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youngfield
Oct 30, 2009, 10:53 AM
Hi -

I'm in Colorado and about to do an electrical service panel upgrade along with a sub panel install. (I should note here that I am an electrician - Australian, so the rules I'm used to are different here in the US).

I've applied for and received the relevant permit from the city, but want to make sure I get everything done properly first time so as to not waste the inspector's time and such.

1. I'll be replacing the current 100 amp service panel with a new 200 amp service panel. Was planning to use a GE brand panel. No problems there?

2. I want to install a separate 200 amp sub panel in my workshop to run wood working equipment. Can I install a set of 100amp breakers in the main panel to run to the sub panel, thus giving me the 200 amp at the sub panel?

Thanks Robert

tkrussell
Oct 30, 2009, 11:50 AM
My answers follow your questions:

1. I'll be replacing the current 100 amp service panel with a new 200 amp service panel. Was planning to use a GE brand panel. No problems there?

GE is a widely popular product. No problems.


2. I want to install a separate 200 amp sub panel in my workshop to run wood working equipment. Can I install a set of 100amp breakers in the main panel to run to the sub panel, thus giving me the 200 amp at the sub panel?

Please explain this. A set of 100 amp breakers to get 200 amp? You need a 200 amp breaker to protect a 2oo amp panel.

youngfield
Oct 30, 2009, 11:54 AM
Hi tkrussell

Sorry - goof on my part - I meant to write.. "200amp breakers in the main panel to run to the sub panel, thus giving me the 200amp at the sub panel". I should have re-read my original post. Sorry.

So... 200amp main panel with 200amp breakers feeding panel, and a set of 200amp breakers in the main panel feeding to the sub panel. Would that be acceptable for code? Thanks

Robert

tkrussell
Oct 30, 2009, 02:33 PM
Need a 2 pole 200 amp breaker as the main. You can use another 200 amp brekaer to feed a sub. Keep in mind, the service entracne will be a three wire, and after the main the feeder will be a 4 wire.

youngfield
Oct 30, 2009, 02:36 PM
Thanks tkrussell - I think you've answered my questions very nicely. Appreciate your help.

I hope I understand the three wire main (2 x hots and neutral) and the four wire feed (2 x hots, neutral and ground).

Robert.

KISS
Oct 30, 2009, 05:20 PM
Problem is, you may no be able to find a 200 A breaker for the panel. You may be limited to 100 or 125 A max.

Nonetheless, you can still use a 200 A main breaker sub-panel fed with 100-125 A. The wire would be sized for based on the feeding breaker.

You keep the neutrals separate in the sub. Remove the grond bonding screw ans purchase a ground lug kit when main breaker panels are used as subs.

A ground rod is required if he structure is detached.

youngfield
Nov 2, 2009, 03:41 PM
Yep - I think it is going to be hard to get a 200amp to feed the sub - so I'm going to use a 125A and a 125A sub. Don't really need 200 at the sub.

Thanks guys.
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