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David OKeefe
09-12-2009, 08:38 AM
OK, I have a question on this panel. A detached garage, A four wire feed was run from the service panel to this panel in the detached garage. I say four wire but only three wires were used. The grounding and grounded wires were separated except for one neutral wire on the ground bus bar, probably added later. A bonding jumper is on the bus bar, defeating the purpose of separating the two wires. A grounding wire was run to a ground rod on the exterior of the garage. OK, Because only 3 wires were used, making it a 3 wire feed then the neutral and ground wires can be bonded, correct? The feed cable to this panel is a direct burial cable, no metal conduit. If I am correct then why separate the wires in the first place and why , if they ran 4 wires out didn't they use all four?
The first four photos show the panel in the garage and the last photo is the main panel, showing the feeder cable to the garage.

Ron Bibler
09-12-2009, 08:48 AM
OK, Because only 3 wires were used, making it a 3 wire feed then the neutral and ground wires can be bonded, correct?

Correct.

The feed cable to this panel is a direct burial cable, no metal conduit. If I am correct then why separate the wires in the first place and why ,

Why ask Why ?

Best

Ron
Santa Rosa California Home Inspection - Exterminating & Thermal Imaging (http://www.santarosacahomeinspection.com)

David OKeefe
09-12-2009, 09:29 AM
Why, thank you for replying.

Jerry Peck
09-12-2009, 10:00 AM
David,

What they need to do is to attach the unused conductor at the service panel to a suitably large enough neutral terminal, making that into a four wire feeder to the garage.

Then, at the garage panel they need to attach the neutral conductor (currently unused) to the neutral terminal bar and remove the grounding wire which is attached to the neutral terminal bar, then install a grounding terminal bar to the enclosure back where it is alloted for, thus isolating the neutral and the grounds. Finally they need to remove all the grounds from the neutral terminal bar and attach them to the new grounding terminal bar.

Why did they do what they did?

At one point in time they were allowed to run a 3-wire feeder to the separate building, provided many conditions were met, AND the neutral would be insulated, not bare.

Which means that if they thought they were doing it that way, they really screwed it up.

However, being as they actually used a 4-wire feeder cable, this is no big deal (as there would be in having to run a new feeder) as they already have the conductors there, just in the wrong places. All they need to add is the new grounding terminal bar.

Someone really lucked out on their screw up, resulting in a very easy fix.

Gunnar Alquist
09-12-2009, 10:04 AM
OK, I have a question on this panel. A detached garage, A four wire feed was run from the service panel to this panel in the detached garage. I say four wire but only three wires were used. The grounding and grounded wires were separated except for one neutral wire on the ground bus bar, probably added later. A bonding jumper is on the bus bar, defeating the purpose of separating the two wires. A grounding wire was run to a ground rod on the exterior of the garage. OK, Because only 3 wires were used, making it a 3 wire feed then the neutral and ground wires can be bonded, correct? The feed cable to this panel is a direct burial cable, no metal conduit. If I am correct then why separate the wires in the first place and why , if they ran 4 wires out didn't they use all four?
The first four photos show the panel in the garage and the last photo is the main panel, showing the feeder cable to the garage.

David,

Wow, teensy photos. Hard to see much.

You can run a 3-wire to a detached building, provided that there are no other metal connections between the detached building and the building that houses the service equipment. If there is a water supply, telephone line, fence or any direct connection between the house and garage, then a separate grounding conductor and an isolated ground/neutral is required.

The problem is that we as inspectors do not always know if there are any other connections between the buildings or if there will be connections at some point in the future.

Speedy Petey
09-12-2009, 11:00 AM
You can run a 3-wire to a detached building, provided that there are no other metal connections between the detached building and the building that houses the service equipment. If there is a water supply, telephone line, fence or any direct connection between the house and garage, then a separate grounding conductor and an isolated ground/neutral is required. Thing is a 4-wire feeder was run so there is your metallic path.

If a 4-wire feeder is run the ground MUST be used, unlike was done in this case.

David OKeefe
09-12-2009, 11:03 AM
Thank you for the replies. Sorry about the photo size, I resized them to fit in my report. I did recommend that they use the forth wire and separate the neutrals and grounds. This panel had a sticker on it from the local inspector who passed it. Apparently he didn't see the missing knockouts or the nails that went through the knockout securing the panel to the studs.

Speedy Petey
09-12-2009, 12:39 PM
Ah...The good old Board. They were a great bunch of guys, but sometimes they let stuff slide that should have been called.

Rollie Meyers
09-13-2009, 08:11 AM
Thank you for the replies. Sorry about the photo size, I resized them to fit in my report. I did recommend that they use the forth wire and separate the neutrals and grounds. This panel had a sticker on it from the local inspector who passed it. Apparently he didn't see the missing knockouts or the nails that went through the knockout securing the panel to the studs.


The cable in the 2nd pic looks to be of Europeon origin, not sure but one of the conductors looks to be blue which would confirm that it is. Blue is neutral in the EU. (Current color code).If this is the case, doubt it meets any NEC requirements for use here as perm. wiring.The missing KO's are pretty sloppy at best, but the use of nails to mount a loadcenter, IMO is sloppy anyway.......

Jerry Peck
09-13-2009, 09:19 AM
The cable in the 2nd pic looks to be of Europeon origin, not sure but one of the conductors looks to be blue which would confirm that it is. Blue is neutral in the EU. (Current color code).

Interesting information - was not aware of that, thanks.

It also does not look like NM cable, looks more like flexible cord, which is not approved for permanent wiring installation either.