Jump to content

Double Tap


Mike Lamb

Recommended Posts

I was unable to read the specs on these lugs to see if they can be double tapped. Does this scheme inside the panel help answer my question?

The schematic probably has the answer to your question, but the picture doesn't show that part of the label.

- Jim Katen, Oregon

Link to comment
Share on other sites

Is the question whether it's sometimes OK to double tap before the main service disconnect (assuming we're looking at a main disconnect)?

I thought those taps before the main were always a no-no because there would be no disconnect or overcurrent protection for whatever is downstream of the second taps. And someone might fatally assume that flipping the main disconnect had shut off everything in the house.

If I'm missing something, I'll just go back to lurking ... [;)]

Link to comment
Share on other sites

The manufacturer may allow it. Square D in this case. It would or should be printed on the side of the lug which is not easy to see. It should also tell what wire sizes that can be used. I agree that double tapping is not a good idea even if allowed.

These conductors run to a 100 amp disconnect.

Link to comment
Share on other sites

The manufacturer may allow it. Square D in this case. It would or should be printed on the side of the lug which is not easy to see. It should also tell what wire sizes that can be used. I agree that double tapping is not a good idea even if allowed.

These conductors run to a 100 amp disconnect.

If you could get the wires out of the way, the label should say.

On the other hand, I've never seen a small load center equipped with main lugs rated for more than one conductor. When they are, the hole in the lug is shaped sort of like a figure 8. See the attached pictures

Download Attachment: icon_photo.gif MultiWireLug1.JPG

190.38 KB

Download Attachment: icon_photo.gif MultiWireLug2a.JPG

216.35 KB.

- Jim Katen, Oregon

Link to comment
Share on other sites

I believe in any case where the lugs do allow 2 conductors, they still have to be the same size, no? You quite obviously have 2 different size conductors There, so it doesn't matter what the lugs are listed for, and as Jim said, doubtful they are listed for two wires anyway in that panel.

Typically anything that will allow two wires that are not of the same gauge will in some way resemble a split bolt, having two separated chambers that will adjust in size independently of the other.

Link to comment
Share on other sites

I believe in any case where the lugs do allow 2 conductors, they still have to be the same size, no? You quite obviously have 2 different size conductors There, so it doesn't matter what the lugs are listed for, and as Jim said, doubtful they are listed for two wires anyway in that panel.

Typically anything that will allow two wires that are not of the same gauge will in some way resemble a split bolt, having two separated chambers that will adjust in size independently of the other.

Actually, the lugs in the pictures that I posted are, indeed rated for two different size wires. They're rare birds though.

- Jim Katen, Oregon

Link to comment
Share on other sites

I believe in any case where the lugs do allow 2 conductors, they still have to be the same size, no? You quite obviously have 2 different size conductors There, so it doesn't matter what the lugs are listed for, and as Jim said, doubtful they are listed for two wires anyway in that panel.

Typically anything that will allow two wires that are not of the same gauge will in some way resemble a split bolt, having two separated chambers that will adjust in size independently of the other.

Actually, the lugs in the pictures that I posted are, indeed rated for two different size wires. They're rare birds though.

- Jim Katen, Oregon

How do those of us less gifted than you recognize these kinds of lugs? The notch?

Link to comment
Share on other sites

Create an account or sign in to comment

You need to be a member in order to leave a comment

Create an account

Sign up for a new account in our community. It's easy!

Register a new account

Sign in

Already have an account? Sign in here.

Sign In Now
×
×
  • Create New...