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-   -   Are lug's code compliant on this DIY 175A breaker panel? Needed for 10KW PV system (http://www.diychatroom.com/f18/lugs-code-compliant-diy-175a-breaker-panel-needed-10kw-pv-system-156170/)

superduper 09-08-2012 07:29 AM

Are lug's code compliant on this DIY 175A breaker panel? Needed for 10KW PV system
 
I am getting a 10KW PV (solar photo voltaic) system installed for a relative.
They have a 200AMP load center.
Per NEC code it needs to be downsized to 175A main breaker.

Unfortunately, she has a Siemens PL series 200A load center and Siemens does NOT make a 175A Main Breaker Kit. So instead of just swaping out the main breaker.... we need to do the following:

1. Take out exsisting Siemens 200A Breaker and replace it with two main lugs.
2. Install a new panel with a 175a main Breaker in it
; which feeds the exsisting Siemens panel.

I've gone to a few electrical supply places and NONE of them have heard of a 175 main breaker kit. I finally just ordered a GE one online. It was not easy to find, but I'm resourceful.

Next hurdle was finding an Enclosure/panel, Only ones I could find were full sized 200AMP whole house load centers. It is impractical to put another full size panel in the garage

So I took a smallish 125A breaker box and gutted it.
Put 1/4" thick piece of plastic on the bottom and then bolted the 175A breaker on top
Put Three Main lugs into the panel. One for ground, black and Red.
There was no real way to attach them so I took a 1/4-20 bolt and bolted them on.

Will this pass code? Would you make any changes?
See photo below
http://s9.postimage.org/gxfzxwy19/electrical_panel.jpg
The top wires lead to the meter
the bottom wires would feed the exsisting 200a panel.

http://s9.postimage.org/gxfzxwy19/electrical_panel.jpg

stickboy1375 09-08-2012 09:02 AM

Quote:

Originally Posted by superduper (Post 1005410)
I am getting a 10KW PV (solar photo voltaic) system installed for a relative.
They have a 200AMP load center.
Per NEC code it needs to be downsized to 175A main breaker.

Unfortunately, she has a Siemens PL series 200A load center and Siemens does NOT make a 175A Main Breaker Kit. So instead of just swaping out the main breaker.... we need to do the following:

1. Take out exsisting Siemens 200A Breaker and replace it with two main lugs.
2. Install a new panel with a 175a main Breaker in it
; which feeds the exsisting Siemens panel.

I've gone to a few electrical supply places and NONE of them have heard of a 175 main breaker kit. I finally just ordered a GE one online. It was not easy to find, but I'm resourceful.

Next hurdle was finding an Enclosure/panel, Only ones I could find were full sized 200AMP whole house load centers. It is impractical to put another full size panel in the garage

So I took a smallish 125A breaker box and gutted it.
Put 1/4" thick piece of plastic on the bottom and then bolted the 175A breaker on top
Put Three Main lugs into the panel. One for ground, black and Red.
There was no real way to attach them so I took a 1/4-20 bolt and bolted them on.

Will this pass code? Would you make any changes?
See photo below
http://s9.postimage.org/gxfzxwy19/electrical_panel.jpg
The top wires lead to the meter
the bottom wires would feed the exsisting 200a panel.

http://s9.postimage.org/gxfzxwy19/electrical_panel.jpg

I think you are going about this all wrong... I personally have never done a PV install, so im not up to date in all the code requirements. But i think you are barking up the wrong tree with what you propose.

kbsparky 09-08-2012 09:36 AM

Quote:

Originally Posted by superduper (Post 1005410)
I am getting a 10KW PV (solar photo voltaic) system installed for a relative.
They have a 200AMP load center.
Per NEC code it needs to be downsized to 175A main breaker....

Who says the main breaker has to be downsized? What section of the Code are you using here?

Gac66610 09-08-2012 09:38 AM

I'm with Stick, I also have never done a PV system, what code article are you referring to, that requires the service to drop to 175a?

What's the load calculation of the home? Will 175a provide enough for the home?
And if all is fine why not drop it to 150a, those are easier to find, and they're UL listed

stickboy1375 09-08-2012 09:43 AM

Here is a link to article 690 of the nec, might want to read through this...

http://ecmweb.com/code-basics/solar-...systems-part-1

http://ecmweb.com/code-basics/solar-...systems-part-2

http://ecmweb.com/nec/evolution-sola...oltaic-systems

stickboy1375 09-08-2012 09:50 AM

Quote:

Originally Posted by kbsparky (Post 1005439)
Who says the main breaker has to be downsized? What section of the Code are you using here?

I believe this is why.....

690.64(B)(2)
Quote:

Whether one chooses a load side or supply side connection is often governed by the size of the PV system. If the main circuit breaker plus the PV system circuit breaker(s) are more than 120% of the bus (and conductor) rating, then a service upgrade or supply side connection would typically be required.

For example, let's say a certain house has a typical all-in-one 200A service, and the owner wishes to install a 10kW PV system. The 10kW system would typically be composed of two 5kW systems that have a 21A output, requiring two 30A circuit breakers. So (200A + 30A + 30A) 120% = 217A (minimum bus size). Therefore, the service would have to be upgraded, or a supply side connection would have to be made.

stickboy1375 09-08-2012 09:53 AM

Like I said, PV systems are a little out of my comfort zone, so hopefully you can find some help with this project... Also, as a side note, I would check to see if you are even qualified to do this project at someone else's house. Normally, this is not allowed, family or not...

stickboy1375 09-08-2012 10:03 AM

Quote:

Originally Posted by superduper (Post 1005410)
Next hurdle was finding an Enclosure/panel, Only ones I could find were full sized 200AMP whole house load centers. It is impractical to put another full size panel in the garage

So I took a smallish 125A breaker box and gutted it.
Put 1/4" thick piece of plastic on the bottom and then bolted the 175A breaker on top
Put Three Main lugs into the panel. One for ground, black and Red.
There was no real way to attach them so I took a 1/4-20 bolt and bolted them on.

Will this pass code? Would you make any changes?
See photo below
http://s9.postimage.org/gxfzxwy19/electrical_panel.jpg
The top wires lead to the meter
the bottom wires would feed the exsisting 200a panel.

http://s9.postimage.org/gxfzxwy19/electrical_panel.jpg

There is no way this would pass code, you can't just build your own equipment like that. That disconnect would have to be rated Suitable for Service Equipment also....

Some things are not DIY.... this is one of them. Also, all the grounds and neutrals now need to be separated in the panel, the GEC's need to be moved into the new disconnect. With out a proper load calculation, you might have other issues by lowering the service to 175A.... I don't know what else to say.

kbsparky 09-08-2012 10:12 AM

There is NO 690.64(B)(2) in my Code book.

However, why not connect the inverter output ahead of the service disconnect, as permitted in 230.82(6)? That would solve the bus-bar rating problem here ...

stickboy1375 09-08-2012 10:15 AM

Quote:

Originally Posted by kbsparky (Post 1005453)
There is NO 690.64(B)(2) in my Code book.

Im on 2005, and I know article 690 has changed in the past few years.

Quote:

Originally Posted by kbsparky (Post 1005453)
However, why not connect the inverter output ahead of the service disconnect, as permitted in 230.82(6)? That would solve the bus-bar rating problem here ...

yes it would...

superduper 09-08-2012 10:47 AM

thank you.
 
"What's the load calculation of the home? Will 175a provide enough for the home? And if all is fine why not drop it to 150a, those are easier to find, and they're UL listed"

First I'd like to thank all the quick replies.

Yes a load calculation was done and 175a is fine, but 150 is too small, hence the decision to use 175A breaker.

An extra lug could be bolted to the panel for the grounding electrode, however.......

If this is not code compliant than we will simply replace the entire Siemens PL panel with a 200A GE one and then replace the 200A breaker with this 175A breaker kit. It's more work , but worth it.

Line side taps are not permitted by Local AHJ. This seems to be the most convenient solution.

kbsparky 09-08-2012 10:51 AM

Square D makes 175 amp breakers for their load centers, or as a stand-alone disconnect. QOM2175VH and a QOM22225NS enclosure would do the trick

stickboy1375 09-08-2012 10:52 AM

Quote:

Originally Posted by kbsparky (Post 1005477)
Square D makes 175 amp breakers for their load centers, or as a stand-alone disconnect. QOM2175VH and a QOM22225NS enclosure would do the trick

I was thinking a disconnect also.... just has to be rated for service equipment, and then change all the GEC's and neutral grounding connections.

superduper 09-08-2012 02:58 PM

so if I get a $300 GE fusable disconnect like the one pictured below does it come with a neutral and a ground lug installed as well as MBJ? I'd rather stick with GE since I already have the breaker. I'm aware there are a few different 175A breaker manufacturers with enclosures, but all of these enclosures are huge 2 to 3 feet in size. Trying to keep it compact.

Wish I could see a photo of the insides of these disconnects. can't even pull up a manual on the internet. Anyone have a schematic of the insides of these things? Might have to swing by the local electrical supply house.



http://www.homedepot.com/catalog/pro...e31f83_300.jpg
http://www.homedepot.com/catalog/pro...e31f83_300.jpg

stickboy1375 09-08-2012 03:09 PM

Quote:

Originally Posted by superduper (Post 1005609)
so if I get a $300 GE fusable disconnect like the one pictured below does it come with a neutral and a ground lug installed as well as MBJ? I'd rather stick with GE since I already have the breaker. I'm aware there are a few different 175A breaker manufacturers with enclosures, but all of these enclosures are huge 2 to 3 feet in size. Trying to keep it compact.

Wish I could see a photo of the insides of these disconnects. can't even pull up a manual on the internet. Anyone have a schematic of the insides of these things? Might have to swing by the local electrical supply house.



http://www.homedepot.com/catalog/pro...e31f83_300.jpg
http://www.homedepot.com/catalog/pro...e31f83_300.jpg

You said you were an electrical contractor on Mike Holts forum... this should be pretty easy at this point.


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