Failed Inspection - need some advice and guidance for NEC 690 infractions.

[addision]

1. PV system DC circuits that exceed 30VDC run inside a building shall be contained in a metal raceway. 690.31 D
   
   • OMG! Seriously? I've yet to see an online video where the entirety of the PV DC circuit is encased in metal from the point of entry. Most installations are very similar to mine. I've used liquid-tight for everything and it all needs to be replaced with metal conduit...including my 1-1/2in Sched 80 entry and junction box. I've done my best to figure out an exemption for this, but I can't find one. I have to assume that others here have come across this. I still haven't figured out how / where to transition from PVC to MC. This is going to be quite a cluster indeed.

I live in Southern California and the inspectors here can be a little hard to work with. I didn't want to make all the liquid-tight connections. I went to the local sheet metal fab guy and had this 10x10 raceway made. I had to add some manufacturer stickers for code. But this save a ton of time and money. I had this made for $200 with a cover. Inspector didn't even blink and commented that I had lots of room to work in there. This isn't a picture of the finished product but midway through. My DC enters on the right and feeds to both the inverters. Really simple.

 

[zanydroid]

OMG! Seriously? I've yet to see an online video where the entirety of the PV DC circuit is encased in metal from the point of entry.

And that’s why you don’t learn code from solar videos.

OP can use LFMC or FMC instead of LFNC. Subject to solar specific protection requirements in 690. It won’t look as nice as all that wiring trough with custom knockouts but can be done incrementally with basic tools.

 

[addision]

And that’s why you don’t learn code from solar videos.

OP can use LFMC or FMC instead of LFNC. Subject to solar specific protection requirements in 690. It won’t look as nice as all that wiring trough with custom knockouts but can be done incrementally with basic tools.

I was able to do the knockouts with a drill. I thought about buying a knockout tool, but I didn't want to spend the money. I traced the bottom of the inverters and sub-panels onto cardboard and drilled the holes.

 

[zanydroid]

I was able to do the knockouts with a drill. I thought about buying a knockout tool, but I didn't want to spend the money. I traced the bottom of the inverters and sub-panels onto cardboard and drilled the holes.

I think if you have time, and no wires in there yet, hole drill and then finishing it off after and cleaning out all the crap that pops out, is fine.

My mental model for knockout tool (which I don't have yet), is to do it at high speed in existing installs, and with much less worry about shavings.

 

[Zwy]

I purchased this one at the beginning of my solar journey. https://www.amazon.com/gp/product/B002A94UI2/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1 It works very well. There still is some drilling involved with the pilot hole. Smaller holes can be done with a step drill about as fast.

 

[Hedges]

I bought Greenlee knockout punch (1/2" ... 2") for $200 about 20 years ago. That was even more money then than now (my income was half as much.)

I've used it a number of times since, very happy with it. It is the ratchet handle model.

Harbor Freight has a much cheaper one. Somebody said it got dull fast.

We've used a step bit for a few projects at work, including drilling aluminum boxes. Sometimes snags, spins the workpiece, pulls up and cracks it.

I also use bi-metal hole saws.

I tried a diamond grid saw to cut stucco (with water), but it wore out in two holes.
The carbide toothed one seems to do better.

 

[Zwy]

Diamond blades don't care for steel. If stucco with mesh, I can see why. Diamond will cut steel but it is hard on the blade. I've been running the same 12 inch in my air powered saw for years and it has seen enough use. Never used it without water.

 

[dougbert]

I was able to do the knockouts with a drill. I thought about buying a knockout tool, but I didn't want to spend the money. I traced the bottom of the inverters and sub-panels onto cardboard and drilled the holes.

I got this one and love it

https://www.amazon.com/gp/product/B096TFHN4Q/ref=ppx_yo_dt_b_search_asin_title?ie=UTF8&psc=1

made over a dozen holes now, very clean and no ragged saw marks

 

[Sennen]

I use Temco. They make Hydraulic, too. https://www.amazon.com/dp/B084WWJZH4

 

[robbob2112]

This has nothing to do with a direct lightning strike.
That would be lightning protection. (A completely different system)
This is about the electrical safety grounding system.
This is in regards to the gradient pulse generated by a nearby lightning strike.
I don't want to give that a quick path to my equipment or household appliances.
I want it to dissipate over distance in the earth.

So I think I get it and the video really helps. In my case I am doing lightning strike protection on the mast. That means the mast grounded to the ground rod next to it. BUT, that ground rod should not be connected to the house panel ground in any way. If it is I am asking for trouble.

If i take that and extend the logic for a ground mount array the panels will get a ground conductor to them from the main house panel and conduit. But I would think the racking would act as the axillary ground and cause an issue unless the panels were insulated from the racking.

So how would/should that work?

 

[timselectric]

So I think I get it and the video really helps. In my case I am doing lightning strike protection on the mast. That means the mast grounded to the ground rod next to it. BUT, that ground rod should not be connected to the house panel ground in any way. If it is I am asking for trouble.

If i take that and extend the logic for a ground mount array the panels will get a ground conductor to them from the main house panel and conduit. But I would think the racking would act as the axillary ground and cause an issue unless the panels were insulated from the racking.

So how would/should that work?

Sometimes you are just stuck with what you have.
The EGC is required and necessary for personal safety. The frames and racking must be bonded.
If your racking is in contact with the earth, there's nothing you can do about it, now.
It is what it is.

 

[robbob2112]

Sometimes you are just stuck with what you have.
The EGC is required and necessary for personal safety. The frames and racking must be bonded.
If your racking is in contact with the earth, there's nothing you can do about it, now.
It is what it is.

I am still in learning and early planning stages for solar at this point, but I take your point. But this makes me think I am going to cut the weather station mast to main house ground and recycle the copper.

 

[timselectric]

I am still in learning and early planning stages for solar at this point, but I take your point. But this makes me think I am going to cut the weather station mast to main house ground and recycle the copper.

If there's no power ran to the mast, that's what I would recommend.
But if there is power to the mast, then it should remain for personal safety.

 

[robbob2112]

If there's no power ran to the mast, that's what I would recommend.
But if there is power to the mast, then it should remain for personal safety.

No power. The weather station is solar powered and wireless to the data logger, which reminds me I need to find some sub-c batteries and replace them.

The original station which was destroyed by a direct hit was POE 24vdc with ethernet cable. It did $10k of damage in the house.

Thanks for the info, when I did that 12 years ago I was paranoid because of the recent fun.

 

[Kornbread]

Fingers crossed, I'll be upgrading soon and found this thread very useful.

Question; I live in one of those states that follows no version of the NEC, although, some public facilities are required to follow NEC2005. Wondering what kind of sharknado I'm fixing to get into.

 

[Kornbread]

@meager In post #237, what size is the gutter box?

 

[robbob2112]

Most states in the US have a code cake... meaning local code at the top, county/parish code, and NEC codes. In general if there are no local and county codes they still follow NEC. And, if it is grid tied already and you make changes you have to bring it up to whatever the current spec they are following.

Generally states follow the most recent minus 1 - so currently they would be on NEC2020 and would switch to the NEC2023 once the next one comes out. This gives a predictable guide to follow. Sometimes local jurisdictions will have you follow most current verse 1 old.

So if you don't have anything listed locally I bet if you looked on your state website they will have a blurb that states to follow a specific NEC unless otherwise stated.

 

[meager]

@meager In post #237, what size is the gutter box?

If you are talking about the black EG4 PDP panel under the inverters, which they no longer sell apparently, it is 42in x 12in.

 

[wheisenburg]

PV system DC circuits that exceed 30VDC run inside a building shall be contained in a metal raceway. 690.31 D

• OMG! Seriously? I've yet to see an online video where the entirety of the PV DC circuit is encased in metal from the point of entry. Most installations are very similar to mine. I've used liquid-tight for everything and it all needs to be replaced with metal conduit...including my 1-1/2in Sched 80 entry and junction box. I've done my best to figure out an exemption for this, but I can't find one. I have to assume that others here have come across this. I still haven't figured out how / where to transition from PVC to MC. This is going to be quite a cluster indeed.

All EMT tubing here.