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Jim McClendon
05-10-2007, 03:41 AM
Has anyone seen the grounds twisted together like this and is it ok? Why do it?

Jerry Peck
05-10-2007, 05:27 AM
Has anyone seen the grounds twisted together like this and is it ok? Why do it?


Yes, many times, and it is still and always wrong.

Why? To save putting them into their own holes? It took a lot longer to twist them together than it would have to just have put each (or even two if allowed) into their own terminals.

'Hey, Bubba, lookee here, I just made me a stranded wire, looks neat,huh?'

Jim McClendon
05-10-2007, 05:40 AM
Thanks Jerry.

Jim McClendon
05-20-2007, 11:57 AM
Why is it still and always wrong? I cant find any information about it.

Bob Mayer
05-20-2007, 06:46 PM
Why is it still and always wrong? I cant find any information about it.

I cannot find where the NEC prohibits this, but I would guess that the panelboard (or terminal bar) manufacturer prohibits it. Remember everything has to be installed in conformace the NEC and with the manufacturer's instructions. See this post http://www.inspectionnews.net/home_inspection/electrical-systems-home-inspection-commercial-inspection/422-multiple-neutrals-under-same-lug.html#post1925,
the whole thread is useful.

- BOB

Scott Patterson
05-20-2007, 07:01 PM
It has to do with the conductors making the proper contact. If they are all bunched up together, some will be loose and may not make proper contact. Also the bending and twisting will weaken the wire to a point that they could break. I believe it is also on the panels schematics and it can be found in the codes.

James Duffin
05-20-2007, 07:45 PM
It is wrong because the terminal is not rated for the number of wires plus if you ever have to service a circuit wrapped up in the twisted mess it would involve unwrapping the whole bundle. I would write it up for the reason I stated but it would never be addressed I feel sure.

Mike Huppi
05-20-2007, 08:41 PM
Yea but it looks cool dont ya think

Thom Walker
05-20-2007, 09:22 PM
Jim,
Is this helpful? Ignore the title. Read the whole thing for rationale.

Jim McClendon
05-21-2007, 06:28 AM
Thanks for the replies. The terminal is rated for 3 wires. The licensed electrician said they twisted the wires for better continuity. I was wondering... your thoughts?

Bob Mayer
05-21-2007, 08:15 AM
Thanks for the replies. The terminal is rated for 3 wires. The licensed electrician said they twisted the wires for better continuity. I was wondering... your thoughts?

I count 20 circuits. It looks as if there are two single grounding conductors at the bottom of the grounding bar. This leaves 18 grounding conductors in four bundles, more than the three conductors per bundle for which you say the terminals in the ground bar are rated. If it violates the manufacturer's instructions, it fails the inspection and should be repaired. Whether it has "better continuity" or not is irrelevant. There is a saying in the Free Software arena: "With many eyes, all bugs are shallow." The NEC has been subject to many eyes for over 100 years. Deviations from it in this panel are not subject to "many eyes," but are subject to the boost that Murphy's Law gives to unintended side effects. I do not mean to go on and on (I do not think that I do :) ), but it bothers me when someone, especially a licensed someone, say that he or she knows better than the code or the manufacturer's requirements.


It is wrong because the terminal is not rated for the number of wires plus if you ever have to service a circuit wrapped up in the twisted mess it would involve unwrapping the whole bundle. I would write it up for the reason I stated but it would never be addressed I feel sure.

I have worked on panelboards with long lengths of twisted grounding conductors similar to those in the photograph and James is right. The only safety aspect of such a situation is that I shut off the main breaker for a job for which I might not otherwise.;) Untwisting all the conductors is a pain, and after they are untwisted they are a real mess, I spend more time trying to straighten them out than I did untwisting them.

- BOB

Jim McClendon
05-21-2007, 02:01 PM
Thanks Bob, I appreciate the detail.

Jerry Peck
05-21-2007, 05:19 PM
Thanks for the replies. The terminal is rated for 3 wires. The licensed electrician said they twisted the wires for better continuity. I was wondering... your thoughts?

DO NOT twist them.

They will have a better connection laying on each other than being twisted (unless you can duplicate the twist and laying together of the machine done stranded wire, but I doubt you will find '3 strand stranded wire', so that's pretty much out of the question.