sundance-communications.com/forum Forums Wiring - Telecom Carriers - Trunks & Services Security, Alarms and Paging Splices in Fire Alarm Panels

I don't have my copy of NFPA 72 with me, but I thought there was a provision that fire alarm cables cannot be spliced; that if they were separated the cut ends must be terminated on a device.

This is NOT my work. I happened to look in a panel being done by another contractor that is next to the phone board I'm doing. He cut a couple of his wires short in the panel and put them together with wire nuts (using extension wires that aren't even the same color!).

If there is a provision, please let me know particular section so that I can search for it on the web.

Thanks,
Bill

I see it quite frequently...but again not sure if it's legal...

I don't know either. FA is a specialized trade that I have not done. I kinda think it is OK in the panel but...

You could ask this over at the Mike Holt sparkie board. There are guys there that would know.

-Hal

I'd actually go to FireNet Online BBS

Just like this forum, except for Fire and Security only.

Thanks, all. Looks like it's OK as long as it's in a listed enclosure.

Bill

Splicing is ok as long as it's in an enclosure such as the panel cabinet or a junction box.

To expand a little, splicing is ok because if installed correctly everything in a fire panel is supervised one way or another.
The strobe/horn (NAC) circuits are supervised with the use of an End Of Line resistor. (EOL)
Device loops are also supervised by an EOL.

Communication circuits on addressable systems are not monitored by an EOL because the devices check-in every few seconds.

If the loop is cut or a splice becomes open the panel should indicate a trouble within seconds of the fault.
On addressable systems the panel would no longer get the check-in signals and would indicate a trouble accordingly.

Sorry for the long post. I just wanted to elaborate a little on this subject because I've been ask the same thing in the past by the electricians.

On the big job I did this summer, in which the alarm guys had a field day, they had a big junction box above the ceiling in a newer part of the building with a ton of splices in it. I think they ran a multi-conductor cable from the alarm panel and spliced the individual device runs into it. As you can imagine it was a huge mess.

Just like a multi-pair telephone cable, it all makes sense to the trained eye.

Splices are just a part of life in the fire alarm business. Mainly because the fire alarm does so much more than making noise to let everyone know to get out of the building.
Another equally important thing fire alarms do is help prevent the spreading of the fire and smoke throughout the building as well as unlocking magnetic door locks to allow people to exit and Firefighters entrance through what would normally be locked doors.

In order to accomplish this the panel will shut air handlers down, close dampers, release fire doors being held open by magnetic door holders, and they also take control of the elevators to send them away from the fire and prevent people from using them during a fire. The Firefighters can use the elevators by overriding the fire panel control with a Fireman's elevator key.(As they did in the Towers on 911) But even the fire key will be overridden by the fire alarm panel if there is a fire in the elevator equipment room or the elevator shaft. If there is a fire in either location the fire alarm panel will kill all power to the elevator equipment and there ain't nobody gonna use it after that.

And if all of that isn't enough, the fire alarm also monitors water flow from sprinkler systems as well as fire suppression dump systems above cooking grills, etc...
I'm sure I'm leaving out a lot of other things they do but you get the idea.
Bear in mind on large systems, such as a hospital system, this is not all done by a single panel but by several panels and expander panels that are all tied together to function as a single unit at all times.

As you can see, it's just not feasible to home run every cable. Hence the need for splices.

So the next time you stay in a hospital or a big hotel and you see a fire alarm pull station you can sleep a little more comfortably knowing that the system it's attached to may mean the difference between life and death in the event of a fire and it's probably doing a lot more than waking you up with a loud noise!

Bobby,
Thanks for the explanation.
Bill