When a fire alarm occurs, the control panel activates Relay A (Terminal 6), providing the trigger input to the “Horn” D192C/D192G. The output from Relay A also changes Point 3’s voltage to 5.0 VDC (electrically, an open condition caused by the 2.4 k. resistor), causing an alarm (burg alarm) condition. This activates Relay B (based on the Summary Alarm Relay programming shown above). Relay B provides the trigger voltage for the “Strobe” D192C/D192G. When the Fire Alarm is acknowledged at the command center, power is no longer applied to Relay A causing the horns to silence and returning Point 3 to a normal state of 2.5 VDC. However, Relay B continues to stay activated until alarm memory is cleared at the command center by using Command 4 or entering Passcode + [ESC]. After the Fire Alarm is acknowledged, the command center first scrolls the fire alarm points, then scrolls AREA 1 1 ALARMS. This occurs because Point 3 is a Burg Point. Once a Command 4 or a Passcode + [ESC] is entered, the Alarm Memory is cleared.
Part numbers D192C, D192G, D7212, D7412,D9112, D9124, D9412, D7212G, D7412G, D9112G, D9124G, D9412G
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