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    How To: Use Dual Phone lines on the B8512G or B9512G.

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    The use of dual phone lines in B8512G and B9512G panels is accomplished by using two B430 Plug-in Telephone Communicator modules. The additional phone line must be enabled by selecting ‘Two Phone Lines=Yes' in programming as described in the below figure:

    1. Enter the receiver phone number(s).
    2. To supervise phone lines make an entry in: Phone Supervision Time.
    3. Select Two Phone Lines=Yes.

    Using Dual Phone Lines B-G panels.png


    There are two slots in B8512G and B9512G panels for the B430 Plug in Telephone Communicator module labeled Mod 1 and Mod2.

    • The B430 plugged into the MOD-1 connector on the control panel is Phone Line 1.
    • The B430 plugged into the MOD-2 connector on the control panel is Phone Line 2.

    Upon power up the panel will begin sending phone reports using the B430 module in Mod-1. Each time a test report is sent the panel will switch from the B430 currently in use to the other currently idle B430.

     Telephone line monitor

    The B430 module has a built-in telephone line monitor that tests the telephone line for voltage and current. The normal voltage on a telephone line is approximately 48 VDC (24 VDC for some telephone systems). If the module senses trouble, it starts a programmable telephone line trouble timer, which continues to run as long as the monitor detects trouble. It resets to zero when the control panel senses a normal line. If the timer reaches the delay time in the Phone Supervision program item, it begins a telephone line trouble response. Programming determines what the response is. For programming information, refer to Phone Parameters in RPS Help or in the control panel Program Entry Guide.

     Communication failure

    If the control panel has a backup route configured and the first two attempts to reach the receiver over the primary phone line fail, the system switches to the backup route. When it switches to the backup route, it sends a trouble event, and the event that triggered the telephone call to the central station follows. After ten unsuccessful attempts to reach the receiver, the control panel enters communication failure. The control panel clears any reports queued for the failed route and generates a COMM FAIL event that shows on the keypads. A trouble sounder can be programmed to annunciate at the keypads. One hour after a COMM FAIL event, the control panel attempts to send a COMM RSTL event. If a communication failure still occurs, the keypad trouble sounds again.

    B8512G, B9512G, B5512, B430, D928, Dual, Phone, Line, Module, Communicate, Telephone

    Version history
    Last update:
    ‎05-14-2018 04:53 PM
    Updated by: