Rice Lake Signal Conditioning Transmitter/Indicators - Manual (Page 30)

26 SCT Weight Transmitter Operator’s Manual
2.9.1 RS-485 Serial Communication
Figure 2-8. RS-485 Serial Communications
If the RS-485 network exceeds 100 metres in length or baud rate over 9600 are used, close the two jumpers,
called "RS-485 termination", to activate two 120 ohm terminating resistors between the ‘+’ and ‘–’ terminals of
the line, on the terminal strip of the furthest instrument. Should there be different instruments or converters,
refer to the specific manuals to determine whether it is necessary to connect the above-mentioned resistors.
8
1
7
1
8
1
7
1
8
1
7
1
SCT
SCT
SCT
RS48
5 +
R
S
485 -
max 500 m
RS485 +
RS485 -
PC RS232
RX+ RX- TX- TX
+
Converter
24 Vcc
+
-
0 TX RX VI
N
RS
4
8
5 +
R
S
485 -
RS
4
8
5 te
rmination
20
2
0
0 VDC 20
RS485 +
RS485 -
0 VDC
RS485 +
RS485 -
0 VDC
5 2 3
If your device is labeled A and B
• Connect A to RS485-
• Connect B to RS485+
Note