# Sharing ground on multiple circuits (NEC)



## iwire (Jun 17, 2014)

Hi Question.

I have a panel runs to the mid point (a housing that is grounded) to multiple equipment.

Let's say I have 10 equipment that will have 2 conductors each (hot and neutral) and they are connected on the same ground wire to the mid point ground bar.

The ground bar is connected to the grounding system within the housing and also tied back to the panel

Can I do that per NEC?

Each conductor only #10 or #12 pending on the distance and derating. Load is only 2-3A each....and all the equipment are connected to individual 20A breaker.


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## iwire (Jun 18, 2014)

As long we size the ground according the 250.xx


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## jglavin PE (Jun 19, 2014)

It sounds like your ground bar is connected to some kind of grounding electrode system in the housing, so I would be inclined to say no, you can't use it as an equipment ground because you have the possibility of a ground loop from the housing ground back to the main grounding electrode.


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## Ship Wreck PE (Jun 19, 2014)

You got pics??


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## iwire (Jun 20, 2014)

jglavin said:


> It sounds like your ground bar is connected to some kind of grounding electrode system in the housing, so I would be inclined to say no, you can't use it as an equipment ground because you have the possibility of a ground loop from the housing ground back to the main grounding electrode.


There are grounding system within the kiosk that specifically for the equipment within the area. I think misunderstood on my initial statement.

The ground bar should be connected to grounding system within the area. It should be only tied back to the grounding on the main. The equipment are grounded within the grounding area (casing) etc. but not tied to the main system.

No pictures..sorry...


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## jglavin PE (Jun 20, 2014)

The code requires each branch circuit to have an equipment ground (either a wire, or conduit, or cable tray as in 250.120A), they can be shared when they are in the same raceway. If all the 20A circuits are in one raceway then you just need one ground. If circuits are fed to a separate building, you also need a method of simultaneous disconnect for all current carrying conductors entering the building.


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## iwire (Jun 20, 2014)

jglavin said:


> The code requires each branch circuit to have an equipment ground (either a wire, or conduit, or cable tray as in 250.120A), they can be shared when they are in the same raceway. If all the 20A circuits are in one raceway then you just need one ground. If circuits are fed to a separate building, you also need a method of simultaneous disconnect for all current carrying conductors entering the building.


Each equipment has their own grounding for equipment. I am talking about the feed...1 hot, 1 neutral and 1 shared ground.

All equipment are within the same vicinity. I thought I read it somewhere, shared ground as long it's on different phases...

Similar to Edison Circuit


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## jglavin PE (Jun 20, 2014)

Yes, you can share a ground, see 250.122C


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## iwire (Jun 20, 2014)

jglavin said:


> Yes, you can share a ground, see 250.122C


cheers...that what I thought..just want a second opinion lol


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