Super tear down. there is another very important difference. I was told by an old fellow of a well known German relay manufacturer: Its the chemistry of the contacts. While AC contact do not have this arc so much, DC contacts have to withstand a longer duration arc, so the contacts of an AC would not last and even worse they could weld together if switching a high load, where they are supposed to separate. So never do use AC breakers for DC, otherwise they could catch fire!
Nice to see them open, i learned about that only a year ago or so; I could not find DC ones so been using 2 AC breakers,25 Amp each, for a year now on my 60 VDC solar system, up to 32 Amps; i switch them off manually, only, sometimes several times a day ; it's impossible for the current to go over 32 amps, that is the MAX, so it's not expected that they trip on their own, ever, that is not why they are there; they are there because i need to manually disconect them ( solar panels from the MPPT/batteries ) when i need to adjust the MPPT voltages; this seldom happens; i expected them to not last, but they still work perfectly; cost me 2 or 3 euros each; i use 2 of them, 25A each, in parallel; amazingly they never burned and still worl fine; they are in a place that if they start smoking, or on fire, it does not matter, nothing to burn nearby; i would not do it, otherwise.
You can use AC breakers perfectly safely on DC, but you need to make sure that: 1. The voltage is not exceeding 50V for a 230/400V breaker 2. The breaking capacity (Icu) is at least 4500A (4,5 kA), this means it has a large enough arc extinguishing chamber. 3. If the breaker is *directly* connected to a large battery bank (more than 200 Ah) use a breaker with Icu=6000A (6kA) 4. If the breaker is *directly* connected to a very large battery bank (more than 500 Ah) use a breaker with Icu=10000A (10kA) 5. If the breaker is connected to another breaker whose Icu is 6000A, you can use an Icu=4500A breaker or a Icu=6000A breaker. 6. If the breaker is connected to another breaker whose Icu is 10000A, you can use an Icu=6000A breaker, an Icu=10000A breaker *but not an Icu=4500A breaker* This is because larger batteries can supply higher short circuit currents because the internal resistance is lower. On many US-made DC/AC breakers you can see they are rated for AC at 250V and DC at 50V, which is why this works. DC arcs are a problem only above 50V. Most welders have an open circuit voltage of 85V, for that reason. *Also I highly advise AGAINST using breakers with only a magnetic trip (unless you are using them for the intended application that is powering MOTOR ONLY loads), as it is possible that they won't trip on medium overloads that are not enough to trigger the magnetic trip. This can cause damage to wiring.*
+MrOpenGL Some really useful information there thank you. I think I pointed out in the video that there wasn't much to distinguish between the different types on the inside. However I was very conscious that some people may take that to mean ac breaker = dc breaker. I was cautious in my statements quite deliberately. It's worth noting that I run a twelve volt system - although my panels run at ~35-45v so everything is below the limit you point out. Again thanks for your input.
Thanks. You did a good video nonetheless!! :-) I would also point out that the breaking capacity is also relevant for *FUSES*. You have to choose the correct fuse not only based on voltage and nominal current, but also on breaking capacity (that is also rated in kA or A). That's why you have for instance 5x20mm glass fuses that are empty, filled with sand or with a ceramic body that's also filled with sand. The empty one has less breaking capacity than the one filled with sand, which in turn has less breaking capacity than the ceramic one. Personally I would never use blade type fuses where you would need a breaker of Icu=6000A or more. The gap they open when they fuse is too little and there is no protection against an arc, as the sides are open and the body is made of plastic. ANL fuses are better, but the best bet if you don't want to use circuit breakers and you would need a breaker with more than 10000A breaking capacity are HRC (usually in 10x38mm format up to 32A). The advantage of HRC fuses over other types is that apart from the fact they won't explode or catch fire in a short circuit situation, you can get DIN rail mounted fuse holders that have an integrated switch (so you can disconnect the load easily), like this model: www.hager.it/ecatimages/pdf/LS501.jpg
they also say that you should use more poles in series for dc, if you use ac mcb's. i think abb had most of interesting data for that. because people might use them anyway or no. at least there is info now
Thank you for a very descriptive and detailed video on the differences between the types of breakers. It was just what I needed. That said and much as I am convinced, I am not going to replace the AC breakers currently fitted between my solar panels and charge controller as they have worked well for over a year now.
and will continue to, its a scam to make extra money for "specialty " parts by the solar industry. Amps are a measure of heat, and they are the same for both ac and DC. Simple fact. Its Physics. I would like to see an example of "said" arcing. I have never witnessed such a thing in my 35 years of working with current. I mean,, I've seen arc, but its always been tremendous voltage that caused it off main power lines running AC 440, never form a couple Kilowatts of solar dc power at 48 volts.
@@hartreeservicosemanutencao9494 No. The point was to show the difference between AC and DC arcs and manufacturers take these into account while designing DC breakers. Moreover, the voltage at the solar panel side (before solar controller) is higher than 12/48 V. For example a 24-volt solar panel has about 45 V open-circuit voltage.
Adam , you could use an automotive load tester to test breakers & fuses . Two main types , resistance wire [ I would not use this one , less control ] and carbon pile - this one you can dial in the load amount . John
The permanent magnet is why the Midnight Solar is listed as polarised and has the positive signs printed. The South African breaker can handle AC and DC because it doesn't have the magnet. The permanent magnet seemed like a good idea at the time but is prone to installation error and is the reason they catch fire (and why they are no longer recommended). I have looked up the Clipsal AC MCB (4CB150/6) specifications and found them rated for up to 48 VDC, for how much longer I don't know. Definitely not usable on PV strings. Merlin Gerin and Clipsal are both Schneider brands. I have just looked up the details for the Merlin Gerin C60H breakers. The standard AC breakers do not list a DC usage, they are a high rated (10KA) AC breaker. There is a C60H DC range rated at 250 VDC per series pole which means for PV strings buy the appropriate 2, 3, 4 pole breaker dependent on the string open circuit voltage at its coldest temperature and connect the correct number of poles in series. The diagram show connection details. The two items that aren't Merlin Gerin are called magnetic circuit breakers and the cylinder inside the coil which contains oil is called the dash pot. Magnetic breakers tend to be over sensitive to inrush current. Your attempt to explain more positive in a circuit is a good idea but needs editing for accuracy.
The use of circuit breakers in alternating current (AC) and direct current (DC) circuits has some differences, and typically requires specialized designs to cater to specific power types. In AC circuits, the design of circuit breakers is generally standardized and can be widely applied across different power systems. They have the ability to adapt to a wide range of voltages and frequencies, allowing them to function properly under varying AC power conditions. However, in DC circuits, the design of circuit breakers is more specialized. The characteristic of DC circuits is that the current does not undergo periodic variations. Therefore, in order to interrupt the circuit, circuit breakers in DC circuits cannot rely on the natural zero-crossing of AC current. DC circuit breakers need to be specifically designed to handle the requirements of interrupting DC current. DC circuit breakers typically have a more robust structure and special interruption mechanisms to ensure reliable current interruption in DC circuits. They require larger contact gaps and powerful interruption mechanisms to accommodate the continuous DC current. Therefore, to ensure safety and proper circuit protection, it is important to use circuit breakers that are suitable for the specific power type (AC or DC). Using the wrong type of circuit breaker may result in failure to properly interrupt the circuit or damage to the circuit breaker itself. In summary, the use of circuit breakers differs between AC and DC circuits and typically requires specialized designs to adapt to the specific power type, ensuring the safety and reliable operation of the circuit.
The AC breaker is thermally actuated, the other two are magnetically actuated. The advantage of magnetic breakers is they have lower series resistance. Thermal breakers depend on heat to trip, and therefore need series electrical resistance to generate that heat. Both thermal breakers and fuses consume some power from the system because of their dependence on thermal operation. The magnetic arc interrupter on DC breakers is POLARIZED. It is critical to safely interrupting the arc that the polarity not be reversed, which is why they are labelled with polarity markings. Otherwise, the arc may be sustained and cause catastrophic failure (fire). This problem makes those breakers unsuitable in applications where current could be traveling in either direction, such as at a battery terminal where either charging or discharging current is present.
The reason for that sticker, is because Midnite Solar has taken that particular circuit breaker from the South African company CBI, and they have had them "certified" to 150VDC. CBI has a new breaker currently being certified at 300 volts, so the 150VDC breakers from Midnite may soon no longer be available.
Hello Adam! First, thank you so for your very informative videos. Just FYI, I have installed an inline 30A fuse/breaker(just like your 80A) from my 400W panel array to my charge controller. I can assure you it works nicely, as it opens the circuit at 32A coming down from the panels. Actually I'm in the process of connecting the panels in series to increase voltage and decrease current and replace my PWM with a EPEVER 40A, for which I appreciate so much you review. Greetings from the Caribbean!
It is NOT a convention for AC breakers to open at zero voltage OR zero current. The reason why AC breakers and switches can operate with relatively simple and conservative means is because of the inherent plasma/arc quenching which occurs at relatively low frequency (60Hz), low voltage and low current. Crossing 0V and 0A 120x per second causes quenching/extinguishing of plasma repeatedly, which minimizes the heat and conductivity of the gas/plasma and prevents a self-sustaining continuity/conductivity across the gas/plasma. DC, on the other hand does not self-quench, and requires either a much faster movement and larger gap during opening, or it requires a sufficient 'opposing' magnetic field (per the right hand rule), which deflects and 'spreads' the electron flow, which effectively cools/dilutes the plasma and also increases the linear distance/gap the charge must flow. The opposite magnetic polarity would pinch/squeeze the charge together, sustaining the plasma/arc. It's surprisingly complex for a switch, but basically, in order to sustain a plasma, you either want RF power or DC... low frequency AC does not inherently support plasma. Think welders... (as mentioned in the video).
wow,, I have tested my AC breakers on my solar system and they worked flawlessly. Never thought to rip them open and look for differences though. You rock. Still though, the only thing I can think of that could ark that way is lightning strike. And I don't think the magnet will save anything. ;) Like high voltage DC is much more likely to arc than any 12 volt system could ever dream of arcing.
So I came here because of that chinese breaker you show in the beginning. I have the 200A version and found out today that it trips at 150A and gets quite hot under continuous 145A load, to the point that it will trip sooner and sooner down to 100A. So your 80A version is probably good for 40A. It sucks to figure out that nobody has actually used them for their rated current (like you only putting 30A through yours), because I need to put 165A continuously through it and it therefore now is useless for me. If everybody would use them for what they're rated they couldn't sell them like that.
Great video ,the points on most potential still confuses many of my electrically minded friends , argument being if a charger outputs say 60 amps going to a leisure battery they say that is a lot of potential so why wire the positive on the polarity sensitive breaker to the battery if the charging current is flowing from a charger ?
Yeah sorry. I set them uploading last night and must have set part 2 to public by mistake. Part 1 is now live... th-cam.com/video/GyzrxAwxtgA/w-d-xo.html
I have heard bad things about the DC breakers. I have put off buying one because of that. and the good ones. are not cheap. I need 200 - 250 amps. along with a couple 15 or 20amp . and maybe a 60-80 amp. Or multiple 15-20 amp. for each string of solar panels. I don't plan on having more than 250amps of solar power. haha. it would be nice!!! especially if I had the batteries to charge with it! that would be at least 2500 ah. I hope to eventually have 4-5000 ah. in battery. and enough solar to power half my inverter. and still charge about 1000 ah batt bank. in 4-5 hours from 40% discharge. about 5k to 6kw in solar. I hope to have it in a year or so. if all works out. great video
Using an AC circuit breaker in a DC circuit can result in the following situations: Inability to properly interrupt the circuit: AC circuit breakers are designed to work with the characteristics of AC current, such as naturally interrupting the current when it passes through zero. However, in a DC circuit, AC circuit breakers cannot rely on this mechanism for interruption. As a result, the circuit breaker may fail to properly interrupt the circuit and cannot cut off the current. Potential damage to the circuit breaker: The continuous nature and specific characteristics (such as arcing) of DC current can have adverse effects on AC circuit breakers. Interrupting DC current requires larger contact gaps and more powerful interruption mechanisms, which AC circuit breakers may not be able to accommodate. Using an AC circuit breaker in a DC circuit can lead to damage or failure of the circuit breaker. Increased safety risks: Using an inappropriate circuit breaker can prevent the circuit from being properly disconnected, which can result in circuit overloads, fires, or other safety risks. In a DC circuit, proper design and adaptation of the circuit breaker are crucial due to the specific characteristics of DC current. Therefore, to ensure the safe operation of the circuit, it is important to choose the appropriate circuit breaker that meets the specific requirements of the circuit. In a DC circuit, specialized DC circuit breakers should be used to ensure reliable circuit interruption and proper protective functions.
These look like very good circuit breaker. Being a automotive mechanic I was wondering if the small resetting circuit breakers used in vehicles would work. They come in two types. Mechanical bi-Metallic and electronic. The mechanical type will allow for a short over load before tripping. One disadvantage is that when a wire is shorted there will be a spark before the breaker cuts off the current. The electronic circuit breaker is also know as a sparkless breaker in that no spark is produced when a wire is shorted. I am thinking there might not be an ability to pass a short over load current. The mechanical breaker resets as soon as it cools down while the electronic breaker resets as soon as the over flow current path stops. Have any idea if these automotive auto resetting breakers would be a good fit for solar protection? They don't seem have any any fancy arc extinguishing ablities but would that be needed if inductance or capacitance was not in the circuit?
Hi there! Thank you for the video. One quick question, in a two panels system with a microinverter (plug and play), where should I install my circuit breakers, in the DC or AC side?
Adam you didn't metion the types. type B should be used for DC currents, defined in the BS7671 standard, you can get away with a type A but the type B is cheaper and does a better job with DC currents.
I have a sxs and 1 night we rode went to sleep and woke up to my sxs almost on fire something shorted out so now I take battery cable off everytime it's going to be setting without me right there by it anyway I want to put a breaker on it NOT FOR PROTECTION but just to kill all power so I don't have to keep putting cables on and off a ac breaker would fit best in space I have what do yall recommend I use thanks in advance....
i read that there is a physical difference in distance of the contacts for dc breakers to prevent arcing after it breaks. i didnt see that you measured this.
Adam at 3:33 in your video you have all 3 breakers standing in a metal strip. Is this strip available and can you tell me where to get it. Following your video I have order 2 10A DC circuit breakers from Amazon but need a method of mounting them. Thanks for any help. Regards David
Jeff Venqueleir din rail www.amazon.co.uk/gp/product/B06XZYSBR1/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1 Breakers www.amazon.co.uk/gp/product/B06W55G4KR/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1 Hope this helps. The breakers took over a month to arrive in the UK. Best Regards David
Hi, may you please explain the part about wiring the DC MCB. You say if you are connecting the DC MCB between the Charge Controller and battery bank the +ve should be on the battery side and the other end of the MCB connected to the charge controller because the battery sits at a higher potential, what about when the charge controller is charging the batteries? Isn't the charge controller sitting at a higher potential when it is charging the batteries?
The other issue to consider and had confused me on MCB selection is that if you have an inverter that also charges the battery/battery bank, the MCB has to be able to handle bi- directional current flow.
what about : Aramox 5 A / 8 A / 10 A / 15 A / 18 A / 20 A / 30 A Thermal Switch Reset, Current Overload Protection Device Circuit Breaker Manual Reset Circuit Breaker Overcurrent Protector(18A)
oh man, i can find circuit breakers throughout electric shops but they never say DC breaker. sellers are also ignorant. any clue on how to spot a dc breaker from the outside?
+TSIRHC SEVAS it is usually stated on the side. It should show current limits at AC and/or DC. On the front of the older AC/DC breaker I looked at it had the DC symbol of a horizontal line with three smaller lines underneath. However the best tip I can give is finding a brand and model and searching for it's data sheet.
+Rod Kirt As I think I mentioned in the video it was the smallest I could find at the time. The charge controller has its own protection - internal fuses. There was also an external fuse box attached to the charge controller circuits (see my video on fuses). This was the last protection device before the battery (or the first depending on how you look at it I guess). So it also had my inverter connected and a couple of other circuits too heavy duty for the load output of my charge controller. Essentially it was just being used as a switch as everything else was fused - either way it's gone now (it's in bits) and the whole system is protected by either 30amp or 15 amp DC breakers. Thanks for the comment.
The AC breaker are known as MCB (IEC 60898 / IEC 60947) using Thermal Magnetic technology While the DC breaker are known as CBE (IEC 60934) using hydraulic Magnetic technology All IEC standard mention can be tested to either AC or DC , also either one technology can be build for AC or DC . What's important is to use DC breaker for DC application , especially the higher voltage is . because the arc chamber and the tripping mechanism (Thermal , Magnetic or hydraulic Magnetic ) are tune to the require tripping sequence.
Question: Is the magnetic block (shown in the lower left) the alternative for the bi-metal strip? As it heats, does it lose enough magnetism to release the armature?
+Livin In A Box Fuse as close to the source of energy as possible. So right next to the battery for example. Then you want to use suitable cable to carry the maximum load used by the device, and fuse at the same level.
I used a ac breaker on my solar system about 20 amp pull at 37v with a 30 amp breaker I used it as a switch and when I turned it off I heard a weird noise like a hiss like no more tha. 30 seconds it cought fire I freaked out
The arc only really becomes an issue with high voltage DC. Basically anything above 30 volts starts to become an issue. I wouldn't use any of those breakers on seriously high voltage DC - say 200 volts plus from a low impedance source.
Thanks Xan. I agree. I think I mentioned in the video the AC/DC breaker was rated for 80 volts and the DC midnite one 150 volts DC. Far above what I need in my 12 volt system. Although I've two sets of panels running at 35-42 volts now.
Even at 150 volts, it could be dicey. A simple way to improve the safety of any breaker on DC is to wire a capacitor across the breaker. That way when the contacts open for a brief time the cap will present a lower impedance & divert the current that would otherwise form the arc. In fact I do this on relays too where there are high currents involved. It prevents a lot of contact burn. Naturally, this can't be done on AC circuits as the capacitor would continue to pass (albeit a lesser) current once the contacts open.
Solenoid=magnetic breaker. Bimetal strip=thermal breaker. Combo is new to me, but thermal breakers will wear out before magnetic ones do, I'm told. Then there's UL or CE or other certifications, that may also account for differences.
@@AdamWelchUK I kinda get what you are trying to say, but even in larger systems, only a switch is used. Fuses are used so that amperages don't runaway and get that big that they cause dahe/fires etc. Solar output amperage can never exceed the Isc short-circuit current specified by the panel.
the car fuse, theres cheap fakes that dont blow.., they glow red and set your car fuse box on fire! guess how i know....poundsops and ebay full of them
advice on breaker..s set up 200w panel to 30a SCC 30a SCC to 100ah battery 100ah battery to 1000w snadi inverter.. pls give me an ideal amps of dc breaker in each connection above.. thx
Question about Polarity: I understood, that the Solarpannel (or Battery) will connected downsite the Breaker and the load upsite. That sounds, that a unit, that should be protected must always connected upsite. This was also my Idea i.e. overcurrent by lightning flash. But what happend, when the danger doesn't come from the Solarpannel but in a bad situation from the Converter, connected with the 220V Power? Is in this case the Solarpannel protected (reverse) by the breaker?
If I understand your question correctly - will the breaker protect equipment in the event of an inverter reverse feeding high ac voltage towards your battery, charge controller and panels? Well as I mentioned in both my breaker and fuse videos, they protect the wiring not the devices themselves. They are also triggered by current, not voltage. In addition to that the design of an inverter shouldn't allow this to happen - there should be a transformer which should isolate the two sides. Now my understanding is that in an over current situation the solonoid will move the correct way despite its polarity - but I haven't tested this, and perhaps I should.
R.E... your 80 amp ebay breaker.. bought a 40 amp one and it started to smoke and has self destroyed inside, the switch no longer works...these are dangerous..
The car audio fuse type breaker? Yeah they aren’t any good really. I took it apart and found it was simply relying on the contact getting warm and separating. I wouldn’t use one any more.
help i have 24 vdc 109 amp hour battery ,into my inverter/charger. the charger is 80 amp and the inverter is about 2000w and has a 25 amp /32 vdc fuse on the inverter side of the unit and a breaker button for the ac charger side of the unit.. what size breaker /switch can i buy . i want to easily disconnect the batteries when not being used because so it will not drain the batteries.
I tig weld, It is with a arc that we melt metal off varying thickness DC switchs of high voltage should not be purchased cheaply You will regret it !!!!
Wow! Serious safety concern. An 80 amp breaker protects an 80 amp circuit. EVERYTHING on the protected side of the circuit would need to be 80 amps (the gauge of your wire, the components). The breaker is supposed to pop when the load exceeds 80 amps. If you put 40 amp wire in your circuit and you get a 70 amp short (lets say you, for some reason, pull 70 amps across it), the wire will melt and burn and your 80 amp breaker will not trip. You can use larger wires, but your circuit breaker MUST be no greater than your lowest part (wire or component). Do NOT do what Adam did. You MUST understand this when working with AC or DC!!! Not understanding this may lead to burning your house down.
its garbage and un-necessary, household breakers work the same. Dc amps are the same as ac amps,, its a scam to believe there is any difference, there is NOT. Its a heat rating, and both AC and DC amps are the same. In other words, if you have so much dc voltage to arc, no breaker can stop it, it will arc elsewhere. Like in your combiner boxes, or even charge controller hookups, etc. etc. The arc argument doesn't cover all the potential points of 'arcing" and is quite dramatic. If you develop an arc, no breaker will save your gear on the arc side anyhow, point is mute.
Super tear down. there is another very important difference. I was told by an old fellow of a well known German relay manufacturer: Its the chemistry of the contacts. While AC contact do not have this arc so much, DC contacts have to withstand a longer duration arc, so the contacts of an AC would not last and even worse they could weld together if switching a high load, where they are supposed to separate. So never do use AC breakers for DC, otherwise they could catch fire!
Nice to see them open, i learned about that only a year ago or so;
I could not find DC ones so been using 2 AC breakers,25 Amp each, for a year now on my 60 VDC solar system, up to 32 Amps; i switch them off manually, only, sometimes several times a day ; it's impossible for the current to go over 32 amps, that is the MAX, so it's not expected that they trip on their own, ever, that is not why they are there; they are there because i need to manually disconect them ( solar panels from the MPPT/batteries ) when i need to adjust the MPPT voltages; this seldom happens;
i expected them to not last, but they still work perfectly; cost me 2 or 3 euros each;
i use 2 of them, 25A each, in parallel; amazingly they never burned and still worl fine;
they are in a place that if they start smoking, or on fire, it does not matter, nothing to burn nearby; i would not do it, otherwise.
Great info! Safety, safety, safety. People need to understand this!
You can use AC breakers perfectly safely on DC, but you need to make sure that:
1. The voltage is not exceeding 50V for a 230/400V breaker
2. The breaking capacity (Icu) is at least 4500A (4,5 kA), this means it has a large enough arc extinguishing chamber.
3. If the breaker is *directly* connected to a large battery bank (more than 200 Ah) use a breaker with Icu=6000A (6kA)
4. If the breaker is *directly* connected to a very large battery bank (more than 500 Ah) use a breaker with Icu=10000A (10kA)
5. If the breaker is connected to another breaker whose Icu is 6000A, you can use an Icu=4500A breaker or a Icu=6000A breaker.
6. If the breaker is connected to another breaker whose Icu is 10000A, you can use an Icu=6000A breaker, an Icu=10000A breaker *but not an Icu=4500A breaker*
This is because larger batteries can supply higher short circuit currents because the internal resistance is lower.
On many US-made DC/AC breakers you can see they are rated for AC at 250V and DC at 50V, which is why this works.
DC arcs are a problem only above 50V. Most welders have an open circuit voltage of 85V, for that reason.
*Also I highly advise AGAINST using breakers with only a magnetic trip (unless you are using them for the intended application that is powering MOTOR ONLY loads), as it is possible that they won't trip on medium overloads that are not enough to trigger the magnetic trip. This can cause damage to wiring.*
+MrOpenGL Some really useful information there thank you. I think I pointed out in the video that there wasn't much to distinguish between the different types on the inside. However I was very conscious that some people may take that to mean ac breaker = dc breaker. I was cautious in my statements quite deliberately.
It's worth noting that I run a twelve volt system - although my panels run at ~35-45v so everything is below the limit you point out.
Again thanks for your input.
Thanks. You did a good video nonetheless!! :-)
I would also point out that the breaking capacity is also relevant for *FUSES*. You have to choose the correct fuse not only based on voltage and nominal current, but also on breaking capacity (that is also rated in kA or A). That's why you have for instance 5x20mm glass fuses that are empty, filled with sand or with a ceramic body that's also filled with sand. The empty one has less breaking capacity than the one filled with sand, which in turn has less breaking capacity than the ceramic one.
Personally I would never use blade type fuses where you would need a breaker of Icu=6000A or more. The gap they open when they fuse is too little and there is no protection against an arc, as the sides are open and the body is made of plastic.
ANL fuses are better, but the best bet if you don't want to use circuit breakers and you would need a breaker with more than 10000A breaking capacity are HRC (usually in 10x38mm format up to 32A).
The advantage of HRC fuses over other types is that apart from the fact they won't explode or catch fire in a short circuit situation, you can get DIN rail mounted fuse holders that have an integrated switch (so you can disconnect the load easily), like this model: www.hager.it/ecatimages/pdf/LS501.jpg
MrOpenGL
Thanks for this input
MrOpenG
MrOpenGL Can I use HRC powder filled fuses (AC) as safety fuses for my solar 12VDC battery bank..
If you read the datasheet, most AC breakers are rated for 48-60V DC nominally systems with 72V DC peak voltage.
they also say that you should use more poles in series for dc, if you use ac mcb's. i think abb had most of interesting data for that. because people might use them anyway or no. at least there is info now
Thank you for a very descriptive and detailed video on the differences between the types of breakers. It was just what I needed.
That said and much as I am convinced, I am not going to replace the AC breakers currently fitted between my solar panels and charge controller as they have worked well for over a year now.
and will continue to, its a scam to make extra money for "specialty " parts by the solar industry. Amps are a measure of heat, and they are the same for both ac and DC. Simple fact. Its Physics. I would like to see an example of "said" arcing. I have never witnessed such a thing in my 35 years of working with current. I mean,, I've seen arc, but its always been tremendous voltage that caused it off main power lines running AC 440, never form a couple Kilowatts of solar dc power at 48 volts.
@@affordablesolarguy Here is your example. th-cam.com/video/Zez2r1RPpWY/w-d-xo.html
@@SouravGhoshIndia 220 dc. Should we compare it to 12/48v, mostly used in solar power?
@@hartreeservicosemanutencao9494 No. The point was to show the difference between AC and DC arcs and manufacturers take these into account while designing DC breakers. Moreover, the voltage at the solar panel side (before solar controller) is higher than 12/48 V. For example a 24-volt solar panel has about 45 V open-circuit voltage.
Thanks Mr Weich, your observations helped me make my mind. Really appreciate it
Adam , you could use an automotive load tester to test breakers & fuses .
Two main types , resistance wire [ I would not use this one , less control ] and carbon pile - this one you can dial in the load amount .
John
That's a good idea - thank you.
Some good stuff on your channel bud though re the Chinese cct bkr don't you think most of the branded expensive ones are also made there?
hi adam did you test the chinese circuit breaker thank you
The permanent magnet is why the Midnight Solar is listed as polarised and has the positive signs printed. The South African breaker can handle AC and DC because it doesn't have the magnet. The permanent magnet seemed like a good idea at the time but is prone to installation error and is the reason they catch fire (and why they are no longer recommended).
I have looked up the Clipsal AC MCB (4CB150/6) specifications and found them rated for up to 48 VDC, for how much longer I don't know. Definitely not usable on PV strings.
Merlin Gerin and Clipsal are both Schneider brands.
I have just looked up the details for the Merlin Gerin C60H breakers. The standard AC breakers do not list a DC usage, they are a high rated (10KA) AC breaker. There is a C60H DC range rated at 250 VDC per series pole which means for PV strings buy the appropriate 2, 3, 4 pole breaker dependent on the string open circuit voltage at its coldest temperature and connect the correct number of poles in series. The diagram show connection details.
The two items that aren't Merlin Gerin are called magnetic circuit breakers and the cylinder inside the coil which contains oil is called the dash pot. Magnetic breakers tend to be over sensitive to inrush current.
Your attempt to explain more positive in a circuit is a good idea but needs editing for accuracy.
The use of circuit breakers in alternating current (AC) and direct current (DC) circuits has some differences, and typically requires specialized designs to cater to specific power types.
In AC circuits, the design of circuit breakers is generally standardized and can be widely applied across different power systems. They have the ability to adapt to a wide range of voltages and frequencies, allowing them to function properly under varying AC power conditions.
However, in DC circuits, the design of circuit breakers is more specialized. The characteristic of DC circuits is that the current does not undergo periodic variations. Therefore, in order to interrupt the circuit, circuit breakers in DC circuits cannot rely on the natural zero-crossing of AC current. DC circuit breakers need to be specifically designed to handle the requirements of interrupting DC current.
DC circuit breakers typically have a more robust structure and special interruption mechanisms to ensure reliable current interruption in DC circuits. They require larger contact gaps and powerful interruption mechanisms to accommodate the continuous DC current.
Therefore, to ensure safety and proper circuit protection, it is important to use circuit breakers that are suitable for the specific power type (AC or DC). Using the wrong type of circuit breaker may result in failure to properly interrupt the circuit or damage to the circuit breaker itself.
In summary, the use of circuit breakers differs between AC and DC circuits and typically requires specialized designs to adapt to the specific power type, ensuring the safety and reliable operation of the circuit.
The AC breaker is thermally actuated, the other two are magnetically actuated. The advantage of magnetic breakers is they have lower series resistance. Thermal breakers depend on heat to trip, and therefore need series electrical resistance to generate that heat. Both thermal breakers and fuses consume some power from the system because of their dependence on thermal operation. The magnetic arc interrupter on DC breakers is POLARIZED. It is critical to safely interrupting the arc that the polarity not be reversed, which is why they are labelled with polarity markings. Otherwise, the arc may be sustained and cause catastrophic failure (fire). This problem makes those breakers unsuitable in applications where current could be traveling in either direction, such as at a battery terminal where either charging or discharging current is present.
The reason for that sticker, is because Midnite Solar has taken that particular circuit breaker from the South African company CBI, and they have had them "certified" to 150VDC. CBI has a new breaker currently being certified at 300 volts, so the 150VDC breakers from Midnite may soon no longer be available.
You should be using a double pole dc breaker breaking the positive and negitive simutaneously as per code on solar panels
Hello Adam! First, thank you so for your very informative videos.
Just FYI, I have installed an inline 30A fuse/breaker(just like your 80A) from my 400W panel array to my charge controller. I can assure you it works nicely, as it opens the circuit at 32A coming down from the panels.
Actually I'm in the process of connecting the panels in series to increase voltage and decrease current and replace my PWM with a EPEVER 40A, for which I appreciate so much you review.
Greetings from the Caribbean!
Matka wie że cpiesz
Piekarz ma sutki
It is NOT a convention for AC breakers to open at zero voltage OR zero current.
The reason why AC breakers and switches can operate with relatively simple and conservative means is because of the inherent plasma/arc quenching which occurs at relatively low frequency (60Hz), low voltage and low current. Crossing 0V and 0A 120x per second causes quenching/extinguishing of plasma repeatedly, which minimizes the heat and conductivity of the gas/plasma and prevents a self-sustaining continuity/conductivity across the gas/plasma.
DC, on the other hand does not self-quench, and requires either a much faster movement and larger gap during opening, or it requires a sufficient 'opposing' magnetic field (per the right hand rule), which deflects and 'spreads' the electron flow, which effectively cools/dilutes the plasma and also increases the linear distance/gap the charge must flow. The opposite magnetic polarity would pinch/squeeze the charge together, sustaining the plasma/arc.
It's surprisingly complex for a switch, but basically, in order to sustain a plasma, you either want RF power or DC... low frequency AC does not inherently support plasma. Think welders... (as mentioned in the video).
wow,, I have tested my AC breakers on my solar system and they worked flawlessly. Never thought to rip them open and look for differences though. You rock. Still though, the only thing I can think of that could ark that way is lightning strike. And I don't think the magnet will save anything. ;) Like high voltage DC is much more likely to arc than any 12 volt system could ever dream of arcing.
Nice video!! I use AC breakers on my solar system and for 6 years without a single problem. Just a tip. Cheaper........
Regards....
So I came here because of that chinese breaker you show in the beginning. I have the 200A version and found out today that it trips at 150A and gets quite hot under continuous 145A load, to the point that it will trip sooner and sooner down to 100A. So your 80A version is probably good for 40A. It sucks to figure out that nobody has actually used them for their rated current (like you only putting 30A through yours), because I need to put 165A continuously through it and it therefore now is useless for me. If everybody would use them for what they're rated they couldn't sell them like that.
Great video ,the points on most potential still confuses many of my electrically minded friends , argument being if a charger outputs say 60 amps going to a leisure battery they say that is a lot of potential so why wire the positive on the polarity sensitive breaker to the battery if the charging current is flowing from a charger ?
Thanks for the tear down Adam. Could you add a link to the Shed Safety Part 1 video - it wasn't obvious which one you meant. Thanks, Paul
+Paul Kennett Sorry, needed to do some more work before I published these. Whoops!
Looking forward to watch part one, keep it on.
Yeah sorry. I set them uploading last night and must have set part 2 to public by mistake. Part 1 is now live... th-cam.com/video/GyzrxAwxtgA/w-d-xo.html
I have heard bad things about the DC breakers. I have put off buying one because of that. and the good ones. are not cheap. I need 200 - 250 amps. along with a couple 15 or 20amp . and maybe a 60-80 amp. Or multiple 15-20 amp. for each string of solar panels. I don't plan on having more than 250amps of solar power. haha. it would be nice!!! especially if I had the batteries to charge with it! that would be at least 2500 ah. I hope to eventually have 4-5000 ah. in battery. and enough solar to power half my inverter. and still charge about 1000 ah batt bank. in 4-5 hours from 40% discharge. about 5k to 6kw in solar. I hope to have it in a year or so. if all works out. great video
Thanks Adam, good video - keep 'em coming!
Was hoping for some tests
I've used AC components on dc out of desperation never had a problem with arking.
I think you forgot to make the part 1 public Adam. Anyway, thanks for the awesome videos!
+Nathan Campos I've messed up - I'll sort this very soon.
Sorry for the delay - my bad. th-cam.com/video/GyzrxAwxtgA/w-d-xo.html
Thanks I was asking the same question myself.
Using an AC circuit breaker in a DC circuit can result in the following situations:
Inability to properly interrupt the circuit: AC circuit breakers are designed to work with the characteristics of AC current, such as naturally interrupting the current when it passes through zero. However, in a DC circuit, AC circuit breakers cannot rely on this mechanism for interruption. As a result, the circuit breaker may fail to properly interrupt the circuit and cannot cut off the current.
Potential damage to the circuit breaker: The continuous nature and specific characteristics (such as arcing) of DC current can have adverse effects on AC circuit breakers. Interrupting DC current requires larger contact gaps and more powerful interruption mechanisms, which AC circuit breakers may not be able to accommodate. Using an AC circuit breaker in a DC circuit can lead to damage or failure of the circuit breaker.
Increased safety risks: Using an inappropriate circuit breaker can prevent the circuit from being properly disconnected, which can result in circuit overloads, fires, or other safety risks. In a DC circuit, proper design and adaptation of the circuit breaker are crucial due to the specific characteristics of DC current.
Therefore, to ensure the safe operation of the circuit, it is important to choose the appropriate circuit breaker that meets the specific requirements of the circuit. In a DC circuit, specialized DC circuit breakers should be used to ensure reliable circuit interruption and proper protective functions.
Thanks and yes you have labeled that point very well. Hope you got the midnite solar breaker bake together and working
Although I have, I think it would be wise to replace it for a factory sealed unit.
These look like very good circuit breaker. Being a automotive mechanic I was wondering if the small resetting circuit breakers used in vehicles would work. They come in two types. Mechanical bi-Metallic and electronic. The mechanical type will allow for a short over load before tripping. One disadvantage is that when a wire is shorted there will be a spark before the breaker cuts off the current. The electronic circuit breaker is also know as a sparkless breaker in that no spark is produced when a wire is shorted. I am thinking there might not be an ability to pass a short over load current. The mechanical breaker resets as soon as it cools down while the electronic breaker resets as soon as the over flow current path stops.
Have any idea if these automotive auto resetting breakers would be a good fit for solar protection? They don't seem have any any fancy arc extinguishing ablities but would that be needed if inductance or capacitance was not in the circuit?
to test that switch you could easily strap a quadcopter to a bench, plug the battery through the trip switch and hit full throttle..
Nice, Thankyou
Thank you for the great explanation
Hi there! Thank you for the video. One quick question, in a two panels system with a microinverter (plug and play), where should I install my circuit breakers, in the DC or AC side?
Adam you didn't metion the types. type B should be used for DC currents, defined in the BS7671 standard, you can get away with a type A but the type B is cheaper and does a better job with DC currents.
I have a sxs and 1 night we rode went to sleep and woke up to my sxs almost on fire something shorted out so now I take battery cable off everytime it's going to be setting without me right there by it anyway I want to put a breaker on it NOT FOR PROTECTION but just to kill all power so I don't have to keep putting cables on and off a ac breaker would fit best in space I have what do yall recommend I use thanks in advance....
Can i use ac/dc breaker in dc circuits.
i read that there is a physical difference in distance of the contacts for dc breakers to prevent arcing after it breaks. i didnt see that you measured this.
Connect power when breaker is open and check what heat ac breaker
Why I use shunt trip breakers...They work...
When does 16A ac breaker brake dc circuit. If i need 15A fuse for solar panel.
clearly explained, subscribed
External Capacitors can also extinguish the DC arc.
sounds implausible
Very good job.
Adam at 3:33 in your video you have all 3 breakers standing in a metal strip. Is this strip available and can you tell me where to get it. Following your video I have order 2 10A DC circuit breakers from Amazon but need a method of mounting them. Thanks for any help. Regards David
Try searching for DIN rail. It’s very cheap and a really useful mounting system.
Thanks Adam I have some on order now Best Regards David
Can You give me the link on amazon where i can find them i nerd also a 10 and 15 amps breaker
Where i can find the link ?
Jeff Venqueleir din rail www.amazon.co.uk/gp/product/B06XZYSBR1/ref=oh_aui_detailpage_o01_s00?ie=UTF8&psc=1
Breakers www.amazon.co.uk/gp/product/B06W55G4KR/ref=oh_aui_detailpage_o02_s00?ie=UTF8&psc=1
Hope this helps. The breakers took over a month to arrive in the UK. Best Regards David
Good video, thanks for the info.
Glad you found it useful!
Hi, may you please explain the part about wiring the DC MCB. You say if you are connecting the DC MCB between the Charge Controller and battery bank the +ve should be on the battery side and the other end of the MCB connected to the charge controller because the battery sits at a higher potential, what about when the charge controller is charging the batteries? Isn't the charge controller sitting at a higher potential when it is charging the batteries?
Yes this is the bit that confuses me really , did you find a solution ?
The other issue to consider and had confused me on MCB selection is that if you have an inverter that also charges the battery/battery bank, the MCB has to be able to handle bi- directional current flow.
what about : Aramox 5 A / 8 A / 10 A / 15 A / 18 A / 20 A / 30 A Thermal Switch Reset, Current Overload Protection Device Circuit Breaker Manual Reset Circuit Breaker Overcurrent Protector(18A)
Thank you.
so how do you know whats correct? Only buy a known branded make from a reputable source 4 x cost ???
Ok its been long enough. What's inside that 80amp (car audio style) breaker. After all it's your pound.
+Glenn Muse There's hidden secret bonus footage... th-cam.com/video/WTA-TQ14XAo/w-d-xo.html
Thumbs up 👍, thank you!
Well Done o’l Boy! 💪
oh man, i can find circuit breakers throughout electric shops but they never say DC breaker. sellers are also ignorant. any clue on how to spot a dc breaker from the outside?
+TSIRHC SEVAS it is usually stated on the side. It should show current limits at AC and/or DC. On the front of the older AC/DC breaker I looked at it had the DC symbol of a horizontal line with three smaller lines underneath. However the best tip I can give is finding a brand and model and searching for it's data sheet.
cheers man
If you have a 80 amp breaker controlling a 20 amp circuit , how could you EVER EXPECT it to be "tripped" ? THINK ABOUT IT!
+Rod Kirt As I think I mentioned in the video it was the smallest I could find at the time. The charge controller has its own protection - internal fuses. There was also an external fuse box attached to the charge controller circuits (see my video on fuses). This was the last protection device before the battery (or the first depending on how you look at it I guess). So it also had my inverter connected and a couple of other circuits too heavy duty for the load output of my charge controller.
Essentially it was just being used as a switch as everything else was fused - either way it's gone now (it's in bits) and the whole system is protected by either 30amp or 15 amp DC breakers. Thanks for the comment.
it would trip the short circuit protection, only the thermal safe would be inoperant
The AC breaker are known as MCB (IEC 60898 / IEC 60947) using Thermal Magnetic technology
While the DC breaker are known as CBE (IEC 60934) using hydraulic Magnetic technology
All IEC standard mention can be tested to either AC or DC , also either one technology can be build for AC or DC .
What's important is to use DC breaker for DC application , especially the higher voltage is . because the arc chamber and the tripping mechanism (Thermal , Magnetic or hydraulic Magnetic ) are tune to the require tripping sequence.
Question: Is the magnetic block (shown in the lower left) the alternative for the bi-metal strip? As it heats, does it lose enough magnetism to release the armature?
How do you know what to fuse and where for the fuse to be ?
+Livin In A Box Fuse as close to the source of energy as possible. So right next to the battery for example. Then you want to use suitable cable to carry the maximum load used by the device, and fuse at the same level.
Please open the cheap ebay one as I suspect they aren't what we think they are!
I did... it’s a bit rough round the edges (both the video and the breaker)! th-cam.com/video/WTA-TQ14XAo/w-d-xo.html
Good
Cheap sound good, but after your house get burn down, it become very expensive. 😳
Good video ty
I used a ac breaker on my solar system about 20 amp pull at 37v with a 30 amp breaker I used it as a switch and when I turned it off I heard a weird noise like a hiss like no more tha. 30 seconds it cought fire I freaked out
Solar penal na sell milega kaha
The arc only really becomes an issue with high voltage DC. Basically anything above 30 volts starts to become an issue. I wouldn't use any of those breakers on seriously high voltage DC - say 200 volts plus from a low impedance source.
Thanks Xan. I agree. I think I mentioned in the video the AC/DC breaker was rated for 80 volts and the DC midnite one 150 volts DC. Far above what I need in my 12 volt system. Although I've two sets of panels running at 35-42 volts now.
Even at 150 volts, it could be dicey. A simple way to improve the safety of any breaker on DC is to wire a capacitor across the breaker. That way when the contacts open for a brief time the cap will present a lower impedance & divert the current that would otherwise form the arc.
In fact I do this on relays too where there are high currents involved. It prevents a lot of contact burn. Naturally, this can't be done on AC circuits as the capacitor would continue to pass (albeit a lesser) current once the contacts open.
That's a really interesting idea. Thanks
@@AdamWelchUK Great Video. Love your work. Do you have anything further to add 5 years on?
Solenoid=magnetic breaker. Bimetal strip=thermal breaker. Combo is new to me, but thermal breakers will wear out before magnetic ones do, I'm told.
Then there's UL or CE or other certifications, that may also account for differences.
why do you need a fuse for your solar output/controller input?
On small arrays you don’t. However on larger arrays they can provide a lot of power and as such can cause a spark or damage equipment if shorted.
@@AdamWelchUK I kinda get what you are trying to say, but even in larger systems, only a switch is used. Fuses are used so that amperages don't runaway and get that big that they cause dahe/fires etc. Solar output amperage can never exceed the Isc short-circuit current specified by the panel.
440Am batt at 12v. What breaker size would I use from batt to inverter?
100Ah DC fuse
I’m going to invent an ac and do a breaker 😅
the car fuse, theres cheap fakes that dont blow.., they glow red and set your car fuse box on fire!
guess how i know....poundsops and ebay full of them
Simpy Perfect!
no smoke?
advice on breaker..s
set up
200w panel to 30a SCC
30a SCC to 100ah battery
100ah battery to 1000w snadi inverter..
pls give me an ideal amps of dc breaker in each connection above.. thx
You need to consider the voltage of your panel and battery. Without that, you can’t calculate the current which you need for your breakers. I=P/V
Thanks for sharing :-)
Question about Polarity:
I understood, that the Solarpannel (or Battery) will connected downsite the Breaker and the load upsite.
That sounds, that a unit, that should be protected must always connected upsite. This was also my Idea i.e. overcurrent by lightning flash.
But what happend, when the danger doesn't come from the Solarpannel but in a bad situation from the Converter, connected with the 220V Power?
Is in this case the Solarpannel protected (reverse) by the breaker?
If I understand your question correctly - will the breaker protect equipment in the event of an inverter reverse feeding high ac voltage towards your battery, charge controller and panels?
Well as I mentioned in both my breaker and fuse videos, they protect the wiring not the devices themselves. They are also triggered by current, not voltage. In addition to that the design of an inverter shouldn't allow this to happen - there should be a transformer which should isolate the two sides.
Now my understanding is that in an over current situation the solonoid will move the correct way despite its polarity - but I haven't tested this, and perhaps I should.
R.E... your 80 amp ebay breaker.. bought a 40 amp one and it started to smoke and has self destroyed inside, the switch no longer works...these are dangerous..
The car audio fuse type breaker? Yeah they aren’t any good really. I took it apart and found it was simply relying on the contact getting warm and separating. I wouldn’t use one any more.
See the DC arc in action with and without the magnet here: th-cam.com/video/WeVHtMMbYvM/w-d-xo.html
Thanks to shell that~~
how much DC breaker ?
Midnight Solar DC breakers are about $13 each. Same price no matter is 15 amp breaker or 30 amp breaker.
the breaker protects the wire, not the device. please avoid advice on this channel.
how about square d qo breakers
i would like to know the answer also
A bit late but.
www.schneider-electric.us/en/faqs/FA125383/
👍
i got 38 amps on amazon for 3.99 plus shipping for 3.50 something like that
help i have 24 vdc 109 amp hour battery ,into my inverter/charger. the charger is 80 amp and the inverter is about 2000w and has a 25 amp /32 vdc fuse on the inverter side of the unit and a breaker button for the ac charger side of the unit.. what size breaker /switch can i buy . i want to easily disconnect the batteries when not being used because so it will not drain the batteries.
If you do bring in 80 amps into your battery from solar then you'll need to look at a breaker that can happily carry that current.
I tig weld,
It is with a arc that we melt metal off varying thickness
DC switchs of high voltage should not be purchased cheaply
You will regret it !!!!
Wow! Serious safety concern. An 80 amp breaker protects an 80 amp circuit. EVERYTHING on the protected side of the circuit would need to be 80 amps (the gauge of your wire, the components). The breaker is supposed to pop when the load exceeds 80 amps. If you put 40 amp wire in your circuit and you get a 70 amp short (lets say you, for some reason, pull 70 amps across it), the wire will melt and burn and your 80 amp breaker will not trip. You can use larger wires, but your circuit breaker MUST be no greater than your lowest part (wire or component). Do NOT do what Adam did. You MUST understand this when working with AC or DC!!! Not understanding this may lead to burning your house down.
its garbage and un-necessary, household breakers work the same. Dc amps are the same as ac amps,, its a scam to believe there is any difference, there is NOT. Its a heat rating, and both AC and DC amps are the same. In other words, if you have so much dc voltage to arc, no breaker can stop it, it will arc elsewhere. Like in your combiner boxes, or even charge controller hookups, etc. etc. The arc argument doesn't cover all the potential points of 'arcing" and is quite dramatic. If you develop an arc, no breaker will save your gear on the arc side anyhow, point is mute.