Description
Under normal conditions, the 4090-9117 Addressable Power Isolator provides continuity between ports. In the event of a short circuit, or if requested from the FACU, the isolator opens a two-pole electronic switch, isolating both power circuit conductors.
Isolators power-up in isolation mode and are directed to connect by the FACU. If the output wiring is acceptable, the isolator connects to the rest of the circuit. If the output wiring is shorted, the isolator remains isolated.
The isolator reports to the FACU when it is in isolation mode and the extent of shorted wiring is available at the FACU by identifying noncommunicating device addresses. Isolators are assigned sequentially to low number addresses to expedite Signaling Line Circuit (SLC) power-up.
Refer to Installation Instructions 574-873 for additional information.
During system installation, earth faults frequently occur and extensive wiring disconnection is often required to find them. With the Addressable Power Isolator, you can quickly locate earth faults on fire alarm system power wiring to expedite repair.