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pgbhp
Dec 3, 2007, 11:29 PM
Have metal pole building about 80 feet from house. I intend to run 100 amp from house panel to sub panel in shop. Originally purchased a cutler hammer mail lug panel CH8L125SP for this use (on sale) but think I would rather have a 100 amp main breaker panel so as to use as single disconnect in the shop, still with 100 amp protection in the house (feed) panel. I have been told that I must have a ground rod (s) at the shop with the metal shop of course bonded to the ground. Do I still need to run a ground wire along with the hot wires and neutral between the house panel and the sub panel? If I do not run this ground, do I then bond the neutral and ground bars inside the sub panel since I will have the ground rod(s) in the earth next to the shop. Thanks for any advice.

Washington1
Dec 4, 2007, 12:43 AM
The NEC gives you an option of running 3 or 4 conductors if there are no continuous metallic paths between both structures . Regardless-in your case-you will have to install two ground rods. Note: Some jurisdictions--such as ours--require four conductors. I highly recommend four conductors! The 2008 will require four. If you do not have to run 4 conductors, then the grounded conductor will have to be connected to the grounding electrodes at your separate structure.

Washington1
Dec 4, 2007, 12:48 AM
PS: You will need the a main in your case

tkrussell
Dec 4, 2007, 03:39 AM
Run 4 wire feeder. The 3 wire method will be removed from the next code edition, as mentioned by Washington. The 4 wire method is much better, I agree.

Either still needs a ground rod at the separate building, including grounding the metal building.

pgbhp
Dec 4, 2007, 01:48 PM
Thanks Washington1 and TKRussell. Appreciate the quick response. I will go with the 4 wires.