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View Full Version : Correct Subpanel Scenario


RickViz
Jan 17, 2009, 08:15 AM
"#5. No ground rod is needed (and should not be installed) as long as an green equipment ground wire is pulled,(recommended and standard practice). The green wire connects to the equipment ground bar in the panel, which is bolted to the panel backbox. The neutral remains isolated on the neutral bar. Be sure the neutral bar is not connected to the panel backbox."
That is a quote from tkrussell in his reply of 9-26-06 to metagami.
I want to make sure this will apply to my situation. From what I've gathered from this forum and from "tk", is this good to go:
1) my electrical need for my detached garage workshop would be... a 12A dust collector running the same time any given woodworking machine is running, up to a 120v 20A drum sander (I'd put the dust coll. On it's own 20A breaker; the other machines on another 20A breaker-- only one would ever be on at a time); a circuit for lights (3 sets of 48" dbl flourescents and a couple small 14 watt energy saver flourescent bulbs; and possibly on this same 20A breaker circuit, a 120v window AC unit, about 10-12,000 BTU (?)

2) 60A breaker in the house's main breaker; 3#6 copper wires (2 blacks, 1 white) and 1#8 green equipment ground wire, about 65 feet to the garage, into either 1 1/4" PVC pipe 18" down, or steel or aluminum conduit 12" down; 3 20A breakers in the subpanel, isolated neutral buss...

Will this work? No ground rod necessary? Thanks

donf
Jan 17, 2009, 02:24 PM
Be Careful of the context that you are using with TK's statement.

I suspect that he stated that this is true when the subpanel and the main panel are in the same building.

Once you go to a remote building, then you are required to sink a ground Rod and connect the equipment grounding conductor.

However, the ground rod is intended to dissipate lightning not to act as an electrical ground for the circuit.

You also have to make sure the "Grounded Conductor" (White) (Neutral) is insulated from the grounding system on the subpanel.

andrewc24301
Jan 17, 2009, 03:00 PM
However, the ground rod is intended to dissipate lightning not to act as an electrical ground for the circuit.


And for some more really good information about "grounding", we blew the lid off the subject in this tread:

https://www.askmehelpdesk.com/electrical-lighting/new-fluke-300160.html

RickViz
Jan 17, 2009, 04:52 PM
Don, thank you for your response. I'm clear now about the ground rod, also on isolating the neutral buss. Is my choice of (60A) breaker and #6 wire OK, for 3 20A breakers in the subpanel? Lastly, would it be less expensive to use a GFI 60A breaker or 3 20A GFI's?
Thanks