Just the right video at just the right time! I live in Arizona just west of the Phoenix metro. Out here, one big issue is heating of RV electrical pedestals. Yes, during summer in the desert, an RV pedestal is like an engine compartment. Because a pedestal can reach 160F from sunlight alone, wiring has to be upgraded regarding insulation temperature range and de-rated regarding current. Now, I can just send a link to this video, rather than giving a long-winded explanation.
Good summary and rules of thumb. Recommend every DIY electrician have and use a current copy of RVIA LV, ABYC E-11, and NFPA-70 for all wire sizing. As you described, you must address the debating issues of continuous loads, temperatures, etc. Especially helpful that you mentioned the temperature issue as we seen Van DIYers who under size wiring to roof top ACs, fans, lighting, etc. where the rooftop temperatures are much higher than walls. Thanks for sharing another excellent episode.
In solar / battery systems, for DC, the voltage drop definitely overrides everything else, but another factor is just straight-out thermal cycling of terminals and conductors adding unnecessary heat and stress to equipment, particularly on DC systems where large capacitors are present near the terminal whos lifespans are impacted by heat transmitted via cabling. And in mobile applications you don't really want any of your wiring to actually hit 90C anyway (or even 60C to be honest). You still use 90C+ rated wiring, but shoot for actual temperatures of 60C or lower. The biggest sizing problems occur at lower system voltages. In a 12V system, it doesn't take very much voltage drop before you are quickly exceeding a 10% loss in power transmission. At the same time, the cabling can wind up getting just way too thick (and expensive) to deal with it. People often fudge and allow larger losses and more heat than desired. But at 24V or 48V there is no reason to use anything but the most conservative wire sizes, because so much more power can be transmitted. One isn't forced to go into the AWG 0's and cabling losses due to voltage drop wind up being less than 2%. And similarly for solar panel wiring. In my case, in terms of the amount of continuous current that I want to support without having to deal with large losses or heat, as a rule of thumb I use 2 AWG for 100A (roughly 5000W @ 51.2V), 12 AWG for 10A, 10 AWG for 20A, and 6 AWG for 35A. -Matt
I am a little confused. My RV has #10 stranded wire installed for the pre-installed solar. Victron says I need a 35A fuse for my 100/30 and a 40A for my 150/35. Based on Table 4A, #10 in the worst condition (60* Insulation) will handle 40A just fine. Is this a true statement? The #10 is run up the wall across the scaling and down to the fuses in the frame, then to the battery on the front of the trailer.
What is recommended grounding wire awg size for a solar system? for 200Amp AC ? for 600Amp Rack (6x100Amp) DC ? for ground wire from grounding rack 300 feet from inverters, to run ground wire from rack to inverters ?
If you've ordered your parts/components/wires/etc from our store shop.exploirst.life, that's a free service we offer. Just submit a support ticket at shop.explorist.life/support
Hi...I am paralleling two 12 volt Victron Multiplus 2 inverters...they are the 120 X 2 50 amp models...I have a fairly large lithium battery bank...2400AHs....my question is, How big do the DC cables need to be coming from the batteries?...I have 4/0 gauge now but they get pretty warm when I'm running 2 AC units...should I double up the positive and negative battery cables going from the batteries to the inverters?....there doesn't seem to be much info on youtube concerning this...and reading the victron manual isn't helping much....thanx in advance...hope you can help.
Unfortunately; a dual Mutliplus 3k system on a 12V battery bank is not reasonable to wire up and you should instead go with a 24V system. Hopefully you haven't already purchased the inverters. 😬 If you have purchased/are purchasing from our store (shop.explorist.life) reach out for some more personalized help: shop.explorist.life/support If you've purchased/are purchasing elsewhere, reach out to your dealer for support. We'd love to have you as a shop.explorist.life customer so we can provide a bit more help in the future and make sure you get the parts you need from the start so we can avoid these problems.
@@EXPLORISTlife Yes...I have already purchased the 2 inverters and hooked them up...they do run the 2 roof air conditioners, but as I said, the wires seems a bit warmer than I would like...would it help to double up on the DC cables?...Going to the inverters?...you say it's not "reasonable" to wire up?...so why then would Victron say they can be run in parallel?
Never mind!...I found the weak link in my 4/0 cables and corrected the issue...the cables now just get barely warm to the touch....the system works flawlessly...don't know why everyone says you can't parallel 12 volt inverters....because you can...and I did!...and now, no need to convert down to 12 volts like you have to do with a 24 volt system.
Glad you got it to work! I never said it COULDN'T work... I said it can't 'reasonably' work. In other words; in order to get a 6kVA 12V system up to ABYC standards, the standards we set here on this channel, or even manufacturers recommendation; you have to use 4/0 wire from Lynx Distributor to each multiplus (this isn't a problem), but then you have to double up that amount of copper from battery bank to lynx distributor where, to stay within standards/regulations, and fusing a switching gets signifantly more costly, complicated, and bulky. This is why you don't see a dual Multiplus 3k 12V system on our store.
You love these sessions hey Nate? and the acute swelling of the brain they cause! I got several different auto cables, only one has the temperature rating printed on it, how can I ascertain temp rating on the others?? The Narva brand auto cable doesn’t have the temp printed on its reels, or is all auto cable a standard 105deg? Happy to understand some electrical fundamentals but definitely won’t be a giru.
Exactly! Story Time: One of our industry friends said that he was working on a piece of equipment (a big transformer, or something industrial like that... I don't remember) that, internally, had a 14AWG wire that had to be capable of flowing something like 100A over 6". Since voltage drop over such a short piece of wire was effectively a non-issue the equipment manufacturer was able to use 14 AWG wire BUT... the wire had insulation on it that had a temperature rating of something crazy like 500C. 😲😲
Thanks for watching, but I don't take video production advice from somebody who's most recent video is some random un-edited shakey assed snowboard video. Perhaps work on your own videos before critiquing mine. Or better yet, just keep that kind of thing to yourself since nobody asked.
Just the right video at just the right time! I live in Arizona just west of the Phoenix metro. Out here, one big issue is heating of RV electrical pedestals. Yes, during summer in the desert, an RV pedestal is like an engine compartment. Because a pedestal can reach 160F from sunlight alone, wiring has to be upgraded regarding insulation temperature range and de-rated regarding current. Now, I can just send a link to this video, rather than giving a long-winded explanation.
That's great insight! A consideration I hadn't thought of but does make sense!
Good summary and rules of thumb. Recommend every DIY electrician have and use a current copy of RVIA LV, ABYC E-11, and NFPA-70 for all wire sizing. As you described, you must address the debating issues of continuous loads, temperatures, etc. Especially helpful that you mentioned the temperature issue as we seen Van DIYers who under size wiring to roof top ACs, fans, lighting, etc. where the rooftop temperatures are much higher than walls. Thanks for sharing another excellent episode.
Great info. Thanks for sharing. Cheers
Excellent information!
Good information
In solar / battery systems, for DC, the voltage drop definitely overrides everything else, but another factor is just straight-out thermal cycling of terminals and conductors adding unnecessary heat and stress to equipment, particularly on DC systems where large capacitors are present near the terminal whos lifespans are impacted by heat transmitted via cabling. And in mobile applications you don't really want any of your wiring to actually hit 90C anyway (or even 60C to be honest). You still use 90C+ rated wiring, but shoot for actual temperatures of 60C or lower.
The biggest sizing problems occur at lower system voltages. In a 12V system, it doesn't take very much voltage drop before you are quickly exceeding a 10% loss in power transmission. At the same time, the cabling can wind up getting just way too thick (and expensive) to deal with it. People often fudge and allow larger losses and more heat than desired.
But at 24V or 48V there is no reason to use anything but the most conservative wire sizes, because so much more power can be transmitted. One isn't forced to go into the AWG 0's and cabling losses due to voltage drop wind up being less than 2%. And similarly for solar panel wiring.
In my case, in terms of the amount of continuous current that I want to support without having to deal with large losses or heat, as a rule of thumb I use 2 AWG for 100A (roughly 5000W @ 51.2V), 12 AWG for 10A, 10 AWG for 20A, and 6 AWG for 35A.
-Matt
Romex must be sized using the 60 degree column in the NEC. Please look at article 334.
I am a little confused. My RV has #10 stranded wire installed for the pre-installed solar. Victron says I need a 35A fuse for my 100/30 and a 40A for my 150/35. Based on Table 4A, #10 in the worst condition (60* Insulation) will handle 40A just fine. Is this a true statement? The #10 is run up the wall across the scaling and down to the fuses in the frame, then to the battery on the front of the trailer.
Hi Nate, what happened to your cable and accessories store?
What do you mean?
What is recommended grounding wire awg size for a solar system?
for 200Amp AC ?
for 600Amp Rack (6x100Amp) DC ?
for ground wire from grounding rack 300 feet from inverters, to run ground wire from rack to inverters ?
Hey, I´m buuilding my van and I want to be sure that everything is ok with my wires. Do you have a service tto check my specific situation? Thanks!
If you've ordered your parts/components/wires/etc from our store shop.exploirst.life, that's a free service we offer. Just submit a support ticket at shop.explorist.life/support
Hi...I am paralleling two 12 volt Victron Multiplus 2 inverters...they are the 120 X 2 50 amp models...I have a fairly large lithium battery bank...2400AHs....my question is, How big do the DC cables need to be coming from the batteries?...I have 4/0 gauge now but they get pretty warm when I'm running 2 AC units...should I double up the positive and negative battery cables going from the batteries to the inverters?....there doesn't seem to be much info on youtube concerning this...and reading the victron manual isn't helping much....thanx in advance...hope you can help.
Unfortunately; a dual Mutliplus 3k system on a 12V battery bank is not reasonable to wire up and you should instead go with a 24V system. Hopefully you haven't already purchased the inverters. 😬
If you have purchased/are purchasing from our store (shop.explorist.life) reach out for some more personalized help: shop.explorist.life/support
If you've purchased/are purchasing elsewhere, reach out to your dealer for support. We'd love to have you as a shop.explorist.life customer so we can provide a bit more help in the future and make sure you get the parts you need from the start so we can avoid these problems.
@@EXPLORISTlife Yes...I have already purchased the 2 inverters and hooked them up...they do run the 2 roof air conditioners, but as I said, the wires seems a bit warmer than I would like...would it help to double up on the DC cables?...Going to the inverters?...you say it's not "reasonable" to wire up?...so why then would Victron say they can be run in parallel?
Never mind!...I found the weak link in my 4/0 cables and corrected the issue...the cables now just get barely warm to the touch....the system works flawlessly...don't know why everyone says you can't parallel 12 volt inverters....because you can...and I did!...and now, no need to convert down to 12 volts like you have to do with a 24 volt system.
Glad you got it to work!
I never said it COULDN'T work... I said it can't 'reasonably' work. In other words; in order to get a 6kVA 12V system up to ABYC standards, the standards we set here on this channel, or even manufacturers recommendation; you have to use 4/0 wire from Lynx Distributor to each multiplus (this isn't a problem), but then you have to double up that amount of copper from battery bank to lynx distributor where, to stay within standards/regulations, and fusing a switching gets signifantly more costly, complicated, and bulky. This is why you don't see a dual Multiplus 3k 12V system on our store.
@@EXPLORISTlife Gottcha....well mine works great!...thanks for the info...
You love these sessions hey Nate? and the acute swelling of the brain they cause! I got several different auto cables, only one has the temperature rating printed on it, how can I ascertain temp rating on the others?? The Narva brand auto cable doesn’t have the temp printed on its reels, or is all auto cable a standard 105deg? Happy to understand some electrical fundamentals but definitely won’t be a giru.
If nothing is stamped on the side, you're in a tough spot and I'd question the quality of the wire.
Where can I find that chart at 2:13 to print it out?
Google search for ABYC and the table name. I pulled that from the ABYC standards, but I have to pay for those, so I can't really link to them.
Or just pause it, screenshot it, and print it. We've got an expensive assed 4k camera and upload in 4k for a reason. 🤣🤣👍
@@EXPLORISTlife Thank you! Got it. Much appreciated.
How many amps can a wire handle? Typically more than the insulation.
Exactly! Story Time: One of our industry friends said that he was working on a piece of equipment (a big transformer, or something industrial like that... I don't remember) that, internally, had a 14AWG wire that had to be capable of flowing something like 100A over 6". Since voltage drop over such a short piece of wire was effectively a non-issue the equipment manufacturer was able to use 14 AWG wire BUT... the wire had insulation on it that had a temperature rating of something crazy like 500C. 😲😲
Good info, but the sound effects turn me off. I didn’t finish the video.
Thanks for watching, but I don't take video production advice from somebody who's most recent video is some random un-edited shakey assed snowboard video. Perhaps work on your own videos before critiquing mine. Or better yet, just keep that kind of thing to yourself since nobody asked.