grounding outside the conduit

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vortiz

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Somebody asked me if the ground wire could be ran outside the conduit. I answered no because it is my understanding that all the wires should be inside the same conduit. They ran 4" rigid conduit parallel feeds and no ground, but now they want to add a ground wire. I just want to know if I am right or wrong.
 
It must go within the conduit. Take a look at 250.134(B). What's wrong with using the RMC as the EGC? This will be much better than any wire type EGC.
 
vortiz said:
Somebody asked me if the ground wire could be ran outside the conduit. I answered no because it is my understanding that all the wires should be inside the same conduit. They ran 4" rigid conduit parallel feeds and no ground, but now they want to add a ground wire. I just want to know if I am right or wrong.
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Do they need an equipment grounding conductor? The pipe itself is a ground.
 
Oh NO!

Oh NO!

Isn't this horse dead yet:wink: ??? I am with the rest of you in this scenario. This is rigid, why the need for an extra ground pull all of a sudden?
Curious:)
 
76nemo said:
Isn't this horse dead yet:wink: ??? I am with the rest of you in this scenario. This is rigid, why the need for an extra ground pull all of a sudden?
Curious:)
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It may be speced.
 
If you have to get tough with them ... start with 250.118(2) Same in the 05 as in the 08.

Next thing you know, they'll want green tape on the pipe.
 
newbie

newbie

Just looking in for the first time but why is it that now engineers are now running grounds on a new service from a pad mount transformer to the main breaker. Landing grounds on XO in the pad mount. The ground triad already goes to both places. Or am I missing something here?
 
vortiz said:
Somebody asked me if the ground wire could be ran outside the conduit. I answered no because it is my understanding that all the wires should be inside the same conduit.
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You're mostly right - check out 250.102 for one case where the EGC can be replaced by an Equipment Bonding Jumper, which can run outside the conduit for short lengths. I've never had occasion to use that, myself, though.
 
eo283 said:
Just looking in for the first time but why is it that now engineers are now running grounds on a new service from a pad mount transformer to the main breaker. Landing grounds on XO in the pad mount. The ground triad already goes to both places. Or am I missing something here?
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Either you're missing something, or they are specifying a code violation. 250.24(B) will create a 250.6 violation, if EGCs are run with the service conductors.

Could the installation you're considering be outside the scope of the NEC (90.2)?
 
infinity said:
It must go within the conduit. Take a look at 250.134(B). What's wrong with using the RMC as the EGC? This will be much better than any wire type EGC.
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bout 40 years from now it will just be rust pockets, is that a good egc:grin:
 
So you guys are saying the EGCs that are very common for bonding equipment together in the field is not allowed by code?

Just about every chemical plant I have been in has a #2 (or better) ground wire run around to all the equipment separately from the EGC run with the power conductors.
 
Bob,
Just about every chemical plant I have been in has a #2 (or better) ground wire run around to all the equipment separately from the EGC run with the power conductors.
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That is not a violation as it is not covered by the NEC (assuming that a proper EGC has been installed for the circuit). I know it is a common practice, but I don't see it serving any purpose...probably one of those specs that was written by the copper industry.
Don
 
georgestolz said:
How are those extra EGCs routed? Where do they go?
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seems to depend on when they were run. if they were an add on, they seem to go where ever it is convenient. sometimes along an existing conduit or cable tray, other times underground.

mostly they fan out and bond all the pieces of equipment. usually they go to every MCC and panelboard as well. Often it seems the local MCC is where it fans out to the equipment in the area.
 
petersonra said:
So you guys are saying the EGCs that are very common for bonding equipment together in the field is not allowed by code?
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Not when that EGC would carry normal neutral current. On the line side of the main disconnect, the system neutral should be doing double duty as the EGC.

There should not be a separate service EGC, because the required neutral bond at the disco would parallel the EGC with the service neutral. Electrodes are okay, since the earth is not considered a conductor

Just about every chemical plant I have been in has a #2 (or better) ground wire run around to all the equipment separately from the EGC run with the power conductors.
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Yes, but were the load ends of feeder neutrals bonded to this EGC? I'll bet not. There's no problem with redundant EGC's, only parallel neutral-current pathways.
 
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