INFICON IO1000 I/O module - Manual (Page 12)

12
Description
RS485 i
Connection for RS-485
A: Active bus terminator
B: Without bus terminator
C: Passive bus terminator
Galvanic isolation (max. 60 V DC, 25 V VAC against GND)
Pin assignment:
The bus terminator integrated in the I/O module (120 Ω) between D+ and D can be
disabled via DIP switches S2-4. The BUS address is 1. BUS operation with more
than two subscribers is not possible.
STATUS-LED c
Fig. 5 RS-485 bus terminator
1
2
3
4
5
562 Ω
120 Ω
562 Ω
DIP S2-4
RS485
D+
D-
+5 V
0 V
I/O-Modul A
1
2
3
4
5
562 Ω
120 Ω
562 Ω
DIP S2-4
RS485
D+
D-
+5 V
0 V
I/O-Modul B
1
2
3
4
5
562 Ω
120 Ω
562 Ω
DIP S2-4
RS485
D+
D-
+5 V
0 V
I/O-Modul C
Pin Name
1 Connect pull-up resistor (562 Ω against +5 V) with D+ if necessary
2 D+
3 D-
4 Connect pull-down (562 Ω against GND) with D- if necessary
5 COM
Color Status Meaning
Red illuminates Unit not functional or defective
Red flashes Not ready for operation, communication to leak
detector is not available
Cyan illuminates Ready for operation; communication to leak
detector available
Green Flashes quickly Boot loader active, ready for software update
Green Flashes slowly Data reception on RS232
Yellow Flashes slowly Data reception on RS485
– off No operating voltage