ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
ShoutChat Box
Recent Posts
Questioning the electrical norms
by gfretwell - 03/03/21 06:05 PM
Lock-down Thread
by gfretwell - 03/03/21 12:38 PM
Northern Tool Recalls Powerhorse Generators
by Admin - 02/25/21 09:49 PM
You will never guess
by gfretwell - 02/25/21 07:48 PM
New in the Gallery:
Facebook follies, bad wiring
FPE in Germany pt.2
Who's Online Now
0 registered members (), 16 guests, and 19 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Pulling through 335 deg and 500 feet? #73178 12/19/06 12:00 AM
Joined: Mar 2005
Posts: 48
R
Rich Thomas Offline OP
Member
Question: Can 2-#12,1-#12Gnd XHHW-2 stranded copper conductors be safely pulled through a 1-1/2" directly buried PVC coated GRS conduit that is 500 feet long with 335 degrees of 24-inch sweeps?

How do the experts do this??

Work Gear for Electricians and the Trades
Re: Pulling through 335 deg and 500 feet? #73179 12/19/06 05:37 AM
Joined: May 2002
Posts: 1,716
R
Roger Offline
Member
Piece of cake, the bigger question is what is the load and voltage drop?

We would either blow or vacuum a string in the conduit and then pull a 1/4" or 1/2" rope in to it for the actual pull, wire lube would be a good idea too.

Roger

Re: Pulling through 335 deg and 500 feet? #73180 12/19/06 04:08 PM
Joined: Jul 2004
Posts: 9,571
G
gfretwell Offline
Member
Since a spool of wire is typically 500' long it will be real important to know if this is 495 feet or 505. ;-)
Be sure you start with a virgin spool.


Greg Fretwell
Re: Pulling through 335 deg and 500 feet? #73181 12/19/06 04:28 PM
Joined: Jan 2004
Posts: 615
J
Jps1006 Offline
Member
I have found this http://www.electrician2.com/electa1/ductwirepull.html link handy before.

Re: Pulling through 335 deg and 500 feet? #73182 12/19/06 05:27 PM
Joined: Oct 2002
Posts: 482
Z
Zapped Offline
Member
An interesting link, but the first "rule" bullet-point conflicts with others. To say that the radius of a bend does not affect pulling tension goes against everything I have learned in over a decade of pulls. Maybe I'm imagining it? I think not.

Re: Pulling through 335 deg and 500 feet? #73183 12/19/06 05:31 PM
Joined: Nov 2005
Posts: 7
T
trublu832 Offline
Junior Member
That 1-1/2" sounds nice, my employer would of probably used 3/4" pvc.

Re: Pulling through 335 deg and 500 feet? #73184 12/19/06 05:33 PM
Joined: Jan 2003
Posts: 4,391
I
iwire Offline
Moderator
Quote
To say that the radius of a bend does not affect pulling tension goes against everything

I think that once your into large pulls with high pulling tensions (a few thousand pounds) the difference in pulling tension threw a standard 90 and large 90 is not going to be meaningfull.

The large radius 90s are used to distribute the side wall pressure over a larger area to prevent insulation damage.


Bob Badger
Construction & Maintenance Electrician
Massachusetts
Re: Pulling through 335 deg and 500 feet? #73185 12/19/06 07:48 PM
Joined: Jan 2005
Posts: 5,316
renosteinke Offline
Cat Servant
Member
I think the folks at the link meant to say "assumptions," rather than "observations." Looking at the other items in the list, this seems to be the case.

In reality, radiun DOES matter. Otherwise, we'd all be pulling through LB's. Farther down the list, they do reference the need for sweeps.

Likewise, our own experience is somewhat different on the other points. We run oversize pipe when we can. We've all seen the limits of adding a pull string for future use.
Most notably absent is any reference to the friction of different wire insulation types.

Let's not overlook the difference between 'pulling tension' and 'sidewall pressure.' Since rather small wires are involved, the use of steel sweeps for the turns is indicated in a PVC run. While the poster is running steel pipe, that is not always the case.

(Too bad the original poster didn't use 2" rather than 1 1/2". Had he done so, he could have used his pet ferret to pull those three little wires for him!)

[This message has been edited by renosteinke (edited 12-19-2006).]

Re: Pulling through 335 deg and 500 feet? #73186 12/21/06 10:41 AM
Joined: Oct 2002
Posts: 482
Z
Zapped Offline
Member
I like the ferret idea! I wonder if Greenlee has them in their catalog?


Featured:

2020 National Electrical Code
2020 National Electrical
Code (NEC)

* * * * * * *

2020 Master Electrician Exam Preparation Combos
2020 NEC Electrician
Exam Prep Combos:
Master / Journeyman

 

Member Spotlight
lil suzi
lil suzi
Midwest
Posts: 57
Joined: August 2003
Show All Member Profiles 
Top Posters(30 Days)
Popular Topics(Views)
275,604 Are you busy
209,528 Re: Forum
196,892 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.7.3