number of grounds to panel?
#1
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number of grounds to panel?
Pulling 12 awg conductors thru 3/4" romex from the panel to a pull box:
8 hots, 4 neutrals (all multi-wire circuits). So 8 circuits.
1 ground from the panel to the pull box.
In the pull box, tie the branch circuit grounds together, along with the pull box ground, and the panel ground.
Basically the grounding 'bar' is now in the pull box.
Legal?
8 hots, 4 neutrals (all multi-wire circuits). So 8 circuits.
1 ground from the panel to the pull box.
In the pull box, tie the branch circuit grounds together, along with the pull box ground, and the panel ground.
Basically the grounding 'bar' is now in the pull box.
Legal?
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WHAT'S THE QUESTION !?
How do you pull thru- Rx.?
What is the panel ground you speak of?
The ground in the conduit only has to be as big as the largest current carring conductor. You may not have room if you put the ground bar in that pipe.
Back up and try again with the question.
How do you pull thru- Rx.?
What is the panel ground you speak of?
The ground in the conduit only has to be as big as the largest current carring conductor. You may not have room if you put the ground bar in that pipe.
Back up and try again with the question.
Last edited by DIYaddict; 08-15-06 at 09:15 PM. Reason: removed quote as it's unnecessary to quote the entire post
#3
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my bad.
Of course not romex. just 12awg wire thru 3/4" EMT.
Run only one ground (12awg) from the ground bar at the main panel to the pull box. At the pull box, connect all grounds from the branch circuits, along with the pull box grounding wire.
Question is it ok to run only one ground wire from the grounding bar in the main panel, then connect all the branch circuit grounds to it downstream of the main panel?
Of course not romex. just 12awg wire thru 3/4" EMT.
Run only one ground (12awg) from the ground bar at the main panel to the pull box. At the pull box, connect all grounds from the branch circuits, along with the pull box grounding wire.
Question is it ok to run only one ground wire from the grounding bar in the main panel, then connect all the branch circuit grounds to it downstream of the main panel?
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Now thats a better question.
Yes ,
the ground must be large enough for the largest current carrying conductor.
You DO NOT need a ground for EACH CKT.back to the panel.
If each cable has a ground comming back to the "JB", Make sure you have a termination device to handle them (burndey etc.).
They all should be tied together.
Yes ,
the ground must be large enough for the largest current carrying conductor.
You DO NOT need a ground for EACH CKT.back to the panel.
If each cable has a ground comming back to the "JB", Make sure you have a termination device to handle them (burndey etc.).
They all should be tied together.
Last edited by lectriclee; 08-15-06 at 09:41 PM.
#5
Yes that's perfectly legal. When you pull a ground wire with multiple circuits all that is required is that the equipment ground is sized to the largest overcurrent device protecting those circuits. So if your largest breaker is 20 amps then your #12 awg cu ground wire is fine. If it ws 30 amps then #10 cu would be your ground wire size.
Code reference is NEC 250.122 (C)
Be careful of derating problems if you get over 9 current carrying #12's in the raceway.
Roger
Code reference is NEC 250.122 (C)
Be careful of derating problems if you get over 9 current carrying #12's in the raceway.
Roger
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Originally Posted by Roger
Yes that's perfectly legal. When you pull a ground wire with multiple circuits all that is required is that the equipment ground is sized to the largest overcurrent device protecting those circuits. So if your largest breaker is 20 amps then your #12 awg cu ground wire is fine. If it ws 30 amps then #10 cu would be your ground wire size.
Code reference is NEC 250.122 (C)
Roger
Code reference is NEC 250.122 (C)
Roger
Thanks for the clarification.
Now you and the others know why I'm not known for my technical wrighting.