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silvestre
10-01-2003, 06:34 AM
Hello!

Please anyone could help me regarding my query below.

I have a project that I need a justification regarding the separation of power and signal cable. The voltage is 24VAC for power. Please let me know any article in NEC or other reference that may help.

Appreciate your soonest reply.

Cheers
Silvestre

tom baker
10-01-2003, 08:55 AM
See 90.3
See 300.3(C)I think this is the right section.
and 725.54
You have to maintain seperation even if insulated for same voltage, a few exceptions, it depends on class of 24 V circuit. Article 725 is the appropiate article.

websparky
10-01-2003, 07:30 PM
Depends also on what type of system we are talking about and if it is a power limited supply.

More info would be helpful!

silvestre
10-01-2003, 09:00 PM
Appreciate your reply!

Thanks a lot! I will look on this article and will get back to you later.

By the way, the system I am talking here is CCTV and this is a separation of power and RG59 and LAN cable.

Thanks and best regards,
Silvestre

hbiss
10-01-2003, 09:52 PM
There isn't any requirement that these cables be separated per the NEC and they are quite commonly pulled together even through raceway.

jrdsg
10-03-2003, 12:01 AM
i'm not sure i understand the question, but...

no seperation is necessary between class 2 pl low voltage and video/lan/tel cable. in fact we regularly run both signal and 24V AC or 12V DC power up the same CAT5 or CAT3 wiring. Some CCTV installations run 12VDC up the coax to the cameras.

of course siamesed installations of this kind require special termination equipment to prevent cross-talk and other interference.

co-locating signal and 120V or higher voltage cable requires appropriate separations. some kinds of low voltage wiring is also unusually noisy. alarm system combus wire, rs485 or rs422 wire, and 70v paging wiring can be especially problematic. attention needs to be paid to proper shielding of any splice points and to the use of shielded wire with a drain where noise may be a problem.

silvestre
10-03-2003, 03:21 AM
Thanks to all who replied to my query!

I am just worried because I worked for high voltage before ( 220 - up ) then I got a new job which is different, a digital security.

Appreciate all your informative reply.

Cheers

silvestre