Jump to content

Garage drop


kurt

Recommended Posts

Download Attachment: icon_photo.gif KurtsGarageFeeder.jpg

159.18 KB

Here's a cleaned up picture.

If there's just one circuit, the garage doesn't need a panel. But it does need a disconnect switch - a snap switch is fine. Of course, if there's a metal path between the buildings the feeder needs a fourth wire.

Since there's no fourth wire, the garage should have it's own grounding electrode. I suppose the green wire connected to the neutral is ok. It's got to connect to it somewhere and, without a panel, it makes sense to do it there.

Those smaller wires look like THHN or THHW. Neither is supposed to be exposed to sunlight. Any conductor that's exposed to direct sunlight is supposed to be marked as being sunlight resistant.

- Jim Katen, Oregon

Link to comment
Share on other sites

It brings to mind an old 3-slot clothes dryer plug where they've joined the neutral and grounding conductors on one terminal.

A 3-wire cable to a separate building is allowed, using the neutral as the grounding conductor, only when there is only one circuit and when there are no other continuous metal pathways between the buildings such as water piping, a concrete sidewalk, metal fence, telephone line, etc. Any other metal pathways and it should have had it's own grounding electrode and one of those other paths may be used as such.

That's my story and I'm stickin' to it.

ONE TEAM - ONE FIGHT!!!

Mike

Link to comment
Share on other sites

I'm a little confused about all the talk of a fourth wire. Isn't this just a single 120-volt circuit feed? It's certainly screwed up with the exposed THNN, and who knows how it's connected at the other end, but don't we have enough conductors for that purpose.

I think Randy hit the nail on the head. Planned a real panel and "temporarily" connected 120-volt power. Needs fixin one way or the other.

Link to comment
Share on other sites

Hi Richard,

The talk of a four wire cable has to do only with the need for a sub-panel. According to Hansen, if it's only a single circuit and there are no other metal pathways between the two buildings, a 3-wire cable, using the neutral as the EGC, is fine. However, if there are any other conductive pathways, even something as small as a telephone line, then it should have it's own grounding electrode. That's why Hansen says the use of a 4-wire cable is preferred.

OT - OF!!!

M.

Link to comment
Share on other sites

Hi Mike,

OK. I do understand the requirements for a 3 and 4 wire sub-panel installation in a separate building (and even why the 4-wire is the preferred method), it was just that, looking at the wires, it looks like only a 120-volt feed.

But it does bring up another question I'm not sure about if they complete the 3-wire installation of a 240-volt panel in the garage using the existing overhead conductors. Let's assume proper grounding at the garage and no metallic path. It's normal for the utility comany to use a bare grounded conductor (with strain relief) in their 3-wire feed to a home's mast-head feeding the meter and service equipment. But...even with insulators at the strain relief, is it allowable to use a bare grounded (neutral) conductor as an overhead "feeder" to a sub-panel?

Link to comment
Share on other sites

Hi Richard,

I'm not Mike, but I do know that ALUMINUM in conduits must always be insulated. If the neutral through conduit is copper, then it is allowed.

Originally posted by Richard Moore

Hi Mike,

OK. I do understand the requirements for a 3 and 4 wire sub-panel installation in a separate building (and even why the 4-wire is the preferred method), it was just that, looking at the wires, it looks like only a 120-volt feed.

But it does bring up another question I'm not sure about if they complete the 3-wire installation of a 240-volt panel in the garage using the existing overhead conductors. Let's assume proper grounding at the garage and no metallic path. It's normal for the utility comany to use a bare grounded conductor (with strain relief) in their 3-wire feed to a home's mast-head feeding the meter and service equipment. But...even with insulators at the strain relief, is it allowable to use a bare grounded (neutral) conductor as an overhead "feeder" to a sub-panel?

Link to comment
Share on other sites

Join the conversation

You can post now and register later. If you have an account, sign in now to post with your account.

Guest
Reply to this topic...

×   Pasted as rich text.   Paste as plain text instead

  Only 75 emoji are allowed.

×   Your link has been automatically embedded.   Display as a link instead

×   Your previous content has been restored.   Clear editor

×   You cannot paste images directly. Upload or insert images from URL.

×
×
  • Create New...