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Posts tagged: plenum cable

Shielded Plenum Fire Alarm Cables

Shielded plenum fire alarm cables are engineered to be used in a buildings plenum to lower the chances of a fire spreading throughout your home. They’re manufactured with a flame retardant coating such as PTFE to help cut back on the cable’s production of smoke and harmful gasses should it begin to burn. These types of cables are the ones inspectors like to see when checking a building for the best fire protection.

Fire alarm cable is used in applications when hooking up smoke detectors, signaling, fire alarm, and fire protective circuits becuase they have all been known to need the extra fire protection to continue working when a fire erupts.

EMI is electromagnetic interface which is something that an insulation cannot block a cable from. It’s “electrically noisy” and disruptive to other equipment around it which an aluminum polyester shield can block. Many fire alarm cable installations and PTFE cable installations require a strong shield in order to keep all of the equipment running smoothly.

A cable is transferring EMI to another source and the best way to block that is through the use of a shield. The shield surrounds the copper conductors which blocks any interference coming in and blocks anything going out so that all of the cables near each other can effectively do what they were set up to do.

As you can see there’s quite a bit of engineering involved in each type of fire alarm cable. If manufactured wrong or poorly they can spread a fire much faster than expected throughout the home or building. The shield could also cause problems with the EMI so it’s important to make sure the cable that you buy has all of the specifciations you need for your application.

Please call you have any questions about our shielded plenum fire alarm cable or anything else regarding the items on our website.

WesBell Electronics Inc
(800) 334-8400