DIGITIZE DGM-32/64, Installation And Maintenance Manual

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DGM INSTALLATION AND MAINTENANCE MANUAL
700135-0000 Rev. O 13
2.8.2 WIRING
Field wiring for this board must be tested and connected prior to assembling the rest
of the unit. Connect the communications line(s), observing polarity, to the proper
terminals.
2.8.2.1 Terminals TX, RX & COM
These terminals are used for multiplex communications in a system utilizing RS-232
mode of communications. The RTS may be needed when interfacing to some
modem systems. The TX line indicates the SEND signal from the DGM panel. The
RX line indicates RECEIVE to the DGM panel. The COM line is the COMMON
return for both TX & RX.
2.8.2.2 P1
This connector must be plugged into P1 of the main board of the DGM. This
connector is polarized for proper insertion.
2.8.3 RATINGS
Maximum Circuit Voltage ±12VDC
Maximum Circuit Current 50 mA.
Maximum Line Impedance 100 Ohm
2.9 AUDIO MODEM INTERFACE BOARD P/N 400475-0002
(OPTIONAL)
2.9.1 GENERAL
This circuit board assembly is used to interface the two-wire Multiplex
communications line to the DGM. The Audio Modem lines are supervised. The
SYSTEM 3505 PRISM LX location must have the Audio Modem line driver for
proper interface with the optional Audio Modem interface board at the DGM. This
Audio Modem board is used when interfacing over long leased telephone lines. The
phone lines need to be a “dry pair”, suitable for voice grade communications. The
phone pair is to be a 600-ohm balanced pair with an overall signal degradation of no
more than -20 DB. The modem communications is also ideal when inter telephone
exchange communications are required. The Audio modem will operate properly on
fiber optic cable as used by the phone company for inter-exchange communications.
2.9.2 WIRING
Field wiring for this board must be tested and connected prior to assembling the rest
of the unit. Connect the communications line(s), polarity to the proper terminals is
not required with the Audio Modem.
2.9.2.1 BS1
These terminals are used for multiplex communications in a system utilizing the
Audio modem. Wires may be connected without regard to polarity.