AHJ told me I need rapid shut down on my 10KW GTpergola array.

[SunEagle]

We''ve never had to install RSD on a ground mount or car port. In many states you can contact the state building official who can guide (overrule) the local AHJ.

Andy

I would hope cooler minds would think it out and make the decision to not require RSD on a ground mount or car port but I have dealt with way too many AHJ's and they usually have the final say.

[khanh dam]

690.12 B2 section 3 says if your PV cables are in conduit under the panels then RSD does not apply if 8 ft above ground. Obviously there would be high voltage lines still coming off the array going into an inverter.

But first sentance of 690.12 says ANY PV circuit in or on a building needs RSD

So what kind of system exactly is 690.12B2:3 referring to??? It's not a ground mount for sure. And if it's a roof mount then why the contradictory code in regards to high voltage lines in conduit. ?

[Ampster]

690.12 B2 section 3 says if your PV cables are in conduit under the panels then RSD does not apply if 8 ft above ground. Obviously there would be high voltage lines still coming off the array going into an inverter.

But first sentance of 690.12 says ANY PV circuit in or on a building needs RSD

So what kind of system exactly is 690.12B2:3 referring to???

As you have mentioned earlier it is subject to interpretation by the local AHJ anyway and that is who you need to get the definitive answer for your installation. However, to answer your question, my system would be an example of how it would be interpreted to apply. My hybrid inverter is located in my attached garage and therefore is "a circuit in or on a building". My panels are on a pergola and the conduit is 8 feet above ground, but the conduit enters the building. Fortunately my inverter was built to comply with that requirement and the manufacturer provided a jumper for that purpose. What I can not answer at this point is how or where that external conduit which carries high voltage DC needs to have RSD protection. My guess is at a point that is 10 feet from the array. I will get that clarified when I apply for the permit.

The above comment is not intended to be a definitive answer or interpretation of the NEC or your local building code. It is just an anonymous poster answering the question of another poster and should not be relied on.

[soby]

I may be late to the game but I figured I'd add my 2 cents. My SolarEdge inverter is in my basement so an externally accessible rapid shutdown switch was required adjacent to the AC disconnect located at my utility meter. It wasn't 100% clear but the inverter had some DIP switches that had to be set correctly and the rapid shutdown switch connected with simple 22GA wire would become operational.

Does your inverter allow for a remote rapid shutdown switch? I would imagine that installing that would be much simpler/cheaper than relocating the inverter.

[khanh dam]

Lol removing 30 panels and installing module level rsd devices on each one then making 30 pv extension cables and reattaching seems to be the real issue

[Ampster]

I may be late to the game but I figured I'd add my 2 cents. My SolarEdge inverter is in my basement so an externally accessible rapid shutdown switch was required adjacent to the AC disconnect located at my utility meter. It wasn't 100% clear but the inverter had some DIP switches that had to be set correctly and the rapid shutdown switch connected with simple 22GA wire would become operational.

Does your inverter allow for a remote rapid shutdown switch? I would imagine that installing that would be much simpler/cheaper than relocating the inverter.

If you are responding to my earlier comment, yes my inverter has a remote RSD capability, but only for the inverter. There are a couple of factors that make the rest of my install different than a SolarEdge system. My system does not have panel level shutdown like SolarEdge deos so that would have to be added if my panels were on a roof, not a pergola or ground mount. Regardless, even if I did not need panel level shutdown I would need to shut down the voltage coming from the panels within a prescribed distance from either the panels or where those conductors enter the building. As mentioned earlier I will get that clarified when this part of the system is reconfigured at a yet to be determined location. It is a moving target.
Speaking of that and looking to the future, the new NEC 2020 has some new standards for batteries. I will start a new post when more details are known about that provision.

[reader2580]

We''ve never had to install RSD on a ground mount or car port. In many states you can contact the state building official who can guide (overrule) the local AHJ.

Going this route will probably ruin your relationship with the inspector forever. The inspector is likely to remember getting a letter from the state every time they inspect your property in the future. The inspector may decide to hold you exactly to the letter of the code rather than letting little things slide. Things like measuring distances and not letting it pass if it is 1/16" too close. I don't think I've never seen an inspector on my half dozen inspections ever use a measuring device and they just eyeball it normally. If the measurement looks right by eye they normally pass it.

The former AHJ for my area wouldn't allow homeowners to do a solar install. I talked to the state and they said he couldn't stop a homeowner from doing solar. I have a friend who is a solar electrician who gave me a real good deal to do all the electrical. I didn't want to get on the inspector's bad side by forcing the issue. The old inspector retired and the new guy is cool and has no issues with a homeowner doing solar. Now that the inspector knows that I know what I am doing he will even answer some code questions for me.

[PVAndy]

Going this route will probably ruin your relationship with the inspector forever. The inspector is likely to remember getting a letter from the state every time they inspect your property in the future. The inspector may decide to hold you exactly to the letter of the code rather than letting little things slide. Things like measuring distances and not letting it pass if it is 1/16" too close. I don't think I've never seen an inspector on my half dozen inspections ever use a measuring device and they just eyeball it normally. If the measurement looks right by eye they normally pass it.

The former AHJ for my area wouldn't allow homeowners to do a solar install. I talked to the state and they said he couldn't stop a homeowner from doing solar. I have a friend who is a solar electrician who gave me a real good deal to do all the electrical. I didn't want to get on the inspector's bad side by forcing the issue. The old inspector retired and the new guy is cool and has no issues with a homeowner doing solar. Now that the inspector knows that I know what I am doing he will even answer some code questions for me.

Actually quite the opposite, we involve the local inspector before calling the state inspector. In most cases they welcome the input. Quite often the state inspector issues a memo to all local inspectors clarifying a point. Personally I also get quite a few calls from inspectors on both our and other installers systems regarding clarification on code issues.

Andy

[reader2580]

Actually quite the opposite, we involve the local inspector before calling the state inspector. In most cases they welcome the input. Quite often the state inspector issues a memo to all local inspectors clarifying a point. Personally I also get quite a few calls from inspectors on both our and other installers systems regarding clarification on code issues.

I, as the homeowner, called the state to clarify if homeowners could install their own solar as the local inspector wasn't allowing it. I ultimately did not report the inspector, but If the local inspector found out who reported them to the state there are plenty of inspectors who would retaliate against the person making the report.

It wasn't ignorance of the rules by the local inspector. He stated he doesn't allow homeowner solar installs because nearly every install failed initial inspection. Reading between the lines I think the real reason was the inspections were taking a lot of extra time and he was losing money on them. Inspectors like to go to the site, make a quick inspection, and sign off It can take time to note all the violations that caused a failure.

[badwithusernames]

As the AHJ has decided that you need the RSS system, aren't there array level shutdown modules? That way you might only need one module per string, instead of per module..
I think 2017 NEC. code states module level, but maybe the AHJ would cut you some slack?
I just finished a 7kw system on my barn, with the inverters in the house basement. I found out about the RSS requirements late in the game and added them, I think it added about a grand in hardware for the transmitter and 22 modules.