Grounding Question- Breaker or Box

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  #1  
Old 04-30-15, 04:01 PM
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Grounding Question- Breaker or Box

Quick question. Is it sufficient to ground a new branch to a junction box or should it be grounded at the breaker panel?

The reason I ask is that my breaker panel is grounded, but none of the branches are grounded inside the panel. Rather the initial ground starts at the first junction box (the whole 'green screw' setup).

Depending on the answer, should I ground at the panel when adding a new breaker/branch?

Thank you.
 
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Old 04-30-15, 04:15 PM
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If there is no ground to the box by a ground wire or acceptable grounding path such as continuous metal conduit or modern metallic/armored cable (but mot old style BX without a bonding strip) then there is no ground and connecting to the box serves no purpose. Further code says a ground wire must originate at the panel.
 

Last edited by ray2047; 04-30-15 at 07:35 PM.
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Old 04-30-15, 07:34 PM
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should I ground at the panel when adding a new breaker/branch?
When installing a new breaker and new branch circuit, the ground wire (EGC) terminates on the grounded neutral bar unless it is a subpanel. If it is a subpanel, terminate the ground wire on the ground bar.
 
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Old 04-30-15, 09:13 PM
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Since none of the existing branches have grounds that terminate in the box, would it make sense to splice in grounds from the existing branches back to the neutral bar?

Also, just out of curiosity. Why terminate on the neutral rather than the ground?
 
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Old 04-30-15, 09:19 PM
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just out of curiosity. Why terminate on the neutral rather than the ground
In the first panel with an OCPD (Over Current Protection Devices such as breaker or fuse) ground and neutral are connected together and there is often no separate ground bar. Sub panels after the first OCPD do have a ground bar if installed by newer code cycles.
would it make sense to splice in grounds from the existing branches back to the neutral bar?
Yes or ground bar if it is a subpanel.
 
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Old 04-30-15, 10:51 PM
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Here's a couple of my panel.

The service disconnect is separate.

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Old 05-01-15, 05:43 AM
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It looks like you have metallic conduit which would provide the ground. Can you confirm this?
 
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Old 05-01-15, 12:09 PM
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Yes. There is steel conduit going to the panel. the other end terminates into the floor of the garage and is also connected to an incoming copper water pipe.
 
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Old 05-01-15, 12:20 PM
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You should not have electrical conduit going to a water line. The conduits I see all have branch circuit conductors in them.
 
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Old 05-01-15, 07:20 PM
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That is a subpanel. It appears the feeder to the subpanel is in conduit and the conduit is carrying the ground. It also appears you have a bonding bushing on the feeder conduit connector that is bonded to the ground bar installed at the bottom of the panel which grounds the panel box. The branch circuits don't have ground wires because the branch circuit conduits are carrying the ground from the grounded panel box to the boxes on the branch circuits.

Is it sufficient to ground a new branch to a junction box or should it be grounded at the breaker panel?
If the new branch circuit is cable (probably 12-2 or 14-2 NM-B cable aka romex), the ground wire should terminate on the ground bar at the bottom of the panel. If the new branch circuit will be installed in one of the existing conduits, the new circuit ground can be terminated at the junction box.
 
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Old 05-02-15, 05:40 PM
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Okay, I think this is where I'm getting confused. It's a sub panel because the main disconnect is separate from the distribution, correct?

If the new branch circuit is cable (probably 12-2 or 14-2 NM-B cable aka romex), the ground wire should terminate on the ground bar at the bottom of the panel. If the new branch circuit will be installed in one of the existing conduits, the new circuit ground can be terminated at the junction box.
Question about this. Why would a new branch/breaker/conduit require ground termination at the bar while the old ones don't? Change in code?

You should not have electrical conduit going to a water line
Sorry, should have been more specific. The ground in the panel is coming form the main disconnect. The condition/water/ground setup originates from the main. I can provide pictures if I'm not making sense.

Thanks all for your patience.
 
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Old 05-02-15, 06:47 PM
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You metallic conduit acts as the green grounding conductor. The new circuit can ground to the box and use the conduit back to the panel.
 
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Old 05-02-15, 08:20 PM
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Question about this. Why would a new branch/breaker/conduit require ground termination at the bar while the old ones don't? Change in code?
Go back and read again. IF.....and only IF a new circuit is run with CABLE (12-2 or 14-2 NM-B cable aka romex) the ground wire from the cable would terminate at the ground bar. I said nothing about a new circuit in conduit requiring a ground termination at the ground bar.
 
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Old 05-02-15, 10:16 PM
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Gotcha'. I got a confused at the exisiting conduit part since in my head I was thinking new conduit run, etc. Get it now that you were talking about straight romex. Thanks for followup.

I REALLY appreciate everyone taking the time to set me straight.
 
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