel a main panel or a sub panel? As a main I have no problem with it,just it has no main shutdown in it. If it’s a sub panel the grounds and neutral should be separated not bound together. What you are saying is right, one grounding point in the main panel box. But you can have more than one ground from that main box. Hear we have to have at less two a two ground rods or a ground rod and be bounded to the water pipes.
Technically one grounding rod will not comply with NEC. You can have many as long as they tied together.
My plan was to ground solar panels and use ac in on inverter as the inverter wireing ground? Let me know should i run the ground from solar as well?
I'm a little confused on earth grounding my setup. My DC circuit is referenced to earth ground at the negative terminal of the battery bank. I reviewed a Victron document that, if I read it properly, indicated earth grounding at the negative battery terminal was good practice. I tied in my home's AC earth ground for that purpose. The inverter's earth ground terminal is also tied to it, as recommended in the manual. The solar panels are not grounded and are tied directly to the charge controller PV inputs (fused). The charge controller's battery output is tied to the battery bank, and thus the earth ground there. This seemed like a proper setup (single earth ground, no loops) and the DC and AC sides are using the common house earth ground. Is this setup a bad idea? Will seems to be indicating that I do not want the earth ground on the DC side.
Just installed an axpert max 7.2kw, and as soon as it switches some internal relays while powering on, the house goes dark. Had to remove the input ground wire for it to run. Im assuming the inverter switches the neutral to ground internally 🤷♂️
In the manual it states the pv array must not be grounded to it as well..
A little off subject but what can I do to protect my RV solar system from electromagnetic pulse? Maybe others would like to know about that too.