running fire alarm cables in the same conduit with Data

[skip555]

talking to a customer today who is having a building built and she said they want to run the fire alarm cabling in the same condiut as the data cable from the panel up into the ceiling

I'm not to happy with it but I really dont see it causing a problem .

am I correct or should we tell them to get their own path up ?

 

[franklin97355]

You should check with the building codes department in your jurisdiction as they will be the people that will say if this is legal where you are or not. If they have no objections and your state codes don't specify then check the NEC to see what they specify then make your decision

 

[hbiss]

Apparently this is PLFA or power limited fire alarm wiring. The wiring is run exposed like your cat 5 throughout the building. I see no problem, NEC or otherwise, with putting this in the same conduit sleeve as the data wiring even if it were longer than a few feet.

-Hal

 

[skip555]

seems to me the alrm wire is passive most of the time so I didnt really expect a problem but there are some real knowledgable peaple here so I figured if there where any issues somebody here would know .

 

[franklin97355]

I see no problems doing it other than violating the local building codes and having to rip it all out and doing it to code.

 

[jeffbouldin]

I install fire alarms, security, access, cctv, and some networking. As much as possible always seperate(sp?) different types of wire. Many new fire alarm systems are addressable, they run data over the wire instead of voltage. This has been known to cause problems on networks. Alot of fire alarm systems recommend keeping the horn/strobe circuit run seperate from the addressable loop.

I believe it is written in the National Fire Code to keep fire rated cable seperate. I'll ask our codes expert tommorow.

Who is installing the fire alarm? Most states require a special liscence(again sp?) to do this. You have to be very careful, we have a problem with unqualified companies or electricians doing fire alarms and doing a dangerously poor job. Most times this is discovered after we are called in because it has had nothing but problems that could have been prevented by a proper install. Very expensive to fix.

 

[daronwilson]

Personally, I would put a separate conduit in for the riser for fire alarm.

Some good points have been made though, assuming it is power limited, I don't believe it is a code violation to run it in the same raceway, it is limited energy wiring as is the date cabling. Again, I don't think the NEC prevents it. That being said, I spent 8 years in the fire service, and the AHJ from fire department side could reject it and make you move it, even though the NEC allowed the installation. We do the entire range of installations, the only time I would intermingle fire alarm would be in a gutter situation where we had gutter feeding several limited energy systems (phone, data, HVAC, fire alarm, etc) and it could be neatly bundled and separated.

Conventional fire alarm systems are just going to be dumping 24vdc on the wire for the most part, and that generally isn't going to cause you a problem in close proximity to data cabling, also there is very little current flow on the fire alarm wire (normally).

Addressable systems with a data circuit are almost always (always when i do them) run on a shielded pair, so the data is contained on the wire inside the shield and not noisey to the surroundings. More importantly it keeps outside noise from interfering with the integrity of the life safety system (more important anyway).

We often (usually) spray paint the boxes and cover plates, and some exposed pieces of conduit red for fire alarm installations, making it quick and easy to spot for service or repair. Again, if the option is to just add another conduit for data or fire alarm and be separate, i would definately do it.

In oregon, the system would have to be installed by an electrician with at least a class A Limited Energy License, and ideally by someone with minimum of NICET level 1 certification.

your mileage may vary.


Daron J. Wilson, RCDD
daron at wilson dot org

 

[skip555]

I wont actually be installing any cabling

I was going to be doing the voice/data but it looks like that part of the job is now going to the electrcions

I wiil terminate and install and maintain phone system and network

customer was asking me what I thought about running data and fire in same conduit as that was what the electrcian was proposing (since he hadnt allowed enough conduit to run seprate) she says the alarm peaple had no problem doing it that way

I am going to call her back this morning and suggest she make the electrcion run a seprate conduit

 

[DTSMAN]

OK, I am thourghly confused. A while back I asked about sharing a conduit with coax wire with the power leads sistered to it for a camera system and was reccomended not to. No one is reccomending sharing with the low voltage lines of the fire system.
Then how is Power over Ethernet(PoE) Ok. I started a thread on this about 12 threads back. And in that thread it is OK to rob the brown pair for this which is in the twist, not just laying in another cable beside the ethernet?

 

[jimbopalmer]

So far as I know Power over Ethernet, is a IEEE standard designed to not interfere with ANY previous ethernet standard (IEEE802.3af) That gives us some hope it really doesn't.

That is NOT mixing video and data or alarms and data; which no standards body is designing specifically to co-exist. Few of us have the ime to test all the possible failure modes personally, so we tend to only accept standards. Note in this thread, no one has ANY hope the network will work while the alarms are on.

This would be vital in my network as we use VoIP 2500 feet underground and cutting off all the phones in an emergency might be viewed as a bad plan. (actually my data is over fiber optics so it is not a worry)

I tried to remain child-like, all I acheived was childish.

 

[jeffbouldin]

Bospruell,

Running 24 volt ac or 12 volt dc in a seperate wire bundled with a high quality 95% copper braided coax rated for cctv will not cause a problem. Running conventional fire alarm and security system wires with each other and cctv will not cause a problem.

Running data carrying wires (addressable loops, RS-485, keypads, network, etc.) with these and other powered wires(hore/stobes, speaker/strobes, analog phone, etc.) can cause problems. You won't always see these problems immediately, usually it gives problems when the occupents are in the building. Now on warrenty time you have to troubleshot problems that come and go. It will take awhile and fixxing it could involve rerunnig wire that is not easy to get to.

Keep each system by itself as much as possible. Save yourself time and money in the long run.

 

[Jd925]

Aside from code in your area, if they allow it with a conventional or basic zoned panel it should not be a problem BUT dont do this if the fire system is addresable. Addresable FACPS send out a tone that overpowers any toner I have used.

Jake