Detached garage

[Roland Miller]

I just inspected a detached garage. The service is on a pole 5 feet away from the side of the garage. There are two ground rods for it. There is a 100 amp panel just inside. Is it OK for to use the same two ground rods for the Grounding Electrode System for the garage panel?

[Fred Warner]

I just inspected a detached garage. The service is on a pole 5 feet away from the side of the garage. There are two ground rods for it. There is a 100 amp panel just inside. Is it OK for to use the same two ground rods for the Grounding Electrode System for the garage panel?

Yes...........:)

[Roland Miller]

Would you be paralleling the neutral with the grounding electrode conductor? This was done under the 2005 NEC when you had a choice to not pull the equipment grounding conductor if there were no other metal paths. Which they didn't.. So there ended up a main bonding jumper in both panels. Do you view this as a code violation?

[Fred Warner]

Would you be paralleling the neutral with the grounding electrode conductor? This was done under the 2005 NEC when you had a choice to not pull the equipment grounding conductor if there were no other metal paths. Which they didn't.. So there ended up a main bonding jumper in both panels. Do you view this as a code violation?
You're referring to 250.32 regrounding the neutral at additional buildings or structures. The service is on a structure, namely the pole outside of the detached garage. The remote panelboard is in a building where it is permitted, under 250.32, to have its' neutral regrounded if it meets the provisions.
More than likely the neutral is grounded in the metering enclosure, too. Those conductors, as you point out, from the inside panelboard to the grounding electrodes would be grounding electrode conductors, not equipment grounding conductors. It would be very unlikely to have any substantial, measurable neutral return current on these conductors.

[Roland Miller]

I would agree that there may be minimal current. But with the main bonding jumpers in place the GEC ends up paralleled with the neutral. The GEC conductor from the pole is #6 for 200 amp service. And the one from the garage is a #8 to the other Ground Rod with a piece of #6 bonding the ground rods. Would this qualify for "any metallic path" to require the 4th EGC be pulled with the feeder conductors?? And would that solve the problem if the main bonding jumper was removed inside?

[Jeff Remas]

Depends on how the sub feed is run from the service panel/disconnect (type conduit, EGC, etc), the type of connection in the sub-feed and what code cycle the installation is under.

[Roland Miller]

Jeff--2005 NEC and it is Liquid tight flexible metal conduit. Three insulated conductors.

[Fred Warner]

I would agree that there may be minimal current. But with the main bonding jumpers in place the GEC ends up paralleled with the neutral. The GEC conductor from the pole is #6 for 200 amp service. And the one from the garage is a #8 to the other Ground Rod with a piece of #6 bonding the ground rods. Would this qualify for "any metallic path" to require the 4th EGC be pulled with the feeder conductors?? And would that solve the problem if the main bonding jumper was removed inside?

Roland, now that I have the full gist of your question, I would say the answer is NO. You will not be able to share this GES with the one required at the remote panelboard because it would violate 250.32. That's a great question and I'm sorry to have led you astray before I fully understood the question. :)

[Roland Miller]

Thanks Fred--I am the one that should apologize as it is difficult to know how much and what information each person needs in order to paint the correct picture. I would say no also. But is driving two more ground rods at the appropriate distances (and what would that be) a good solution. I would like to see an insulated equipment grounding conductor pulled with the feeder and the MBJ removed in the garage.

[Jeff Remas]

Jeff--2005 NEC and it is Liquid tight flexible metal conduit. Three insulated conductors.


Is the LFMC installed because of flexibility?
I will also assume it is listed for direct burial.

[Jeff Remas]

How many branch circuits in the detached garage?

[Roland Miller]

The LTFMC is just looped from the pole to the garage not underground. There are 9 circuits as well as a main breaker installed.

[Jeff Remas]

Then the answer is no. That pesky LFMC still has a continuous metal path too btw.

[Roland Miller]

Thanks Jeff--would a second set of ground rods be a solution??