Fire Alarm wires mixed with other wires

[ngd4130]

Can someone clarify if you can mix fire alarm cables with other cables through bridal rings through open ceilings or plenum ceilings?

 

[barbeer]

Article 760 refers to different circuits in same enclosure, cable or raceway. I do not see a bridle ring as any of those so IMHO there are no problems with this installation. There are some variables to the situation that are addressed in the article so do your homework.

 

[Cecilt22]

Mixing with other cables can cause operatonal problems with FACP's. The proximity of other voltages (usually higher than 24vdc) leave you open to creating communication problems with the SLC loops. You also have to worry about cross inductance hurting FACP components. The FA systems I install I take great pains to isolate from higher power sources (reduces potential call backs).

 

[Fire Alarm]

I have run Fire Alarm cables in cable trays with telecom and datacom cabling and had no problems. Fire Alarm cable is also available with shielding if you anticipate possible interference issues.:smile:

 

[don_resqcapt19]

What are the other cables? Take a look at 760.55(G). As long as the other cables are not electric light, power, Class 1, non–power-limited fire alarm, or medium power network-powered broadband communications circuits, then you are permitted to install them without separation. Note this is per the code rules, the manufacturer may specify otherwise.
Don

 

[pgordon]

The shielding on fire alarm cables keeps the noise in. the new lightning speeds are even quieter. More and more facp do not require sheilds or drains.