FUTEK IPM500 (D500) Digital Display - Manual (Page 6)

Another alternative for RS-485 is to use an RS-232 to RS-485 converter that plugs into the
computer RS-232 receptacle external to the computer and is powered from a +9V DC wall plug-in
adapter. One such unit is the B & B Electronics Model 485OT9L.
3.4 JUMPERS SETTINGS OF METERS, COUNTERS & TIMERS
RS232 Board
g Normal operation.
h Slave display operation to RS232 output of
another meter.
J Pull-up resistor on RTS line.
Note: The RS232 board is shipped standard with
jumpers g and j installed.
RS485 and RS485-Modbus Boards
Full Duplex Operation
b & e These bias jumpers should be installed on 1
(and only 1) meter.
a & d Installed on last meter in line with long cable
runs.
Half Duplex Operation
b & e Bias jumpers installed on 1 board.
c & f Installed for half duplex operation.
installed on last meter in line with long cable runs.
Note: RS485 and RS485 Modbus boards are shipped standard with no jumpers installed.
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