DIGITIZE DGM-32/64, Installation And Maintenance Manual

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700135-0000 Rev. O 19
3 SYSTEM INITIALIZATION
3.1 GENERAL
For initial set-up of the Data Gathering Module, the following instructions should be
carried out in the order in which they appear. However, if during the operation of the
unit, it should become necessary to set the time on the internal clock, this can be
done without going through the powerup sequence.
3.2 ASSEMBLY
Mount the front plate, if not already installed, with the four mounting screws.
3.3 CONNECTIONS AND SETTINGS
3.3.1 ZONE INPUTS
An End Of Line resistor should be connected across each pair of zone input
terminals. There are two screw terminals for each zone input. The zone inputs CAN
NOT have any terminals connected to system common. After testing the unit, the
EOL resistors supplied with the unit should be removed and one placed on the last
device of each zone input line. Should the resistor not be removed and field wiring is
installed on that line, there will be NO supervision of that line.
3.3.2 MUX DATA LINE
The system can be supplied with several different data line inputs. Inputs include
RS-422/ 485, Audio Modem, RS-232, Fiber Optic and Polling Radio. The multiplex
data line is connected to the appropriate data input terminals on the data interface
board. The polarity of the multiplex data line must be observed for RS-422/485, RS-
232, and Fiber Optic. The maximum length for the multiplex data line is based on the
data type selected. RS-422/485 have been used successfully up to 17 miles with a
dry cable pair. The RS-232 can be used for up to 1000 feet. The Audio Modem can
be used at any distance with proper amplified telephone lines. The telephone lines
can be standard voice grade, 600 balanced with a total loss of up to 20 DB end to
end. The Style 7 Fiber Driver can drive a 62 Micron fiber for three miles or 20DB
total loss. The signal is reshaped and retransmitted at each DGM panel. Thus total
distance is unlimited as long as you have a DGM panel every three miles. The
Polling Radio Interface uses a radio transmitter and receiver to transmit data. The
maximum distance that this interface can communicate is determined by the height
of the antenna, the physical terrain, and the amount of radio interference on
adjacent radio frequencies. A site propagation test must be completed to determine
how well the Polling Radio will work. Contact the factory for assistance with data line
and style selection.