# I saw this at a factory I worked in today.



## NC Plc (Mar 24, 2014)

In this piece of equipment, there is the power feeding into a three phase 100A breaker. From this breaker each phase has three eight gauge wires feeding a daisy chain that feeds into I am guessing 10-12 16 amp breakers that are also three phase. From the breakers, 12 gauge wire feeds to the various motors.

Is that NEC legal? I didn't think to ask my boss, it just seemed off to me. If it matters the machine came from somewhere in Europe.


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## Awg-Dawg (Jan 23, 2007)

NC EET said:


> In this piece of equipment, there is the power feeding into a three phase 100A breaker. From this breaker each phase has three eight gauge wires feeding a daisy chain that feeds into I am guessing 10-12 16 amp breakers that are also three phase. From the breakers, 12 gauge wire feeds to the various motors.
> .


 That's pretty typical.



NC EET said:


> Is that NEC legal? I didn't think to ask my boss, it just seemed off to me. If it matters the machine came from somewhere in Europe.


 It doesn't fall under the NEC.


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## NC Plc (Mar 24, 2014)

Awg-Dawg said:


> It doesn't fall under the NEC.


Could you elaborate on that a bit?


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## ponyboy (Nov 18, 2012)

NC EET said:


> Could you elaborate on that a bit?


It could be part of a listed industrial control cabinet


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## Big John (May 23, 2010)

It works because it's a bunch of tap connections, just like the ones allowed in the NEC. The biggest concern is making sure the multiple conductors are secure in each breaker terminal. But how a piece of apparatus works is outside the scope of the NEC anyway, and as long as it had a recognized ETL stamp on it somewhere, I'd leave it be.


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## NC Plc (Mar 24, 2014)

Big John said:


> It works because it's a bunch of tap connections, just like the ones allowed in the NEC. The biggest concern is making sure the multiple conductors are secure in each breaker terminal. But how a piece of apparatus works is outside the scope of the NEC anyway, and as long as it had a recognized ETL stamp on it somewhere, I'd leave it be.


Thanks man.


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## JRaef (Mar 23, 2009)

Big John said:


> It works because it's a bunch of tap connections, just like the ones allowed in the NEC. The biggest concern is making sure the multiple conductors are secure in each breaker terminal. But how a piece of apparatus works is outside the scope of the NEC anyway, and as long as it had a recognized ETL stamp on it somewhere, I'd leave it be.


But it also depends on HOW they accomplished it. Most standard breaker terminals on a 100A MCCB are rated for one, maybe 2 wires of the same size in each connection. Any more than 2 and it must have a non-standard terminal lug, either a stud, to which ring crimp lugs are attached to each conductor, or something like this "distribution lug" on the breaker;










If they just jammed 3 conductors into a single hole mechanical compression lug, I am unaware of any that are UL listed for that. So even if the panel has an NRTL label on it, if an AHJ sees a flagrant violation like that, he may still reject it.


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## 360max (Jun 10, 2011)

JRaef said:


> But it also depends on HOW they accomplished it. Most standard breaker terminals on a 100A MCCB are rated for one, maybe 2 wires of the same size in each connection. Any more than 2 and it must have a non-standard terminal lug, either a stud, to which ring crimp lugs are attached to each conductor, or something like this "distribution lug" on the breaker;
> 
> 
> 
> ...


if its a UL listed piece of equipment, which it probable is, the local AHJ authority ends at the supply connection.


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## IMM_Doctor (Mar 24, 2009)

*Scope 90.2*



NC EET said:


> Could you elaborate on that a bit?


NFPA 70 National Electrical Code does not specifically look at the engineered practices within an industrial machine, but only the conductors supplying that machine, and the NAMEPLATE information required on that machine.

See NFPA 70 article 90.2 SCOPE


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## IMM_Doctor (Mar 24, 2009)

*?*

No that I referenced 90.2 Scope...
As to what NFPA 70 NEC applies to...

WTF is 90.2 (a)(2) Yards, Lots...?

What is a Yard or a Lot?

If you look at article 100 Definitions there is no Yards or Lots

Does this mean YARD Sales, and big LOTS?


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