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Discussion Starter · #1 ·
I have a question:

I recently looked at an existing service (with a generator panel) that had a main breaker panel with a main lug only panel right beside it. The main lug only panel is served by the main breaker panel (through a breaker located in the main breaker panel) and also by the generator.... But I don't want to get too hung up on that. My question is, can I have a main lug panel installed, or, does it have to have a "main breaker" also? I am thinking that the main lug panel can be disconnected by the breaker located in the main breaker panel, or, by the generator transfer switch (which is also located adjacent to the two panels mentioned above) and, therefore, I think we are okay with a main lug only panel installed. I just want to make sure it is not a code violation to install a main lug only panel with more than 6 breakers installed, (I don't want to violate the 6 disconnect rule). There is no space to add another breaker to feed (or backfeed) the main lug panel.
 

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You got kinda wordy there but I'll give it a try.
You have a main breaker panel feeding a main lug panel.
You want to remove the main breaker panel and install an ATS for a generator, feeding the main lug panel.
If this is the case, the ATS must be service entrance rated.

If this is not the case, I'll be in my tent.
 

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The six disconnect rule is for services. You already have a disconnect means from the POCO side. You also said you have a disconnecting means for the generator side.
 

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You're not very clear on what you are asking.

Are you asking if the existing main lug panel is okay in this situation?

Are you asking if it's okay to install an additional main lug panel fed by the main lug panel that's already there?
 

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Discussion Starter · #7 ·
Sorry I wasn't clear, I was asked to bring the installation up to code and to make a few corrections. There are a couple of corrections that I did not mention. - Anyway, I just didn't know if having a main lug panel there would raise an issue with the inspector. (If I make the corrections that need to be made I am going to get a permit.) I want to leave the installation "as is" as much as possible. I think it's okay but I just want to make sure. I don't recall ever having installed a main lug panel like that myself. The poster who said if it isn't legal in this situation then when would it be makes a good point. I just have never done it this way; I don't recall ever having used a main lug panel. - Thanks for all your input, I do appreciate it.
 

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The six disconnect rule is for services. You already have a disconnect means from the POCO side. You also said you have a disconnecting means for the generator side.
The six throw rule does not only pertain to services. If you are running power to a panel in a seperate structure for instance you would not be required to have a main if you limit the ocpd's to six.

As far as the op described the situation he is not required to have a main in the back up panel. He can even have more than six disconnects due to the fact the transfer switch is a disconnect (assuming the generator provides overcurrent protection and it is a manual transfer switch).
 

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Discussion Starter · #9 · (Edited)
It's an automatic transfer switch... but I think that you can disconnect it with a push of a button. There is over-current protection on the generator but the generator and the over-current protection with it are outside.... I've been checking into this and I think I am okay with what I have as long as that generator switch (automatic transfer switch) will work as a disconnect.... At this point, that is the thing I'm most unsure about. Everything else I think is OK.... Thanks for your replies.
 
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