Am looking for some electrical code help

[dcg9381]

690.31(D)'s paragraph title says "on or in a building" but the text only talks about "in" a building. It would appear to me that the "on" part only refers to roof mount systems. Mine will be a ground mount.

I think it still applies when the conduit transitions to the building. That part is "in a building". As soon as you come up the wall or through the foundation, you need to have metal conduit. You read it the same way I do for ground mount - you can do PVC until you get to that building.

It would not apply if your ground mount array and inverter are all outdoors not inside a structure.

RSD - I thought that I had this one packed away a long time ago. Thought that I had read somewhere that ground mount systems did NOT require RSD. I've read 690.12 and that text is as clear as mud to me. Am I correct in believing for a ground mount array that an RSD is not required?

Looks like it wasn't required -> required in 2020 -> exempted in 2023.

As of 2023 NEC:
"Ground-mounted PV system circuits that enter buildings, of which the sole purpose is to house PV system equipment, shall not be required to comply with 690.12."

That exception didn't exist in 2020 NEC. Here, they wouldn't pass that - they don't honor the newer code.

In any case I plan on including a manual disconnect at the array. And then the SolArk has a PV disconnect switch on it and the PV wire enters the wall less than 3' from the SolArk. So I think I'm covered on the disconnect requirement?

Ask who is doing the inspection. I believe NEC requires the disconnect to be on the "building" (not at the array) or inside at the point of entry. I am NOT CLEAR on this, so you want to comply with who is going to be checking off on the permitting. Here, they want it on the building and require that it's outside. Needs an obvious label. Basically they want to make it super easy for firemen to find.

The rural co-op rep told me that they have their own inspection criteria. He said that if the state passed the installation, that MOST LIKELY they would also pass it. I live in a rural, technically backwards county. I'd classify them as at least 10 years behind other places. The rural co-op does not like residential solar, but need the offsets for the state. They are into commercial solar that they then resell to the consumer. This has been an uphill battle. For the county inspector, I had to show proof that LFP batteries were relatively safe, did not require a vented cabinet and did not require a drain.

Same situation here, except there is no "state inspection". It's the POC inspection only (it's their grid, no state grid). It's worth having a conversation with the inspection (state) over having to re-wire something.

I had thought that I had reduced my list of issues/questions to just figuring out how to interface with the grid: gutter sizes, types of splices or power distribution blocks, wall pass throughs, most efficient way to wire the xfer switch and production meter, conduit fill, EGC, etc. But I think I'm doing a circle back on things I thought I had understood.

Way better to figure it out, draw it out, than have surprises. You're doing just fine. This crap is complicated and it changes.

 

[Hedges]

I'm aware of NEC 2020 690.12 as I read it there are 3 compliant options:

• Install a PV hazard control system listed for the purpose. (I believe this is what I have, an all-in-one RSD)

"all in one RSD"? Isn't that a module per panel?

• Install the PV arrays so that they have no exposed wiring methods or conductive parts and install them more than 8 feet from exposed grounded conductive parts or ground. (this seems really difficult unless your array is "ground mount" - insulated, and at least 8' up)

One forum member put fencing around his array. Not related to RSD, just protecting against access to wires. He used plastic fencing which the inspector didn't like but let slide.

I don't think the paragraph you quoted is for ground mounts, which don't require RSD. I think it is more for solar shingles with wires inside the attic.

I'm good. It's the POC that sets our standards, they're on some old ass version of NEC and frankly they don't even look at the array.

Thank you for your reply. I like staying current.

I was happy to be without RSD or AFCI, ground mount and all PV DC in metal conduit outside. But my new install will be on roof of a house, and I would like to ensure AFCI triggers RSD for best fire protection.

I'm a bit out of date, for instance still think 120% rule applies to PV breaker size but some people say PV generator/inverter amperage. That makes a big difference for battery backup systems with pass-through from grid.

 

[zanydroid]

Limit the controlled conductors inside the array boundary to not more than 80 volts within 30 seconds of rapid shutdown initiation. (this is the 80V limit per limit that you're referencing, it's not one needed PER panel, it's one needed per panels in series producing less than 80V Voc - as you mentioned above)

For some 60 cell panels it is one per panel, and higher cell counts it is always one per panel

For all 54 cell panels the VOC per panel is low enough that you do not need one per panel.

Install the PV arrays so that they have no exposed wiring methods or conductive parts and install them more than 8 feet from exposed grounded conductive parts or ground.

This is the section for solar roof shingle type systems which have wiring inside the modules and no visible frames.

Regular racked panels have tons of exposed TC and PV cable, and the frames are conductive.

 

[zanydroid]

I've been trying to get some help locally and even paid for a consult, but got nothing useful. So coming here to see if I can get some help.

Taking a step back, have you tried to just get full planset drawn for you? I think your system is pretty standard, and this is a standard almost turnkey kind of service companies and people offer.

Having had some planset done, they might sometimes get some arithmetic wrong but overall it’s better than most people can do starting out. I also do not ask them to draw up plans using equipment at the edge of what code & manufacturers would allow.

Is the concern that a plans drawing service that is told to, say, target NEC2020 as adopted by your state, will run into problems with the inspector?

 

[dcg9381]

"all in one RSD"? Isn't that a module per panel?

No, it's more like a combiner and RSD. Only one per array.. At least arrays of moderate size with a single inverter.

Thanks for the other info.. I had not considered shingle type panels - which would be non-conductive.

 

[LBen]

Taking a step back, have you tried to just get full planset drawn for you? I think your system is pretty standard, and this is a standard almost turnkey kind of service companies and people offer.

I've considered this option and am still considering. But - I've already paid $200 for a consult which yielded no useful information. Also, while I'm pretty certain I can get it all to work from an electrical standpoint, the mechanicals are what have me stuck; gutter sizes, wall pass throughs, splices, etc. I don't want to pay for a line drawing that is generic in nature and doesn't address implementation complications. Can you recommend anyone?

 

[Ampster]

Actually microinverters are exempt by how the rules are written.

I would add that micros achieve module level shut down when AC is removed from them. There is still open circuit voltage at each module.

 

[dcg9381]

I've considered this option and am still considering. But - I've already paid $200 for a consult which yielded no useful information. Also, while I'm pretty certain I can get it all to work from an electrical standpoint, the mechanicals are what have me stuck; gutter sizes, wall pass throughs, splices, etc. I don't want to pay for a line drawing that is generic in nature and doesn't address implementation complications. Can you recommend anyone?

You're not required to submit a line drawing to the PoCo?
If you create a general block diagram showing wires and their gauge, we can help you on conduit sizes, etc.
There are probably a bunch of people here that can take a generic drawing and help you with specifics, but starting with block diagrams and as you understand the electrical - adding the wires, it'd be a good place to start.

 

[zanydroid]

I've considered this option and am still considering. But - I've already paid $200 for a consult which yielded no useful information. Also, while I'm pretty certain I can get it all to work from an electrical standpoint, the mechanicals are what have me stuck; gutter sizes, wall pass throughs, splices, etc. I don't want to pay for a line drawing that is generic in nature and doesn't address implementation complications. Can you recommend anyone?

Well what you can expect from the drawings is SLD, overhead plan view, calculations, and spec sheets stapled to the end. And optional engineering stamp certifying that the mounts have been assembled to manufacturer spec.

IOW, basically what the on-site installer would get when they show up at your property, for a turnkey install. Of course that still does leave the tradesman-level knowledge of how to install things, usually plans only call out a few sections of code that are required to be called out, and not every last piece of code and wrench knowledge needed to finish the install. Basically the designer/architect/EE vs workman/technician dichotomy.

Not sure what the most efficient way to get this would be, I would recommend figuring out who on the forum, etc. is most correct on the details and follow or DM them.

 

[zanydroid]

I would add that micros achieve module level shut down when AC is removed from them. There is still open circuit voltage at each module.

Sure. The Voc with microinverters is limited to within that 80V (and other) limits set in the RSD section.

I think technically after you stick a microinverter on it the module is subject to AC solar module rules (maybe, these might exclusively be for modules where the microinverters are embedded inside) and interactive power source rules. Aside -- NEC 2023 brought in a couple other non-DER interactive power sources/smart cabling to the code.

 

[LBen]

One time "Aerospace Engineer" aka "Rocket Scientist" here too.
Normally I'm called EE of some form or another.

I've got this quote thing figured out. First time I tried to do quotes we were having a bad internet day (radio based out here) so was getting a lot of delayed response and inputs just going into never never land.

Where I worked many of us were AeroE, with Math, Physics, EE, CS and other specialties I can no longer recall put into the mix.

 

[LBen]

Ask who is doing the inspection. I believe NEC requires the disconnect to be on the "building" (not at the array) or inside at the point of entry. I am NOT CLEAR on this, so you want to comply with who is going to be checking off on the permitting. Here, they want it on the building and require that it's outside. Needs an obvious label. Basically they want to make it super easy for firemen to find.

Same situation here, except there is no "state inspection". It's the POC inspection only (it's their grid, no state grid). It's worth having a conversation with the inspection (state) over having to re-wire something.

When the state inspector was willing to talk to me, he said that the PV disconnect on the SolArk was sufficient for him to pass as the SolArk was less than 3 ft from where the PV wire entered the building.

Unfortunately for me, I have three organizations inspecting the installation here. The county, state and the co-op. I've dealt with the county guy years ago and I have a pretty good working relationship with him. Part way into the construction of our house, the general quit on us. What a pain to get subs scheduled in to do work and then wife and I did final electric, final plumbing, doors, trim, paint, etc, etc. County guy and I were on a first name basis back then. He is now the head guy in the permit office. I've heard rumors about the state electric guy. He has only been doing it for a couple years. There is rumored some kind of conflict between him and another state inspector that works the area. He says that he only inspects. I've spoken with the co-op solar rep. Remember, this co-op is anti-residential solar. He wants a $500 application fee, a line drawing and an equipment list. I've got all of that but I'm hung up on the nuts and bolts of the installation. I don't want to put $500 out there and end up with a system where I get to the point of "now how the hell am I gonna get this done". Kind of related to permitting - I have only one spot on the property to put the array. It is a rocky hillside. I've got my backhoe out there and it looks like I can build a shelf to put a ballasted ground mount on. Think I can dig a big enough hole to put a ground plate in - no way I can put in a ground rod. Then I have to trench 200' across rocky ground. Can't use a miniX due to the slope. Planning on using a tracked trencher tied off to my side by side UTV (just in case the trencher tries to get away) and I'm not sure I can trench down 20+ inches. This whole installation is a lot of challenges and I'm doubting my sanity in even attempting it.

Way better to figure it out, draw it out, than have surprises. You're doing just fine. This crap is complicated and it changes.

That has been my plan, but I feel that I'm just spinning wheels at this point. I attempted several times to get a consult with a solar install company in Pueblo or Colorado Springs. Willing to pay for their time. They say that they can do it, but they never called back after numerous attempts at me reaching back out to them. I've got a folder about 2" thick of analysis and equipment. Moving electrons from A to B does not cause me issues. I think I can work through the site complications. The grid interconnect looks simple when one does a line drawing. But factor in the limited wall space I have, boring holes through a 13" ICF wall (8 is concrete), not having a good handle on the Code and gray areas of what the inspectors will or will not accept, lack of communication - is raising my blood pressure.

I thank you guys for the help you are providing. Maybe I'll still get through this.

 

[LBen]

You're not required to submit a line drawing to the PoCo?
If you create a general block diagram showing wires and their gauge, we can help you on conduit sizes, etc.
There are probably a bunch of people here that can take a generic drawing and help you with specifics, but starting with block diagrams and as you understand the electrical - adding the wires, it'd be a good place to start.

I'm not familiar with the term PoCo. Yep line drawings have to go to the county, state and co-op. That, site drawings, equipment lists, etc have to be provided with the permit applications. There is about $1200 involved in permit and fee costs. At this point I'm trying to determine if this installation is even feasible before I put out any more money. The drawings I presented in post #2 were what I needed to visualize the wire runs and what is going through the wall via conduit so I could determine conduit size using a conduit fill app. I guess what I came up is non-standard for folks such as yourself. I guess if you can point me to an example format that you and others are familiar with I can redo it in that format. One thing I did in the drawings was to run the service entrance neutral just to the inside gutter and home base the neutral of the SolArk, generator and main panel right there. I saw no reason to run a neutral to the outside gutter. Only wires in the outside gutter are service entrance L1, L2 going to the switch and production meter and then those same wires going back through the wall to the grid connection of the SA. PV and gen wires would also be in the outer gutter. Line drawings I have seen do not show that kind of detail - maybe I just didn't look at the right ones.

 

[LBen]

IOW, basically what the on-site installer would get when they show up at your property, for a turnkey install. Of course that still does leave the tradesman-level knowledge of how to install things, usually plans only call out a few sections of code that are required to be called out, and not every last piece of code and wrench knowledge needed to finish the install. Basically the designer/architect/EE vs workman/technician dichotomy.

Not sure what the most efficient way to get this would be, I would recommend figuring out who on the forum, etc. is most correct on the details and follow or DM them.

Yes, that is where I'm hung up. I was willing to pay to have someone come out, take a look at things and recommend a way to proceed. I have failed at that.

 

[Hedges]

Then I have to trench 200' across rocky ground. Can't use a miniX due to the slope. Planning on using a tracked trencher tied off to my side by side UTV (just in case the trencher tries to get away) and I'm not sure I can trench down 20+ inches.

Overhead wires on poles? PV wire or UF?

Chain link fence or other structure with continuous conduit the wires run through?
Low block wall with conduit surface mounted or inside?

Very shallow trench (6" to 8"), PVC conduit & rebar, filled with concrete and level with the ground? (Is that depth allowed for conduit in concrete?)
Of course, if dirt erodes it will then be sticking up.

 

[Ampster]

Very shallow trench (6" to 8"), PVC conduit & rebar, filled with concrete and level with the ground? (Is that depth allowed for conduit in concrete?)

I have seen some installs where concrete is used to cover and protect conduit which for whatever reason cannot be placed deeper in the ground.

 

[Nobodybusiness]

I've been trying to get some help locally and even paid for a consult, but got nothing useful. So coming here to see if I can get some help.

The site is in Colorado and I'm trying to figure out the best way to do the grid interconnect and be code compliant. I've talked with the local state inspector and he says that he just inspects - very little guidance. This will be a grid tied whole house solar. Was thinking about going completely off-grid, but the rural co-op killed that idea

House was built in 2017 and was approved with a breaker service disconnect at the utility pedestal. The main service panel is inside the garage and the electrical service comes up out of the concrete floor and is behind a 2x4 formed wall cavity. The structural wall is 13" ICF wall (8" concrete and 2.5" foam on both faces). I have a limited amount of wall space on that wall due to windows, the main service panel is between two windows. The 2x4 wall cavity is 36" wide, but has a structural steel support post in the left most space between wall studs, just leaving a single 13" stud bay for any electrical pass throughs.

My current thought is that the SolArk15 will be mounted to the left of the main service panel on the inside wall. I'd have an 8x8x36 wire gutter below to do the wire runs inside. On the outside will be another 8x8x36 gutter for the wire runs outside. Looks like I need 3 pass throughs, a pair of 2.5" EMT and one 1" EMT to pass all of the wires from inside to outside and the other direction. Boring those holes through the ICF wall will be no fun. Outside I think I need a DPDT Xfer switch and I have to have a meter can for the rural co-ops production meter.

The PV is three strings using 10 awg wire plus I need something for an EGC - guessing I have to do 10 awg for that also? Was planning on using PVC conduit to bring PV wire into outside gutter. I currently have an 11kW Generac so those wires have to go through the wall also. The system will also have an LFP battery system positioned in the garage.

I have spent a bunch of time reading through NEC 2020 and have gotten bogged down as to what actually applies and under what conditions. It appears that the local state inspector does not adhere strictly to NEC 2020, which is good (acceptable batteries) and bad (not sure what he will allow). I've also spent hours and hours reading through threads on this forum gaining little bits and pieces of useful info for the system design in general - and I thank everyone for making this resource available.

So I'm hoping someone on this forum can help me out. Is what I've described viable : need more info, better way to do things, can't do it that way - here is how to do it, can't do it at all, or whatever.

Thanks,
Lowell

I can tell you one thing.
If you want to mount The 15k you need a 12’ gutter unless you want to run offset Conduit.

Most inspectors won’t help you because they are not allowed to design just inspect.

 

[dcg9381]

I'm not familiar with the term PoCo.

PoCo = Power Company. In your case, your co-op.

 

[dcg9381]

I attempted several times to get a consult with a solar install company in Pueblo or Colorado Springs. Willing to pay for their time. They say that they can do it, but they never called back after numerous attempts at me reaching back out to them.

You have a resource here that's going to charge you a lot less (nothing). Attempt the drawings yourself, I'm a fan of MS paint.
We will help you.
For me, I can't design the gutter, etc, but I can do a line drawing (I've done many) and I can certainly sanity check your wiring.

Individual "how do I get wire through X" - probably best taken up one post at a time.

 

[Shimmy]

@LBen You are missing some essential information. Specifically:

1. What solar panels are you using?
2. What is your string/ground mount configuration? Series/parallel combination.
3. What is the distance from your array to the house?
4. How many amps do you want to connect from the utility to the SolArk?
5. What is your current peak demand and average daily use?
6. Will you need to re-route any branch circuits?

Don't run the PV cables through the generator enclosure. Period. Don't care why you thought it was a good idea.

Expect to need a disconnect outside for the co-op, knife type typically. Keep it unfused (since it can be backfed in theory). It will just disconnect utility power.

The SolArk has a fairly small wiring compartment. that makes it significantly easier to do your work with the biggest wireway you can get. Code would likely be ok with 8x8, but bigger makes it easier.

The right way to do the holes is to rent a proper core drill from Home Depot for a day and do a couple 4" cores through the wall. This lets you properly seal the openings afterwards and adjust things a little.

As others have suggested, pick a diagram from the SolArk manual that represents what you think hou want to do, and annotate it with what you know.