EGC with feeder wires

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socalelect

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hello forum this is my first post here ive been a longtime lurker , my name is steve . im not sure if im in the right spot of the forum or if i have titled this properly . i work for a company that provides installation and repairs to fire apparatus line voltage systems , i also deal with electrical maintence at my companys shop and offices . they have a Jman on staff but he is a real pita to deal with .
Heres the situation . They have a smaller building approx 500 feet from the main shop that is used as the welding and fabrication area .
currently they have power pulled out of the main panel on a 50 amp 2 pole CB 240v single phase . there is duplex air compressor in the welding area 2 240v single phase motors @ 5hp 28amps each , yes i know grossly overloaded at that , then they run a plasma cutter at the same time and cant seem figure out why the breaker trips , they just whine that they have to walk so far to reclose the cb

so basically i went to the jman and told him we needed to run new feeders for the sub at the weld shop , his solution was to pull 3
4 ought aluminum cables in line 1 line 2 neutral which for voltage drop sounds reasonable to me i havent done the math yet.

my issue with this and my question is , isnt there a egc required in the conduit with the feeders , when i asked the jman he anwser was drive 2 new ground rods , and connect the gec and bond the neutral and ground bar in the sub . it sounds fishy to me and i have had trouble locating the section in the nec that covers that
 
250.32(B)(1) Supplied by a Feeder or Branch Circuit. An equipment
grounding conductor, as described in 250.118, shall
be run with the supply conductors and be connected to the
building or structure disconnecting means and to the
grounding electrode(s). The equipment grounding conductor
shall be used for grounding or bonding of equipment,
structures, or frames required to be grounded or bonded.
The equipment grounding conductor shall be sized in accordance
with 250.122. Any installed grounded conductor
shall not be connected to the equipment grounding conductor
or to the grounding electrode(s).
Exception: For installations made in compliance with previous
editions of this Code that permitted such connection,
the grounded conductor run with the supply to the building
or structure shall be permitted to serve as the ground-fault
return path if all of the following requirements continue to
be met:
(1) An equipment grounding conductor is not run with the
supply to the building or structure.
(2) There are no continuous metallic paths bonded to the
grounding system in each building or structure involved.
(3) Ground-fault protection of equipment has not been installed
on the supply side of the feeder(s).
If the grounded conductor is used for grounding in accordance
with the provision of this exception, the size of the
grounded conductor shall not be smaller than the larger of
either of the following:
(1) That required by 220.61
(2) That required by 250.122
 
socalelect said:
= isnt there a egc required in the conduit with the feeders
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yes. unless the conduit qualifies as EGC in 250.118

socalelect said:
= when i asked the jman he anwser was drive 2 new ground rods , and connect the gec and bond the neutral and ground bar in the sub . it sounds fishy to me and i have had trouble locating the section in the nec that covers that
Click to expand...

this would violate 250.24(A)(5)
 
The method he is wanting to use was allowed for years until a couple of code cycles ago. Since then it's considered a code violation. I wouldn't advocate doing it this way, but I also wouldn't use any sleep over his installation.
 
paul said:
The method he is wanting to use was allowed for years until a couple of code cycles ago. Since then it's considered a code violation. I wouldn't advocate doing it this way, but I also wouldn't use any sleep over his installation.
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Well, if by a couple you mean 13, maybe:
NEC 1965 said:
210-7. Where a feeder supplies branch circuits in which grounding conductors are required, the feeder shall include or provide a grounding means to which the grounding conductor of the branch circuit shall be connected.
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I haven't looked back to see when that method was "allowed", but it wasn't in my lifetime.

And you might want to consider that one carefully before sleeping tonight, actually. While a building like that likely has numerous functional grounding paths, we don't know that from the info provided so far.
 
Volta said:
Well, if by a couple you mean 13, maybe:


I haven't looked back to see when that method was "allowed", but it wasn't in my lifetime.

And you might want to consider that one carefully before sleeping tonight, actually. While a building like that likely has numerous functional grounding paths, we don't know that from the info provided so far.
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Uh, the OP said it was a separate building. It would depend on what code cycle they are under, to determine if the j-man was right or not.
 
a separate egc should be ran (unless the conduit serves this purpose) and should be seperate from the neutral in the subpanel. chances are good that you will need to bond the building steel as well (to the egc, not the neutral)
 
just flipped through the code book and 250.32B words it pretty nicely. I believe you still need ground rods at the separate building which the feeder supplies
 
duck_huntr85 said:
a separate egc should be ran (unless the conduit serves this purpose) and should be seperate from the neutral in the subpanel. chances are good that you will need to bond the building steel as well (to the egc, not the neutral)
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And yet the new code says you cannot use an EGC to bond various pieces of the GES together.
 
Volta said:
Well, if by a couple you mean 13, maybe:


I haven't looked back to see when that method was "allowed", but it wasn't in my lifetime.

And you might want to consider that one carefully before sleeping tonight, actually. While a building like that likely has numerous functional grounding paths, we don't know that from the info provided so far.
Click to expand...

The ability to use the the grounded circuit conductor as the equipment ground and install a new bonding jumper and grounding electrode system at the load end only applied to feeders supplying separate buildings or structures. This was no longer allowed in 2008 NEC (maybe 2005 but pretty certain it was 2008) Feeder supplying loads in same building or structure has required separate EGC for long time - possibly always required it.
 
conduit will be pvc so no luck there , i just got out of a meeting with the owners , and what do ya know we will be running a EGC with the feeders .
 
kwired said:
The ability to use the the grounded circuit conductor as the equipment ground and install a new bonding jumper and grounding electrode system at the load end only applied to feeders supplying separate buildings or structures. This was no longer allowed in 2008 NEC (maybe 2005 but pretty certain it was 2008) Feeder supplying loads in same building or structure has required separate EGC for long time - possibly always required it.
Click to expand...

You are correct that 2008 made the change requiring an equipment grounding conductor be run with a feeder to a separate structure.

The 1999, 2002 & 2005 NEC allowed the grounded conductor to be bonded to the disconnecting means and grounding electrode at the separate structure as long as there were no continuous metallic paths bonded to the grounding system in each structure.

The 1996 required the grounded conductor to be bonded to the separate disconnect and grounding electrode, with the exception of not requiring the grounded conductor bond when a equipment grounding conductor is run with the feeder for the purposes of grounding any non-current carrying metal equipment, interior metal piping, etc., at the separate structure. Interesting, nothing prohibited running an egc with the feeder and bonding both the egc and grounded conductor in the 1996 code.
 
I can't count the number of times I've read a thread, got all fired up to comment that everybody is lost, to realize I had been reading everything everybody was saying wrong. It's weird. :cool:
 
Volta said:
Well, if by a couple you mean 13, maybe:


I haven't looked back to see when that method was "allowed", but it wasn't in my lifetime.

And you might want to consider that one carefully before sleeping tonight, actually. While a building like that likely has numerous functional grounding paths, we don't know that from the info provided so far.
Click to expand...

I'm still sleeping comfortably tonight with my response. :)
 
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