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Steve G.
Steve G., Electrical Engineer
Category: Electrical
Satisfied Customers: 17987
Experience:  Spent 20 years as an Electrical Engineer, designing electrical plans and specifications.
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I am installing an eaton 100 amp main breaker panel as an indoor

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I am installing an eaton 100 amp main breaker panel as an indoor sub panel. I have power to the main breaker but it is not energizing the rest of the panel. Should I be using a main lug instead?

Hello there and welcome to Just Answer. My name is XXXXX XXXXX I will be assisting you today. I am an engineer with over 30 years of electrical and electronic training, repair and installation experience. I will try and answer your question accurately and precisely so that we can get you on your way.

Ok, so you have a sub panel with a 100A main breaker. Assuming that this is a residential application, you will have two hot conductors and a neutral (disregard ground for now).

At the top of the breaker (the hot side), what is the voltage between each hot and the neutral? I need two numbers.

Please let me know so that we can continue.



Customer: replied 4 years ago.

I am driving to the location i will let you know in a couple of minutes


Ok, I'll be here.
Customer: replied 4 years ago.




12.08 hot

7.24 on nuetral


That's on the hot side - on the incoming conductors to the breaker?

You should have 120V both from L1 to N and from L2 to N.

Can you describe what you did at your main panel? I assume that you have a 100A 2 pole breaker feeding the main breaker in your new panel?

I also assume that you pulled over two hots, a neutral and a ground? You terminated the two hots into the top of the main breaker, the neutral to the neutral bar and the ground to the ground bar?

By the way, you need to remove the bonding screw or strap between the neutral and ground bars in that sub panel.

Please let me know so that we can continue.



Customer: replied 4 years ago.

I just removed the bonding screw, iam repacing an old screw in type panel with the orange and blue fuses, the 2 hots neutral and ground are connected as you directed.i have 115v on one hot and 115v on the othrer


Ok, then that sounds right.

When you are confident that everything is correct, turn on the new main breaker and your panel should be energized.

I'll be here if you need further help with this issue. Please let me know.



Customer: replied 4 years ago.

the ground (very thick aluminum looking) does not reach the ground bar. I screwed it to the box itself. The top hot wire is red the other is black. Both are connected to the main breaker in the sub-panel.

Ok, and between the two (black and red) you should have 240V or thereabouts.

Do you?

If so, turn on the breaker and the sub panel should be energized.


Customer: replied 4 years ago.

i get 242v on the black and red combined, i can jump fron the hot on the breaker to another breaker and it works. the main breaker is not sending energy to the rest unless i jump it.


Is it possable that the new panel box is just bad? I replaced the 100 amp breaker that came installed in the panel with a new one, no bondidng screw is in use

Is the breaker 'on'?

Can you try the switch in both positions please?

Customer: replied 4 years ago.

Yes I have turned the 100 amp breaker in on and off positions. the outside main is on and sending power to the main breaker inside but it is not sending juice to the rest of the panel.

That's odd.

So there is no voltage on the copper bussing of that panel, but the breaker is connected to it on its load side? And you have the breaker on and you have 240V on the Line side of the breaker?

Customer: replied 4 years ago.

there is a copper strip on the outside panel with the ground bar, however I do not see any copper strip in this eaton panel inside the house

The branch circuit breakers mount to the copper bus. It may be tinned so that it looks silver but it is copper. The main breaker has your feeders in one side and the other side likely stabs on to that bus.

How about a photo of that sub panel with the breaker attached? You can upload it here using the paper clip icon or you can email it to [email protected] attn: Steve555

Then I can see what's going on here.

Customer: replied 4 years ago.

i emaile the pictures...the panel is being installed up side down du to not having enough existing wire that ran to the bussman type screw in fuses


Ok, when I receive the photo from my admin, I will reply back to you.

This may take an hour or more as it is Sunday.

Customer: replied 4 years ago.

I'm getting access denied but here's the links to the photos

Ok, disconnect the 100A breaker and remove it from the panel. Obviously, you will need to kill the upstream breaker to make it safe.

Get your meter and set it to ohms.

On the back of the breaker are the two 'stabs' that connect the breaker to the panels busbars, one for each 'half' of the breaker. I want you to click the breaker on and then measure the resistance between the screw of each phase and the corresponding bus stab. With the breaker handle in the on position, you should get close to zero ohms for each half of the breaker.

Can you try that please and let me know.

Customer: replied 4 years ago.

We have totally remove this main panel breaker and are returning it to the store. Should we get a main lug panel instead for easier installation? What brand would you recommend.

Square D/Eaton is fine. Cutler Hammer, GE, Westingouse etc.

I think maybe the breaker was bad.

I like to have a main breaker on any panel. Have the store test the main breaker for you.


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