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Joe Hendrix
09-30-2015, 02:25 PM
I ran across this today while installing a GFCI protected over-current "breaker". While this made finding the neutral a bit of a chore I eventually found it and then set my mind to thinking how this would have to be a wrong install of conductors. I am wanting to recommend separating the conductors to the the home owner because of the potential heat issues but am having a bit of a time finding code reference. Have you guys ever run across this before? 32155

Jerry Peck
09-30-2015, 03:43 PM
Bundling, per se, and in and of itself, in the panel is usually not an issue as the bundling length is typically less than 24".

That said, though, ... CRIMENY!

The problem I see is the twisting the conductors. As current flows through the conductors, a magnetic field builds up then collapses, and as it does, it creates impedance, and the way those are wrapped, the impedance created could ... could ... create an impedance (resistance) to the flow of the current and "choke" the current down.

Admittedly, I doubt the "choke coil" effect will 'dramatically' affect the current flow, but I suspect that 'it will' affect the current flow - in a negative manner.

Whoever was trying to be 'neat' really messed that one up.

Yes, recommend the conductors be separated.

Mark Reinmiller
09-30-2015, 05:14 PM
Looks like a tamper-proof panel to me. Who would want to work on that?

Jerry Peck
09-30-2015, 06:24 PM
Looks like a tamper-proof panel to me.

I dunno ... looks like someone already "tampered" with it to me. ;)

The more ways things are made 'idiot-proof' the more ways 'idiots' find to defeat those protections.

Like computers and those infamous ID-10-T errors ... ID10T ... :)

Lon Henderson
10-01-2015, 06:50 AM
Shor is purty, but I agree with you and Jerry.

The electrician was likely really proud of that and the extra time involved.

david shapiro
10-07-2015, 03:37 PM
I ran across this today while installing a GFCI protected over-current "breaker". While this made finding the neutral a bit of a chore I eventually found it and then set my mind to thinking how this would have to be a wrong install of conductors. I am wanting to recommend separating the conductors to the the home owner because of the potential heat issues but am having a bit of a time finding code reference. Have you guys ever run across this before? 32155

I have not. Bundling conductors in a panelboard normally very slightly impairs heat dissipation and slightly increases the difficulty of identifying which conductor is which. OTOH, it makes it a bit easier to navigate the wiring channel and even to move breakers in and out. This? I can't see the slightest reason for separating hots and returns other than ignorant cuteness.

Marshall Brown
10-08-2015, 08:31 AM
Jerry, On the choking issue you are right in a sense but the effect would be so minimal at 60 Hz as to be hard to even measure. Chokes at 60 Hz are really large even when wound on a toroid.

Technically you are not supposed to run a ground wire through a metal conduit either for much the same reason. The leading edge of a lightning stroke is nearly vertical, being composed of many, very high, frequencies, and even the little bit of metal conduit acts as a choke at those frequencies.

On the subject of "neat" panels, I encountered a nearly full 40 slot panel yesterday where each and every neutral and ground wire actually had its own lug. A first for me. State inspectors don't seem to object to the multiple conductors using one lug in Minnesota.

david shapiro
10-08-2015, 09:12 AM
State inspectors don't seem to object to the multiple conductors using one lug in Minnesota.

Are they multi-hats or straight electrical? (he asks, disturbed.) Do they have CE requirements? If it's of interest to you, I'll ask around for someone who knows of a court case where this listing violation has led to an expensive court case.

Jerry Peck
10-08-2015, 10:33 AM
Technically you are not supposed to run a ground wire through a metal conduit either for much the same reason.

Unless both ends of the metal conduit are connected to the GEC, then it is okay as it becomes a parallel path.

- - - Updated - - -


Are they multi-hats or straight electrical?

I am a multi-hat code inspector ...

david shapiro
10-08-2015, 10:39 AM
- - - Updated - - -



I am a multi-hat code inspector ...

This has what to do with Minnesota?

Jerry Peck
10-08-2015, 11:02 AM
This has what to do with Minnesota?

And what does being a multi-hat inspector have to do with doing good code inspections?

Nothing.

So my reply fit right in with your reply - neither had anything to do with what it was responding to.

Got it?

Jim Port
10-08-2015, 12:21 PM
Unless both ends of the metal conduit are connected to the GEC, then it is okay as it becomes a parallel path.


Both ends of a metallic conduit around a GEC are required to be bonded.

Jerry Peck
10-08-2015, 12:49 PM
Both ends of a metallic conduit around a GEC are required to be bonded.

Agreed and understood.

I was responding to the following, and metal conduit would not create a choke effect when both ends of the metal conduit are bonded to the GEC ... thus my presumption that Marshall was thinking of a metal conduit not bonded to the GEC at both ends.

However, I am now wondering if Marshall meant flexible metal conduit as that could create a choke effect when bonded at each end as the spike flowing through the spiral wrapped flexible metal conduit around the GEC conductor.

Marshall was not clear with what he was intending, as such, I may have made an incorrect presumption of what he was referring to.


Technically you are not supposed to run a ground wire through a metal conduit either for much the same reason.

Jerry Peck
10-08-2015, 03:27 PM
Anybody see the conductor not attached to a breaker?

Yes, it is sitting up there like a cobra ready to strike. It's not 'hot' (theoretically, anyway, as it is not attached to a breaker, but there is nothing preventing it from becoming 'hot' either.


I am at a lose as to why you would have anything done this way and have never seen bundling that excessive.

While that is, technically, "bundling', I don't concern myself too much with it (with regard to heating and bundling) as it is less than 24 inches long - the code does not address derating until the bundling - and lack of maintaining spacing, even if not "bundled" - is longer than 24 inches.

Jim Port
10-08-2015, 04:16 PM
If you unwrapped the spiral i bet it would be more than 24".

Jerry Peck
10-08-2015, 06:18 PM
If you unwrapped the spiral i bet it would be more than 24".

Very well could be, but ... I am not going to unwrap it to find out ... let the electrical contractor fix the wrapping (unwrap it) and that part of the problem is solved. :)