Ground Wires Under One Terminal

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cubman

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A piece of machinery was delivered to the job site with 11 # 14 ground wires under one bolt in its control panel. We told the manufacturer a ground bar would have to be installed. He claims this practice is perfectly legal. The inspector did not agree and failed the install. The manufacturer requested the code section in which he was in violation. The inspector said 110.14A. There has got to be a more detailed explanation in the code than this reference. I have been looking and have had no luck.

Could use a little help

CUBMAN
 
The manufacturers of equipment do not have to comply with the NEC. The inspector has gone into an area where he has no jurisdiction. If the equipment is listed end of story.
 
I agree with Trevor, this is a very misguided inspector. He would have a heart attack if he looked inside HVAC equipment or refrigeration control panels.
 
If this is listed equipment then its covered under the listing and may be allowed. Find out what the listing is, such as UL508A. I have the UL508A standard at work and can check, however, UL508A pretty much follows the NEC and I would be surprised if what the inspector cited as a violation is allowed.
If its not listed and not covered under a NFPA 79 application then the inspector may have some grounds for rejection.
 
cubman said:
A piece of machinery was delivered to the job site with 11 # 14 ground wires under one bolt in its control panel.
Click to expand...

If this were a split-bolt type with a 1/4-20 mount I still would not see a problem as most only provide a wire size range, but not quanity....
 
split-bolt type connectors

split-bolt type connectors

e57 said:
If this were a split-bolt type with a 1/4-20 mount I still would not see a problem as most only provide a wire size range, but not quanity....
Click to expand...

e57,
I have tried with no avail to research this thru the manufacturers sites.
Perhaps one of our more learned members can enlighten me, but I've been told in one of the seminars I attended that "split bolt" type connectors are actually only listed for one line with 1 tap conductor.
Although used with multiple "taps", I am led to beleiev that is a listing violation.
Anyone ??
 
augie47 said:
e57,
I have tried with no avail to research this thru the manufacturers sites.
Perhaps one of our more learned members can enlighten me, but I've been told in one of the seminars I attended that "split bolt" type connectors are actually only listed for one line with 1 tap conductor.
Although used with multiple "taps", I am led to beleiev that is a listing violation.
Anyone ??
Click to expand...

Both Blackburn and Burndy talk about run size and tap size when sizing Kerneys. They don't explicitly exclude multiple wires. I'm also led to believe that you're only allowed two wires in a split-bolt. I will also say that I've put more than that in a Kerney on more than one occasion. I trust this type of connection more than I do a Big Blue or Grey.

For quality work, I will install a ground bar in larger J-boxes. Much cleaner looking. To get the equipment up and running during an emergency service call.....Big Blue it is.
 
The key is the equipment. Is this a one-off custom item that some "manufacturer" built from listed components pieced together and is not listed as a single unit, or is this a listed unit that has been tested by a lab?
 
A method that I have seen on commercially build hardware, as well as used on hardware that we've built in the lab, is to have multiple conductors, each terminated with a crimp on ring lug, stacked on a single stud terminal.

I don't see a problem with this sort of termination if:
a) the proper sized ring lugs are used for the stud and the conductor
b) the conductors do not interfere with each other (eg. the conductors aren't stressed by being squeezed against each other when the stud is tightened.
c) appropriate tension can be maintained on the stack of rings.

I don't know about NEC permissibility, arguably the conductors are not terminated on the screws, but instead are terminated in the lugs, and then the screw is mechanically mounting the ring portion of the lug. However as infinity notes, the NEC may not apply since this is part of a piece of equipment.

-Jon
 
very, very common. no issue IMO.

winnie said:
A method that I have seen on commercially build hardware, as well as used on hardware that we've built in the lab, is to have multiple conductors, each terminated with a crimp on ring lug, stacked on a single stud terminal.

I don't see a problem with this sort of termination if:
a) the proper sized ring lugs are used for the stud and the conductor
b) the conductors do not interfere with each other (eg. the conductors aren't stressed by being squeezed against each other when the stud is tightened.
c) appropriate tension can be maintained on the stack of rings.

I don't know about NEC permissibility, arguably the conductors are not terminated on the screws, but instead are terminated in the lugs, and then the screw is mechanically mounting the ring portion of the lug. However as infinity notes, the NEC may not apply since this is part of a piece of equipment.

-Jon
Click to expand...
 
No UL or any other stickers in or on the unit

No UL or any other stickers in or on the unit

60 of these conveyor units showed up on site. Of the 32 installed not one works properly. Photo eyes operating wrong motors, a complete train wreck. The manufacturer must have subbed the work out to some foreign country without UL inspections.
Is there a better code reference for the number of wires under a bolt or can i install a 6' bolt rod in a cabinet and attach ring terminals to it until I reach a million grounds
 
cubman said:
60 of these conveyor units showed up on site. Of the 32 installed not one works properly. Photo eyes operating wrong motors, a complete train wreck. The manufacturer must have subbed the work out to some foreign country without UL inspections.
Is there a better code reference for the number of wires under a bolt or can i install a 6' bolt rod in a cabinet and attach ring terminals to it until I reach a million grounds
Click to expand...
First off UL does not inspect control panels. They list them.

Secondly, UL does not verify that either the design or installation of a listed control panel is correct.

As far as I can tell, you could indeed install a 6 foot long bolt and put as many ground wires under it with ring tongue terminals as you want and not be in violation of UL listing standards.

people keep telling you it is NOT A CODE ISSUE. you won't find anything about the minimum standards required of a UL listed control panel in the NEC.

In fact, AFAIK, there is no prohibition in the NEC to do this as part of an installation either. The reason might be because there is nothing wrong with it. As long as the connections are solid, why would anyone care just how the connections are made?
 
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I did not wish to hijack this thread, so I started another entiltled "split bolts" however, since I broough it up here I thought I wouold at least post T&B's reply to my inquiry."All testing and listing for UL requirements is done with only 2 conductors - one line and one tap.
It is possible other combinations may pass the requirements but we have no testing to verify this performance."


Byron Raines
Manager - Technical Services
Thomas & Betts
 
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