ECN Electrical Forum - Discussion Forums for Electricians, Inspectors and Related Professionals
ECN Shout Chat
Shout Box
Recent Posts
Air Compressor feeder conductor sizing
by Potseal. 01/15/18 09:08 PM
VDE 0100 to introduce AFCIs
by LongRunner. 01/15/18 11:38 AM
Under carpet cable?
by HotLine1. 01/15/18 09:57 AM
Any New Years Resolutions?
by Bill Addiss. 01/13/18 10:21 AM
New in the Gallery:
Housebilding DIY wiring
SE cable question
Who's Online Now
0 registered members (), 15 guests, and 11 spiders.
Key: Admin, Global Mod, Mod
Previous Thread
Next Thread
Print Thread
Rate Thread
Page 1 of 2 1 2
More than 2 90's? #159599
01/08/05 06:48 PM
01/08/05 06:48 PM
E
e57  Offline OP
Member
Joined: May 2003
Posts: 2,876
S.F.,CA USA
Often, if we do not do the total install, we will get the winning bid for Electrical, which will often include some conduit for Tel/Data. So many of them have what I think is a far fetched interpitation of some of the telecom standards of pulling in conduit. i.e. The 2 90 rule... they wont pull in more than 180 degrees of bend, reguardless of fill.

So yesterday the Cablers show up, and I have to tell them the Arch would not allow extra pull boxes in some of the closed walls, and some of them have 3 90's His reply was, "We won't pull it! It damages the cable. And it's code." My reply, "What Code, I challenge you to find one." He only has 3 cat 5e cables in these 3/4" conduits, so I say, "Try some lube." His reply, "Oh, that damages the cable jackets too."

I have an idea where this comes from, an outdated TIA 568 standard (Not a Code) that was a little far fetched, and didn't differentiate fiber optic from copper cabling.

Just wondering if anyone had any thoughts on this?


Mark Heller
"Well - I oughta....." -Jackie Gleason
Study Guides for VDV / Structured Cabling Installers

Voice, Data, Video, (VDV) Fiber Optics, Communications, Low Voltage,
Fire Alarm, Electronic Security Systems Installations & Related

NTC Low Voltage Training & NICET Exam Study Guides
Low Voltage Training & NICET Exam Study Guides

Re: More than 2 90's? #159600
01/08/05 09:15 PM
01/08/05 09:15 PM
electure  Offline

Member
Joined: Dec 2000
Posts: 4,263
Fullerton, CA USA
Mark,
I'm not at all familiar with the standards, but can tell you that the 180° "dream world" predates the use of fiber optics.
I can remember hearing about it in '70.

Re: More than 2 90's? #159601
01/08/05 09:24 PM
01/08/05 09:24 PM
E
e57  Offline OP
Member
Joined: May 2003
Posts: 2,876
S.F.,CA USA
Here I was thinking it was new.... I was born in '70! [Linked Image]


Mark Heller
"Well - I oughta....." -Jackie Gleason
Re: More than 2 90's? #159602
01/10/05 11:31 PM
01/10/05 11:31 PM
G
golf junkie  Offline
Member
Joined: Apr 2001
Posts: 507
York, NE
I have seen this often in specs. but I've never seen anyone get bent about it.

Re: More than 2 90's? #159603
01/11/05 03:43 PM
01/11/05 03:43 PM
D
dstanford  Offline
Member
Joined: Dec 2004
Posts: 23
Asheville NC USA
well i would rather not have alot of J-Boxes
in my big backbone and interduct pulls
you can always put another wrap on the tugger and use Lots of Lube.
sounds like pure lazyness to me

Re: More than 2 90's? #159604
01/11/05 09:34 PM
01/11/05 09:34 PM
G
golf junkie  Offline
Member
Joined: Apr 2001
Posts: 507
York, NE
I would be interested to hear if anyone has actually ever damaged a cat 5 cable due to excess pull strain and under what conditions that occurred?

Re: More than 2 90's? #159605
01/11/05 10:07 PM
01/11/05 10:07 PM
S
SolarPowered  Offline
Member
Joined: Jul 2004
Posts: 625
Palo Alto, CA, USA
Would you even know if you'd damaged it? You'd probably have to ping it out with a TDR to find out. With the error-recovery mechanisms built into comm protocols, the user likely isn't going to realize what's going on, either--he'll just have slower network performance than he would have had if there was no damage.

Re: More than 2 90's? #159606
01/11/05 11:40 PM
01/11/05 11:40 PM
E
e57  Offline OP
Member
Joined: May 2003
Posts: 2,876
S.F.,CA USA
Graphic TDR it would still be realy difficult to tell I think, unless you printed out each pair before you pulled as a refferance. I'm sure someone with too much time on thier hands can cut to length test and install to check it again, like in some testing lab. However I can say that most Certification meters will test exactly the same before and after. (With the same termination.)

With pulling tension of 25lbs max, you could bundle a dozen or so and swing like Tarzan..... Kidding [Linked Image]


Mark Heller
"Well - I oughta....." -Jackie Gleason
Re: More than 2 90's? #159607
01/12/05 10:24 AM
01/12/05 10:24 AM
Radar  Offline
Member
Joined: Apr 2004
Posts: 349
Los Angeles, CA
Here at the large public agency I work for in the Los Angeles area, when we award contracts for the installation of conduit to be used for data lines, we specify no more than 2-90's between openings. Nothing to do with code. Our IT techs who pull in the cabling later (fiber or cat-5) don't care if the openings are pull boxes or condulets, they just want easy pulling. Personally I don't think they have a tugger available, and wouldn't know how to use one (they aren't wiremen).

Radar


There are 10 types of people. Those who know binary, and those who don't.
Re: More than 2 90's? #159608
01/12/05 11:59 AM
01/12/05 11:59 AM
H
hbiss  Offline
Member
Joined: Dec 2003
Posts: 886
Hawthorne, NY USA
Don't think you would want to use a tugger with those cables.

Personally I think the "2 90" requirement is silly. I can't imagine how you could comply in many situations. No reason that you can't upsize the conduit and use a lubricant if necessary. Never heard of a lubricant damaging a cable by the way.

Maybe you need to rethink allowing IT techs with no experience doing this type of work.

-Hal

Page 1 of 2 1 2

Featured:

2017 Master Electrician Exam Preparation Combos
2017 NEC Electrician
Exam Prep Combos:
Master / Journeyman

 

Member Spotlight
Posts: 165
Joined: March 2007
Show All Member Profiles 
Top Posters(30 Days)
sparky 23
Admin 19
Potseal 13
Popular Topics(Views)
243,511 Are you busy
180,298 Re: Forum
170,800 Need opinion
Powered by UBB.threads™ PHP Forum Software 7.6.1
(Release build 20180101)
Page Time: 0.026s Queries: 15 (0.004s) Memory: 1.0279 MB (Peak: 1.2029 MB) Zlib enabled. Server Time: 2018-01-16 17:33:40 UTC