Feed to outbuilding..need some help
#1
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Feed to outbuilding..need some help
OK..here's what I've got. 100A sub panel in the attached garage. Its fed from the main house panel from a 100A breaker with H_H_N.
Neutral is bare. Neutral bar is bonded to ground bar. (not sure if this is right to begin with.) I want to run 60A to an outbuilding approx 90ft. Do I use 3 wire H-H-N, or 4 wire H-H-N-G?......OR do I need to rewire the sub in the garage????? Any insight is appreciated.
Neutral is bare. Neutral bar is bonded to ground bar. (not sure if this is right to begin with.) I want to run 60A to an outbuilding approx 90ft. Do I use 3 wire H-H-N, or 4 wire H-H-N-G?......OR do I need to rewire the sub in the garage????? Any insight is appreciated.
#2
The garage subpanel should have been fed with 4 conductors. Older codes used to allow 3 wire feeders to panels in detached structures, but not anymore.
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Neutral is bare.
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OK Now Im really confused. Maybe my SERVICE panel is wrong. Please bear with me. SERVICE panel has 200A feed. 2 wires to the main breaker, 1 to the neutral bar. Ground wire from outside ground rod to neutral bar. Neutral bar (on left side of panel) is connected to another bar (which I assume to be ground) via copper plate and it appears all of the above is bonded to the cabinet. Neutrals and grounds are attached to the same bars. Is this correct?
#8
Never? See Art 338 (2008) particularly B(2) and B(4)(a). The OP's installation would likely be grandfathered in.
Things changed greatly in 2011 code. See 338.10 (B)(2) exception (2011):
"In existing installations, uninsulated conductors shall be permitted as a grounded conductor in accordance with 250.32 and 250.140 where the uninsulated grounded conductor of the cable originates in service equipment and with 225.30 through 225.40."
That said, Frud's post would be the most complete/up to date installation.
Things changed greatly in 2011 code. See 338.10 (B)(2) exception (2011):
"In existing installations, uninsulated conductors shall be permitted as a grounded conductor in accordance with 250.32 and 250.140 where the uninsulated grounded conductor of the cable originates in service equipment and with 225.30 through 225.40."
That said, Frud's post would be the most complete/up to date installation.
#9
SERVICE panel has 200A feed. 2 wires to the main breaker, 1 to the neutral bar. Ground wire from outside ground rod to neutral bar. Neutral bar (on left side of panel) is connected to another bar (which I assume to be ground) via copper plate and it appears all of the above is bonded to the cabinet. Neutrals and grounds are attached to the same bars. Is this correct?
#11
Almost. Neutral is isolated and ground is bonded. The neutral may have a bonding screw or strap. That needs to be removed. The panel may not have a ground bar. You may need to buy one. There usually are tapped holes in the panel for a ground bar. Any grounds currently on the neutral bar will need to be moved to the ground bar.
#12
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As others have said, the correct answer is to run a new 4-wire feed to your garage subpanel, then run a 4-wire feed to your outbuilding. The neutral bar in each panel will be insulated from the pan while the ground bars would be bonded (screwed) to the pan.
On another topic, are you sure you want to pull the 60A feed off your 100A subpanel? Are you sure the 100A feed can handle it? It may be better/easier to just run the 60A feed back to your main panel. Of course, it's up to you - you know the loads on each.
On another topic, are you sure you want to pull the 60A feed off your 100A subpanel? Are you sure the 100A feed can handle it? It may be better/easier to just run the 60A feed back to your main panel. Of course, it's up to you - you know the loads on each.
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Ok So I was going to use AL 2-2-2-4 URD to feed the outbuilding...but was told I cant run URD inside the house. So...I have to put a junction box on the outside of the house and change wire??? really???
#14
was told I cant run URD inside the house. So...I have to put a junction box on the outside of the house and change wire??? really???