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

Topic Options
Rate This Topic
#180842 - 09/12/08 04:42 PM Egress lighting remote head wiring method
Redsy Offline
Member
Registered: 03/28/01
Posts: 2056
Loc: Bucks County PA
I have seen thermostat cable used to feed remote emergency lights from remote capable emergency lighting units.
Although the batteries only provide 6 volts, it seems that having t-stat cable in the same enclosure as 120 volts would be a violation, unless the t-stat cable is rated for 120 volts per 300.3(C)(1).
I haven't been able to determine the voltage rating of the t-stat cable(no marking).

Opinions, please?

Top
Work Gear for Electricians and the Trades
#180847 - 09/12/08 07:49 PM Re: Egress lighting remote head wiring method [Re: Redsy]
frenchelectrican Offline
Member
Registered: 02/06/03
Posts: 939
Loc: Wi/ Paris France { France for ...
IMO.,,

You allready ran into few serious issue with this.,,

The thermosat cable are typically 18 or 20 gauge wire size and most emergecy lights { AKA bug eyes or frog eyes } are very senstive with voltage drop.

second matter is majotry of thermostat wire are Class two current limit type.

not too often I will see the thermostat wire insulating material will be the same as building wire rating normally they are 300 v or less unless written something else on the cable or conductor.

And the local code may have additonal infomation realted to this and please check with them for latest info.

Merci,Marc
_________________________
Pas de problme,il marche n'est-ce pas?"(No problem, it works doesn't it?)

Top
#180857 - 09/13/08 07:39 AM Re: Egress lighting remote head wiring method [Re: frenchelectrican]
HotLine1 Offline


Member
Registered: 04/03/02
Posts: 6778
Loc: Brick, NJ USA
Redsy:
Usual remote wiring methods are 'Chapter 3 methods', as the rest of the job, with the same cable/conduit. VD is a definite issue. The instructions that come with the item should specify/suggest/reccomend the ga of conductor required, based on the circuit length.

I see you said 'capable' in your OP. A few guys try to tap off of the LED exit units! 90 min test? Forget it.

Also, 700.16, second paragraph ('05 NEC) is enforced.

Years back, two country clubs were big into remote em ltg, and 'did not want the battery box visable to the members. Some runs to the heads were 150'; (# 6 & #8)



_________________________
John
Top
#180865 - 09/13/08 10:29 AM Re: Egress lighting remote head wiring method [Re: Redsy]
Redsy Offline
Member
Registered: 03/28/01
Posts: 2056
Loc: Bucks County PA
Thanks, Guys.

I'm talking specifically about an exterior remote head driven by a remote capable combo unit on the wall immediatley inside. Voltage drop would not be an issue at 3-4 ft.

I saw 150-volt t-stat wire in Graingers.

If the t-stat wire is rated for the higher voltage in the combo unit, I don't know if I can find a code-related issue.
A possible issue may be a non-metallic wiring method above a drop ceiling in a commercial bldg., but it is Romex that is specifically prohibited in that case.

Note:
I am not advocating this practice. I have debated it with another contractor, and am asking for opinions.
Top
#180872 - 09/14/08 07:35 AM Re: Egress lighting remote head wiring method [Re: Redsy]
HotLine1 Offline


Member
Registered: 04/03/02
Posts: 6778
Loc: Brick, NJ USA
Redsy:
For debate reasons, I throw into this thread...Article 720 (2005 NEC):
720.1 Under 50 v, AC/DC
720.2 N/A, as it is egress lighting, not any referenced.
720.3 N/A
720.4 Conductor size minimum (#12)

Based on this, IMHO, you need #12 t'stat wire, rated 150 volts or higher from your OP.
Based on that...why bother?

(IF 720 is referenced by the local AHJ!)

Sunday morning thoughts...


_________________________
John
Top
#180873 - 09/14/08 08:49 AM Re: Egress lighting remote head wiring method [Re: Redsy]
Redsy Offline
Member
Registered: 03/28/01
Posts: 2056
Loc: Bucks County PA
John,

Thank you much!

Top

Member Spotlight
Member Since: 08/22/05
Posts: 44
New in the Gallery:
SE cable question
Featured:

2017 NEC and Related
2017 NEC
Now Available!

Shout Box


Who's Online
0 registered (), 30 Guests and 8 Spiders online.
Key: Admin, Global Mod, Mod
 
New in the Gallery:
SE cable question
 
Top Posters (30 Days)
Admin 47
HotLine1 43
gfretwell 19
Ruben Rocha 12
Trumpy 9
 
Newest Members
Scotto, Freecrowder, clee512, Jdscott2005, FAIZAN

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