‘Normal’, ‘Defect’ and per circuit ‘Fire’ indication on front panel ‘Internal Bell Cut-Off’ and ‘External Bell Cut-Off’ (BCO) Alarm reset available from a front panel key-switch Trial Evacuation key-switch Fire & Defect C/O relays with Fire relay Isolate switch Automatic Alarm Verification Facility (AVF) provides substantial protection against transient false alarm activation Supervised bell circuit with 10 kΩ EOL resistor Maximum of two 20 Watt 100 Vrms line amplifiers with voice evacuation message ‘Battery Absent’ detection circuitry Earth leakage supervision Integrated Alarm and Defect piezo for audible warning On-board System ‘Defect’ LED indicates source of fault Door Interlock Brigade ‘Isolate’ and ‘Test’ switches Electrically isolated interface to an alarm transmitter (SGD) DBA mode ‘Non Latching, Bell Only’ configuration available (on Circuit 4) Automatic daily load test with automatic ‘Battery Absent’ detection circuitry