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!


2017 NEC and Related
2017 NEC
Now Available!

Recent Posts
International Wire Colour Codes
by Texas_Ranger
Today at 08:24 AM
Son of Sparky
by HotLine1
10/20/16 07:43 PM
Speaking of Plugmold ...
by gfretwell
10/17/16 02:37 PM
Broken battery charger? Check for cobwebs!
by gfretwell
10/17/16 02:30 PM
230 or 345 kV transmission lines?
by annemarie1
10/12/16 01:23 PM
New in the Gallery:
12.5A through 0.75mm flex (just out of curiosity)
Shout Box

Top Posters (30 Days)
gfretwell 11
renosteinke 6
HotLine1 6
ghost307 5
Potseal 4
Who's Online
0 registered (), 198 Guests and 4 Spiders online.
Key: Admin, Global Mod, Mod
Topic Options
Rate This Topic
#23907 - 03/30/03 09:28 AM THW wire
CTwireman Offline

Registered: 02/07/02
Posts: 839
Loc: Connecticut, USA
I have 2 old spools of THW wire. Is is permissible to use this anymore?

I am thinking about using it feed a tool shed through 3/4 pvc.

If not, I will be taking a run to the scrap yard.


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....

#23908 - 03/30/03 09:35 AM Re: THW wire
iwire Offline

Registered: 01/05/03
Posts: 4343
Loc: North Attleboro, MA USA
It is listed in 310.13 as OK for dry and wet locations, there is no reason not to use it.

Remember if you run out more than 1 circuit you will need a ground rod out there.
Bob Badger
Construction & Maintenance Electrician

#23909 - 03/30/03 09:41 AM Re: THW wire
CTwireman Offline

Registered: 02/07/02
Posts: 839
Loc: Connecticut, USA
Thanks Bob. It's for a single circuit, so I don't have to worry about the ground rod.

#23910 - 03/30/03 01:41 PM Re: THW wire
Ron Offline

Registered: 03/13/02
Posts: 577
Loc: White Plains, NY
THW is a great conductor as its insulation is more durable (thicker) during a pull through conduit. It is rated for wet environment, as underground installation must be considered.

[This message has been edited by Ron (edited 03-30-2003).]

#23911 - 03/30/03 01:43 PM Re: THW wire
NJwirenut Offline

Registered: 09/15/01
Posts: 816
Loc: Bergen County, NJ
Doesn't "THW" signify THermoplastic, Wet location?

#23912 - 03/30/03 04:13 PM Re: THW wire
Bjarney Offline

Registered: 04/10/02
Posts: 2561
Loc: West-Southern Inner-Northeast ...
The H in THW probably designates it as 75°C insulation, versus TW being 60°C. In a number of areas, it was the default industrial building wire before THWN/THHN was popular. Earlier, THW aced out RHW with improved ease of handling.

[No hepcat electrician would use solid TW if he could get stranded THW.] At one time, TW was available in solid up to 6AWG.

[This message has been edited by Bjarney (edited 03-30-2003).]

#23913 - 03/31/03 09:25 AM Re: THW wire
kale Offline

Registered: 11/08/02
Posts: 168
"THW----PVC insulated building wire. Flame-retardant, moisture and heat-resistant, 75deg C. Dry and wet locations."

From Essex Wire&Cable Reference Guide 1997.

[This message has been edited by kale (edited 03-31-2003).]


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