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#23690 - 03/25/03 01:03 AM What do the "N" and "T" mean?  
ThinkGood  Offline
Member
Joined: Aug 2002
Posts: 1,081
Milwaukee, WI
Regarding clamps for non-metallic cable, what do the "N" and "T" mean?

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#23691 - 03/25/03 01:40 AM Re: What do the "N" and "T" mean?  
sparky66wv  Offline
Member
Joined: Nov 2000
Posts: 2,236
West Virginia
The N stands for Non-metallic Cable

The T stands for "tubing" and is a reference to Loom tubing.

These clamps are listed for both NM cable and Loom.

Hence the name "Loom Clamps"...


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#23692 - 03/25/03 08:31 AM Re: What do the "N" and "T" mean?  
wocolt  Offline
Member
Joined: Dec 2002
Posts: 110
T stands for tube or loam(???), are those holes big enough to get two K and T wires in one hole with the tube.
As you know you cannot separate the wires ie one per hole because of inductive heating.
just my 2 cents.

WOC


#23693 - 03/25/03 08:39 AM Re: What do the "N" and "T" mean?  
Redsy  Offline
Member
Joined: Mar 2001
Posts: 2,056
Bucks County PA
K&T wiring normally is separated throughout the system and it enters boxes via 2 separate holes. I'm not sure that there is enough separation of the wires in small wall cases to cause inductive heating problems, which is also of course related to the amount of current flowing.


#23694 - 03/25/03 12:16 PM Re: What do the "N" and "T" mean?  
SvenNYC  Offline
Member
Joined: Aug 2002
Posts: 1,691
New York City
Quote
As you know you cannot separate the wires ie one per hole because of inductive heating.


Could you elaborate on this? I don't understand. How can separating wires cause heating?

I thought you had to derate when you bunched up wires because that is when they can potentially start heating up. [Linked Image]


#23695 - 03/25/03 12:32 PM Re: What do the "N" and "T" mean?  
Bill Addiss  Offline
Member
Joined: Oct 2000
Posts: 3,878
NY, USA
Sven,

That's a good Tech Area question.


#23696 - 03/25/03 10:21 PM Re: What do the "N" and "T" mean?  
harold endean  Offline
Member
Joined: Feb 2002
Posts: 2,233
Boonton, NJ
You are suppose to cut the notch out between the two holes in order to reduce the magnetic build up between the 2-K&T wires. This way each K&T wire enter the box through it's own space.


#23697 - 03/26/03 12:46 AM Re: What do the "N" and "T" mean?  
ThinkGood  Offline
Member
Joined: Aug 2002
Posts: 1,081
Milwaukee, WI
Thanks for the replies.

...The things one can learn on this board!!!!


#23698 - 03/26/03 01:22 AM Re: What do the "N" and "T" mean?  
Bill Addiss  Offline
Member
Joined: Oct 2000
Posts: 3,878
NY, USA
Sven,

Look at 300.20



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