Ah, I understand now. I'm in a rural part of the county and am only under state jurisdiction. I have never been pointed to an additional state or county document that adds requirements above and beyond the NEC.
Am looking for some electrical code help
- Thread starter LBen
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zanydroid
Solar Wizard
Right but there are parts in NEC that say white is only for grounded conductors. It is definitely not allowed for AC individual conductors of that size.
It’s either not repeated in code for DC/PV or there is a conflicting section on DC colors. I don’t have a reference handy.
NEC 690.31(B)(1) Identification:
"... The permanent marking means for nonsolidly grounded positive conductors shall include imprinted plus signs (+) or the word POSITIVE or POS durably marked on insulation of a color other than green, white, or gray. The permanent marking means for nonsolidly grounded negative conductors shall include imprinted negative signs (—) or the word NEGATIVE or NEG durably marked on insulation of a color other than green, white, gray, or red. Only solidly grounded PV system dc circuit conductors shall be marked in accordance with 200.6."
The sol-ark like most modern systems, the PV circuits are nonsolidly grounded.
zanydroid
Solar Wizard
OK great. Somehow Google has a tough find finding this thing compared to the AC rules and handful of AHJ that call this out explicitly in their review instructions…
I did not know about the prohibition on red for the - conductor
Ok, I get it now. Duh. Not living in the electrician's world I have to spend considerable time making sure I understand what is being said. I had to go to a YouTube video in order to get the light turned on in my head (pun intended).
I really have no idea what to expect from this inspector. If he complains, I'll point him to 690.31(B)(2) Exception - "Where the identification of the conductors is evident by spacing or arrangement, further identification shall not be required". I'll point out that the white wire in the PV bundle is just one of the DC string wires. If he still protests, I'll offer the option of labelling the bundle in the gutter. Course the PVC conduit bringing in those conductors will also have the PV Source warnings. I am not going to entertain the idea of pulling a single 10awg 220' just cause he doesn't like the color of the jacket.
I was thinking that the exception I had quoted indicated that further identification of conductors was not required, since they are all pulled together with tie wraps into a bundle. So the fact that I have a red and white wire in my PV bundle of wires violates code?
The bundling of the PV wires handles identification along the run, there is also identification at the ends of circuits, and the polarity of the conductors, that is required, and where the wire colors are involved. Red is an ok wire color to use as long as you use it for a positive conductor, white can't be used for either polarity and use would be a code violation.
I have gone back and reviewed several pages of posts and spent about 6 hours reading and rereading 2023 code and gone down several gopher holes trying to gain information.
I'm going to throw some things out on this thread to see if I understand some things. Or if I don't.
Neutral wire (feeder) - I'm using switch loops running L1/L2 circuits to the xfer switch and the AC disco for the inverter. Neutrals are not required to be run to those devices? I think I can simply branch the neutral at the inside wireway to the breaker panel and to the SolArk?
Inductance/Reactance - I'm running L1/L2 pairs out and back to the xfer switch and to the PM and AC disco for the inverter. With L1 and L2 being 180 out of phase the magnetic fields would cancel. In both runs I have out and back L1/L2 pairs - fields would cancel again. I think there could be a small imbalance that would be negligible?
This inspector requires metal conduit for wall penetrations. ICF wall is a bit over 13", so no inductance/reactance issue there as @pvgirl had noted earlier. Had to buy a 10' stick of the EMT and I hate to throw material away. So there is the one 24.5" EMT which might marginally fall under the exception @pvgirl references. I have a longer EMT run, but since I'm running paired out of phase conductors, I don't think there is an issue there either?
I'm going to throw some things out on this thread to see if I understand some things. Or if I don't.
Neutral wire (feeder) - I'm using switch loops running L1/L2 circuits to the xfer switch and the AC disco for the inverter. Neutrals are not required to be run to those devices? I think I can simply branch the neutral at the inside wireway to the breaker panel and to the SolArk?
Inductance/Reactance - I'm running L1/L2 pairs out and back to the xfer switch and to the PM and AC disco for the inverter. With L1 and L2 being 180 out of phase the magnetic fields would cancel. In both runs I have out and back L1/L2 pairs - fields would cancel again. I think there could be a small imbalance that would be negligible?
This inspector requires metal conduit for wall penetrations. ICF wall is a bit over 13", so no inductance/reactance issue there as @pvgirl had noted earlier. Had to buy a 10' stick of the EMT and I hate to throw material away. So there is the one 24.5" EMT which might marginally fall under the exception @pvgirl references. I have a longer EMT run, but since I'm running paired out of phase conductors, I don't think there is an issue there either?
I guess I'll see if the inspector calls me out on it. Thanks for the clarification. I made a cheat sheet to keep track of the strings, polarities and colors and was going to put labels on the wires at the terminations.
Hedges
I See Electromagnetic Fields!
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L1 and L2 wouldn't cancel to the extent they carry different current, and N is carrying that.
L1 out and L1 back from switch would cancel. For a transfer switch, you'd want all three L1 wires in a single conduit. The three L2 could all be in a different conduit from L1, at least from an electrical (if not code) perspective.
Otherwise, L1/N/L2 all in a given conduit. Source A, Source B, Destination can each be different conduit.
Either way, sum of currents through wires in any given conduit should be zero.
L1 out and L1 back from switch would cancel. For a transfer switch, you'd want all three L1 wires in a single conduit. The three L2 could all be in a different conduit from L1, at least from an electrical (if not code) perspective.
Otherwise, L1/N/L2 all in a given conduit. Source A, Source B, Destination can each be different conduit.
Either way, sum of currents through wires in any given conduit should be zero.
Yeah L1 and L2 out and back from the trough to the switches will cancel out. So you can have all 3 L1 and L2 in a single conduit to the transfer switch. Same for production meter and disconnect 2 L1 and L2 in a single conduit.
Yeah I would wait for the white PV wire to become an issue before changing it out, maybe use some extra stickers on it to make sure it's extra well identified, and the actual wire color is hard to see.
Yeah I would wait for the white PV wire to become an issue before changing it out, maybe use some extra stickers on it to make sure it's extra well identified, and the actual wire color is hard to see.
zanydroid
Solar Wizard
LBen Not sure if you mentioned it in your post, but I mentioned a few posts back that the L1 and L2 returning from the switch into your sub panel also needs to have balanced L1/L2/N through the knockout. I believe there is only one L1/L2 so it needs to be balanced out by going through the same hole in bottom of subpanel as the neutral coming up from the service conductors.
I believe as long as you cancel out the current any remaining incidental radiation (there probably will be some) is not something code cares about
I believe as long as you cancel out the current any remaining incidental radiation (there probably will be some) is not something code cares about
Thinking I may put a long piece of colored heat shrink on it.
zanydroid
Solar Wizard
The game theory is a bit complicated here, it could also attract attention ?
(Colored heat shrink isn’t code compliant for remarking, I don’t think anything is)
Yes, I did see that comment. I interpreted the comment as telling me that the L1/L2 coming into the bottom of the brkr panel (from the xfer switch)must have the neutral going through the same hole. Did I miss something?
Well, dang!!!
If building an airplane like I did back in the 80's was anywhere as difficult as doing a solar installation in the 2020's I would not have built one. Mil-spec wiring that I used is all the same color. Have to have diagrams for all of the pin-outs.
Maintenance test flight went fine yesterday. The previous hydraulic failure was due to an o-ring costing less than $1.
Hedges
I See Electromagnetic Fields!
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You can use any color you want, so long as it is black?
And has phasing tape?
I was wondering if you would make it back.
You said something about testing a repair that needed to work for it to be able to land.
I would have wanted to figure out a way to test that before getting up in the air.
zanydroid
Solar Wizard
The bottleneck here is the conductor size. It’s below the minimum remarking size.
I’m not sure what color people are using for their DC runs, are there 6-8 THHN colors broadly available for #10?
After the repair, the plane was on jacks with the gear up for 2+ hours as a ground test. Gear pump did not cycle when I put power back on - so no leak down. For when the gear is down, there is a pressure gauge that is used to monitor the pressure.
A place called Wire and Cable Your Way sells THHN-2 and XHHW-2 in 9 solid colors. The THHN-2 has additional colors with stripes.
I bought 250' spools of 7 different colors. Wish I would have known about the white thing - there were two other colors I could have chosen. I just went down their pull-down menu color list in order as I loaded up the cart.
