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OPERATION

The matrix interface circuit board provides an isolated optical coupler connection for each alarm zone. (See the individual input circuit diagram.) Activation of an alarm input is accomplished by providing a voltage between Terminal A and Terminal C for that alarm input in the same manner that an LED is activated.

WARNING: Connecting an improper voltage will cause failure of the encoder circuit board.

INSTALLATION

The matrix interface circuit board is provided already mounted and connected to the MMP encoder circuit board. This is because the interface requires several connections to the encoder which are not easily accomplished in the field.

Connect each alarm input zone by connecting the Terminal A (anode) and Terminal C (cathode) connections to the appropriate anode and cathode connections on the matrix driver (output) circuit. Be very careful to check each connection and not cross any connections between outputs. A cross-connected matrix can possibly cause failure of the matrix circuitry and the MMP encoder input circuitry. Do not activate the MMP encoder or the alarm matrix connected to it until all wiring has been connected and tested.

TESTING

The matrix interface circuit board does not allow simple one-wire testing of inputs (see manual). The operation of the MMP encoder is best tested using the test button located on the circuit board (see manual).  If individual testing of each alarm input at the matrix interface circuit board is required, an appropriate isolated voltage and a suitable current limiting resistor is required. Consult CDT for details.