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Discussion Starter #1
this subpanel is marked on the box as 2-slot, 4-circuit (2 double pole breakers). the grounding bus, as i see, has two lock screws, one for the ground coming in from the main panel, one to go to the grounding rod (is this correct?) and 4 slots, which corresponds to the number of circuits. but what am i supposed to do with the neutral coming in in the neutrals from the 4 circuits supported?

thanks
 

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Actually being a sub panel the neutral and ground needs to be separate. The bus supplied should be used as the neutral. Leave the screw out that bonds it to the metal case. You need to go and buy a ground bus kit that will fasten direct to the metal box. I believe it will fasten to that raised lump in the upper right.
 

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I am no electrician, but I believe that the 2 lock screws you are referring to are for the nuetral coming from the main panel. You need to run 4 wires from your main panel to this sub. 2 hot conductors to the screws above where the breakers lock into, 1 nuetral to either one of the 2 lock screws on the side, and 1 ground from the ground bar in your main panel to a separate isolated grounding bar in your sub panel. You will need to buy the ground bar separately.

Eric
 

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That is the neutral bar. If you do a continuity check, it should be isolated from the box. You need to install a separate ground bar, mounted directly to the box. Make sure it’s capable of accepting the gauge sizes you need. Standard size holes in the bar should be okay. #8 I think you said was coming from the main panel, and you’ll need another hole for #8 copper to the grnd rods. Detached shed, right? Plus enough holes for the branch circuits you’re running.

PS. You need tandem/twin breakers if you want 4-120v circuits. Commonly a double pole breaker=2 pole breaker=240V breaker.
 

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Discussion Starter #5
You need to go and buy a ground bus kit that will fasten direct to the metal box. I believe it will fasten to that raised lump in the upper right.
I got one by Eaton but the screw doesn't fit in the hole in the lump you're referring to. I will return it and look for a Square D one, which is the brand of the subpanel.

does anybody possibly see another docking for a grounding bus in the picture?
 

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See what the instructions with the bar say. Might have to drill a hole or 2 and bolt it in.
 

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It is possible that you find the neutral assembly is bonded to (has essentially resistance free continuity with) the body (frame; can) of the panel. If so, look for a screw which when undone removes that continuity.

The bonding screw would be left in place for 240 volt only panel usage (no neutral) in which case the neutral assembly is used for ground wires (grounding conductors).
 

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Discussion Starter #9
finally, my question is why don't they include a grounding bus with a subpanel ?? DUH. it's not like you won't need it. sounds to me like selling a car without a steering wheel... :wallbash::bangin:
 

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Because if it is not used a sub panel then you don't need it. Or if it is only used a 240 volt disconnect, there is no neutral so you can use the existing one for ground.
 

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finally, my question is why don't they include a grounding bus with a subpanel ?? DUH. it's not like you won't need it. sounds to me like selling a car without a steering wheel... :wallbash::bangin:
Another way to save money in manufacturing, because it's not always needed, as Joe mentioned.

Wanna buy a steering wheel? :)
 
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