Issue
How are the Plug-In relays installed on the D8112 Control Communicator?
Solution
The Plug-In relays are inserted into the DIP (Dual IN-line Pin) sockets located on the board to enable various functions of the D8112 Control Communicator. Only three (3) relays can be installed simultaneously. Each D136 plug-in relay has two legs on one side and three legs on the other side. When inserting the relays, always ensure that the three leg side is to the left and the two leg side is to the right. Incorrect insertion will not damage the relay or the D8112, however the related circuit will not function.
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