beautypg.com

Laurel Electronics LAUREATE SERIES DPM User Manual

Page 40

background image

-38-

15.

RS-232 AND RS-485 INTERFACE

15. 1 JUMPER SELECTIONS

RS232 Interface

Jumper g - installed for normal operation
Jumper h - installed when used as a slave display
with the RS232 output of another Laureate meter.
Jumper j - provides a pull-up resistor on the RTS
line.

Note: The board is shipped standard with jumpers g

and j installed

RS232

RS485

RS485 Interface

h

g

j

a

d

c

b

f

e

Note: Bias jumpers b and e must be
installed on board for proper operation. If
the outputs of more than 1 RS485 are
connected together, then 1 (AND ONLY 1)
RS485 board must have the jumpers
installed.

Full Duplex

Jumpers b and e - bias jumpers installed on
1 board
Jumpers a and d - are installed with long cable
runs and add 121 ohm load resistors. If mul-
tiple meters are on same line, only the last
meter in the line should be jumpered.

Half Duplex

Jumpers b and e - bias jumpers installed on 1 board
Jumpers c and f - installed for half duplex operation
Jumper a - is installed with long cable runs and add a 121 ohm load resistor. If multiple
meters are on same line, only the last meter in the line should be jumpered.

Note: The board is shipped standard with no jumpers installed