The Electrical Contractor Network

ECN Electrical Forum
Discussion Forums for Electricians, Inspectors and Related Professionals

Books, Tools and Test Equipment for Electrical and Construction Trades

Register Now!

Register Now!

We want your input!

Featured:
   

2017 NEC and Related
2017 NEC
Now Available!

   
Recent Posts
Would ELV branch circuits be a good idea?
by LongRunner
Today at 07:42 AM
100% breakers?
by Texas_Ranger
Today at 06:13 AM
Forum Software Upgrade coming soon...
by Trumpy
01/14/17 07:11 PM
Faricating Guards out if Lexan?
by Trumpy
01/14/17 07:09 PM
Dangerous DIY Advice
by Potseal
01/12/17 09:52 AM
New in the Gallery:
Desk-mounted "power-board"
Shout Box

Top Posters (30 Days)
HotLine1 16
gfretwell 11
sparkyinak 10
ghost307 10
Trumpy 8
Who's Online
1 registered (HotLine1), 299 Guests and 4 Spiders online.
Key: Admin, Global Mod, Mod
Topic Options
Rate This Topic
#23690 - 03/24/03 09:03 PM What do the "N" and "T" mean?
ThinkGood Offline
Member

Registered: 08/07/02
Posts: 1084
Loc: Milwaukee, WI
Regarding clamps for non-metallic cable, what do the "N" and "T" mean?


Top
Work Gear for Electricians and the Trades

Work Gear for Electricians and the Trades
Work Gear for Electricians and the Trades
Arc Flash Clothing, Gloves, KneePads, Tool Belts, Pouches, Tool Carriers, etc. etc....

#23691 - 03/24/03 09:40 PM Re: What do the "N" and "T" mean?
sparky66wv Offline
Member

Registered: 11/17/00
Posts: 2342
Loc: 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"...
_________________________
-Virgil
Residential/Commercial Inspector
5 Star Inspections
Member IAEI

Top
#23692 - 03/25/03 04:31 AM Re: What do the "N" and "T" mean?
wocolt Offline
Member

Registered: 12/06/02
Posts: 117
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

Top
#23693 - 03/25/03 04:39 AM Re: What do the "N" and "T" mean?
Redsy Offline
Member

Registered: 03/28/01
Posts: 2138
Loc: 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.

Top
#23694 - 03/25/03 08:16 AM Re: What do the "N" and "T" mean?
SvenNYC Offline
Member

Registered: 08/19/02
Posts: 1685
Loc: 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.

Top
#23695 - 03/25/03 08:32 AM Re: What do the "N" and "T" mean?
Bill Addiss Offline
Member

Registered: 10/07/00
Posts: 4196
Loc: NY, USA
Sven,

That's a good Tech Area question.

Top
#23696 - 03/25/03 06:21 PM Re: What do the "N" and "T" mean?
harold endean Offline
Member

Registered: 02/16/02
Posts: 2248
Loc: 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.

Top
#23697 - 03/25/03 08:46 PM Re: What do the "N" and "T" mean?
ThinkGood Offline
Member

Registered: 08/07/02
Posts: 1084
Loc: Milwaukee, WI
Thanks for the replies.

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

Top
#23698 - 03/25/03 09:22 PM Re: What do the "N" and "T" mean?
Bill Addiss Offline
Member

Registered: 10/07/00
Posts: 4196
Loc: NY, USA
Sven,

Look at 300.20

Top


ECN Electrical Forums - sponsored by Electrical Contractor Network - Electrical and Code Related Discussion for Electrical Contractors, Electricians, Inspectors, Instructors, Engineers and other related Professionals