Since you ran a grounding conductor with the feed to the subpanel, you do
not need to install a ground rod at that location.

If you feel the need to install a ground rod it should be at the main panel.
What is your current main ground?


John Grabowski
http://www.mrelectrician.tv



"the_tool_man" wrote in message
oups.com...
Hi all:

Six years ago, I built my workshop about 150ft from the house with a
100A service. I ran a four-conductor cable to the subpanel in the
shop, and kept the ground and neutral conductors isolated from each
other. I did not bond the sub-panel ground to its own ground rod,
thinking it might cause a ground loop and/or noise in the intercom
circuit bewteen the buildings. More recently, when I put in a spa with
it's own GFCI breaker, I had several people advise me to drive a
separate ground rod for it, and that I should have done the same for my
workshop. So far, I have had no issues, but I want to make sure I did
the right thing.

My searches here have yielded many debates on the need to keep the
ground and neutral bonded only in the main panel and not the subs
(which is how I did it), but nothing about the ground rod question.
Does a remote subpanel need its own ground rod or not?
Thanks in advance,
John.