Sub panel replacement.

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arnettda

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I have a sub panel that needed to be replaced. It was feed with a three wire system. Wire will not budge to try to pull in a fouth wire. No ground rods driven for sub panel. bonding jumper installed in sub panel. How would you proced to replace panel. Main panel in attached garage feeds sub panel in basement through slab.
I replaced panel and right now it is a three wire sytem with bonding jumper installed. Should I drive ground rods and remove bonding jumper and leave it at that? Or leave it how it was? I always do 4 wire systems so I am at a loss.
 
I agree with jumper!!
Not sure of your specific situation, but I?m sure there is a way of bringing in a four conductor feed??
 
If this existing installation is safe --- I mean no paralleled conductors --- the AHJ may have to approve the panel ONLY replacement.
Ground rods do not apply here.

I would like to see a 4-wire system but could see allowing a SAFE 3-wire system to REMAIN.
 
jumper said:
If main panel is in attached garage, then there is no legal way for a 3 wire feed to a 120/240 sub panel that will work. Pounding in a rod or two accomplishes nothing.
Click to expand...

Does new grounding conductor need to be grouped with phase and grounded conductor?
 
jxofaltrds said:
If this existing installation is safe --- I mean no paralleled conductors --- the AHJ may have to approve the panel ONLY replacement.
Ground rods do not apply here.

I would like to see a 4-wire system but could see allowing a SAFE 3-wire system to REMAIN.
Click to expand...

what would be a safe three wire system?
 
jxofaltrds said:
If this existing installation is safe --- I mean no paralleled conductors --- the AHJ may have to approve the panel ONLY replacement.
Ground rods do not apply here.

I would like to see a 4-wire system but could see allowing a SAFE 3-wire system to REMAIN.
Click to expand...

I would think that an inspector would only have to approve a replacement panel on a 3 wire feed if:

1. The panel met code at the time it was installed.

or

2. The panel was installed under a different code other then NEC.

or

3. There was no adopted code at the time of the install.

or

4. ? Something I missed?
 
arnettda said:
Does new grounding conductor need to be grouped with phase and grounded conductor?
Click to expand...

Yes.

300.3(B) Conductors of the Same Circuit. All conductors of
the same circuit and, where used, the grounded conductor
and all equipment grounding conductors and bonding conductors
shall be contained within the same raceway, auxiliary
gutter, cable tray, cablebus assembly, trench, cable, or
cord, unless otherwise permitted in accordance with
300.3(B)(1) through (B)(4).
 
arnettda said:
what would be a safe three wire system?
Click to expand...

jumper said:
I would think that an inspector would only have to approve a replacement panel on a 3 wire feed if:

1. The panel met code at the time it was installed.

or

2. The panel was installed under a different code other then NEC.

or

3. There was no adopted code at the time of the install.

or

4. ? Something I missed?
Click to expand...

What Jumper said.

If the EGCs of the 'sub' were not tied in with ANY of the EGCs of the 'main' panel.

Do I like it? No. Would I have to approve it? I think so.
 
if you want to install an equipment ground to your new sub panel, you may have to pull the existing conductors out, and repull all of them together. is the pipe lardge enough for a egc? if they won't "budge" , disconnect everything, get a come a long strapped up somewhere with good purchase, half hitch them and pull 'em out. here's another idea, suck a string thru the existing conduit. make a small "ghost" with a small baggie, tie it to the string, suck it thru with a vac, then pull your fish thru, then your wire. it might take a while to get the string thru, but if you can seal the end of the pipe where the vac is connected really well, it should go.








there ain't many problems that a man can't fix, with $700.00 and a 30.06
 
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arnettda said:
I have a sub panel that needed to be replaced. It was feed with a three wire system. Wire will not budge to try to pull in a fouth wire. No ground rods driven for sub panel. bonding jumper installed in sub panel. How would you proced to replace panel. Main panel in attached garage feeds sub panel in basement through slab.
I replaced panel and right now it is a three wire sytem with bonding jumper installed. Should I drive ground rods and remove bonding jumper and leave it at that? Or leave it how it was? I always do 4 wire systems so I am at a loss.
Click to expand...

I don't think there is a code legal way that will work for you other than to pull a ground wire.

By any chance is the conduit metallic? that would count as an EGC.
 
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