# Double tapped 100a main to 2 100a sub panels



## HackWork (Oct 2, 2009)

It might be OK depending on the exact situation, which I am unsure if by your description.

You can have (6) 100A main breaker panels on (1) 100A service as long as the calculated load is 100A or less.


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## MDShunk (Jan 7, 2007)

Was it overloaded? I dunno. My psychic powers suck. What result did you get when you performed the demand load calculation?


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## Solarelectrician (Sep 1, 2018)

2 FULL sub panels on 100a main service. ‘This is for solar and I will need to back feed 30a as well. Thanks for the smart ass remarks.


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## MDShunk (Jan 7, 2007)

Solarelectrician said:


> 2 FULL sub panels on 100a main service. ‘This is for solar and I will need to back feed 30a as well. Thanks for the smart ass remarks.


You clearly do not understand what a demand load calculation is and how important it is to provide your answer. It matters not one bit how full those panels are or what size branch breakers are in them. A demand load calculation (and a panel demand load calculation for each panel) is the only way you will ever know. My gut feeling so far, without enough information, is that this is quite likely to be a compliant installation.


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## HackWork (Oct 2, 2009)

Solarelectrician said:


> 2 FULL sub panels on 100a main service. ‘This is for solar and I will need to back feed 30a as well. Thanks for the smart ass remarks.


Whether the panels are full or not is meaningless. I have seen houses with a total of 4 panels and 70 circuits have a load of 30A and houses with a total of 8 circuits have a load of 140A.

I am not sure who are you are talking to or what smart ass remarks you speak of.


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## cabletie (Feb 12, 2011)

I'm not sure I understand either. 

If I had a 100A main breaker I could feed as many subpanels as I wanted off of it. It would be fused at 100A

What's a 50 20 split? Is that a quad breaker? Is that a split buss panel?


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## HackWork (Oct 2, 2009)

cabletie said:


> I'm not sure I understand either.
> 
> If I had a 100A main breaker I could feed as many subpanels as I wanted off of it. It would be fused at 100A
> 
> What's a 50 20 split? Is that a quad breaker? Is that a split buss panel?


Very true.

In his situation it sounds like they tapped into the 100A service conductors to add a second 100A panel. But that is still allowed as long as the service conductors can handle the calculated load. It's the way that multi-family dwellings do it, I often put 4-6 100A panels on 200A service conductors.


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## Solarelectrician (Sep 1, 2018)

Unfortunately, I don’t have the demand load calculations. I am a solar electrician and when I leave the job the electrical needs to be up to code. Both panels are at the 125% capacity and has a quad 50/20 on the main as well.


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## HackWork (Oct 2, 2009)

Solarelectrician said:


> Unfortunately, I don’t have the demand load calculations. I am a solar electrician and when I leave the job the electrical needs to be up to code. Both panels are at the 125% capacity and has a quad 50/20 on the main as well.


Then you have nothing to worry about. Let the electrician handle it.


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## wildleg (Apr 12, 2009)

cabletie said:


> ...
> 
> What's a 50 20 split? Is that a quad breaker? Is that a split buss panel?


https://www.westsidewholesale.com/siemens-q22050ct2.html?gclid=CjwKCAjw8ajcBRBSEiwAsSky_fZbwPjBIrTDmFb5kPWN_DC-rcbFvTiO5UZNCRWkGKetONkuZpLNfRoCzUUQAvD_BwE


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## Solarelectrician (Sep 1, 2018)

Maybe this will help.


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## MDShunk (Jan 7, 2007)

Solarelectrician said:


> . Both panels are at the 125% capacity and has a quad 50/20 on the main as well.


Slow your roll. You have absolutely no way to know that. You did not perform a demand load calculation for either the service or each panel. Declaring them to be at 125% capacity is a total WAG on your part.


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## Switched (Dec 23, 2012)

That looks like a Cali abomination.


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## MDShunk (Jan 7, 2007)

Solarelectrician said:


> Maybe this will help.


Yes, indeed. Looks completely compliant. A 100 amp main, tapped on the load side to go a few different places. A 50-20 quad to go a couple more places. That's three disconnects, which is less than 6, so that's still compliant. 

What's the issue again? Oh, lack of a demand load calculation. Yeah, you should probably do one.


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## Switched (Dec 23, 2012)

What's wrong with it?

The only thing off the top of my head would be whether or not the quad breaker can be there. Some of those panels are not rated for it, 4 space/4 circuit, some are 4 space 8 circuit, so it could be fine.


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## cabletie (Feb 12, 2011)

Milbank makes load tap lugs for their meter sockets. 

The resident solar guy hasn't posted in a while, but I saw him run another riser up and splice to the drop. I'm not sure if that's an option.


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## HackWork (Oct 2, 2009)

The 100A breaker is protecting the 2 subpanels, that is fine. 

As for the additional quad breaker, do you know the rating of that meter panel?


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## MDShunk (Jan 7, 2007)

HackWork said:


> The 100A breaker is protecting the 2 subpanels, that is fine.
> 
> As for the additional quad breaker, do you know the rating of that meter panel?


From the depth of the revenue meter, that's a CL200 meter, so it's almost certainly a 200-225 amp rated meter-main.


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## Solarelectrician (Sep 1, 2018)

You can’t have one breaker for two separate sub panels. I’m fixing that by adding another sub and adding 2 individual 100a breakers.


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## cabletie (Feb 12, 2011)

He means he can't add a larger breaker to backfed the panel with solar. Has to be under 125%. Maybe he needs to back feed with a fourty amp solar breaker or something.


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## Solarelectrician (Sep 1, 2018)

The meter panel is 100a and is my concern


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## MDShunk (Jan 7, 2007)

Solarelectrician said:


> You can’t have one breaker for two separate sub panels. I’m fixing that by adding another sub and adding 2 individual 100a breakers.


Wow. Just wow. Yes, you can. You can have one breaker for 100 subpanels and be perfectly compliant. There's nothing to fix. You're costing someone some money unnecessarily. 

Quick question: You an electrician?


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## HackWork (Oct 2, 2009)

Solarelectrician said:


> You can’t have one breaker for two separate sub panels. I’m fixing that by adding another sub and adding 2 individual 100a breakers.


Why not?


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## Solarelectrician (Sep 1, 2018)

New Commercial and solar mostly. I also worked as an engineering tech at Tesla. So if you want to talk some theory and circuits, I’m down. No, I’m not proficient in residential. Just looking for some advice not your criticism.


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## wildleg (Apr 12, 2009)

this thread is dildos. I thought the forum was for electricians.

if this is typical of the solar installers, it is scary.


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## Solarelectrician (Sep 1, 2018)

Because it’s in the code book.


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## HackWork (Oct 2, 2009)

Solarelectrician said:


> New Commercial and solar mostly. I also worked as an engineering tech at Tesla. So if you want to talk some theory and circuits, I’m down. No, I’m not proficient in residential. Just looking for some advice not your criticism.


Dude, you have such a bad attitude.

If you had a clue as to what you were talking about, you wouldn't look so bad.


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## HackWork (Oct 2, 2009)

Solarelectrician said:


> You can’t have one breaker for two separate sub panels. I’m fixing that by adding another sub and adding 2 individual 100a breakers.





HackWork said:


> Why not?





Solarelectrician said:


> Because it’s in the code book.


Yet you can't show me which article, can you? :vs_laugh:


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## Switched (Dec 23, 2012)

Solarelectrician said:


> Because it’s in the code book.


But where?


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## MDShunk (Jan 7, 2007)

Solarelectrician said:


> New Commercial and solar mostly. I also worked as an engineering tech at Tesla. So if you want to talk some theory and circuits, I’m down. No, I’m not proficient in residential. Just looking for some advice not your criticism.


Forgive me, but the stuff you're asking about is so fundamental and elementary. It's as if you just told me you're a prize winning author in one breath, and asked me what comes after the letter "C" in the alphabet in the next breath. 

What state do you operate in? I'm against licensing requirements so I won't hold that against you, but I'm also against incompetence.


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## MDShunk (Jan 7, 2007)

Solarelectrician said:


> Because it’s in the code book.


Wow again. You inventing your own code book as you go?


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## Switched (Dec 23, 2012)

wildleg said:


> this thread is dildos. I thought the forum was for electricians.
> 
> if this is typical of the solar installers, it is scary.


This is quite typical of solar installers in Cali... The stuff I run across on a daily basis is quite comical.


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## MDShunk (Jan 7, 2007)

Thanks for posting on ElectricianTalk.com. The Moderators of this forum would prefer if you post Do It Yourself related topics on our sister site www.DIYChatroom.com 

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## readydave8 (Sep 20, 2009)

Thread still open?

Just want to remind OP to try learning by listening rather than by talking. Advice that I don't always follow, but always should!


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## readydave8 (Sep 20, 2009)

Solarelectrician said:


> Unfortunately, I don’t have the demand load calculations. I am a solar electrician and when I leave the job the electrical needs to be up to code.


Not sure if both sentences can work in relation to each other

In other words, perhaps you can have one or the other, but not both?


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## frenchelectrican (Mar 15, 2007)

I am going close this thread due that solar dude not coming up with correct code numbers so .,

If that solar dude have found the dammed code numbers he can start the new thread on that.


sorry solar dude.,, few guys did make a very good legit points there.,,,,


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