The FW2851 isolator module isolates the short point on the SLC or DCL. The internal relay will be triggered to cut down the line power where the short trouble is detected. The device two LEDs will indicate the trouble condition from side A and side B individually by yellow lights steady on.

A return to normal condition will cause the internal relay to normal position to restore the line power and the device LED indicator will return to the idle condition.

The FW2851 does not occupy an address on the Fire Alarm Control Panel’s SLC/DCL. The FW2851 is a UL listed product according to UL864 and ULC-S527 for Fire Protective Signaling Systems for indoor use.