ABB AC500 PLC - Page 1143

1 Slave at the bus line end, bus termination with 120 W resistors
2 Master within the bus line, pull-up and pull-down activated
3 Slave within the bus line
4 Slave at the bus line end, bus termination with 120 W resistors
NOTICE!
Risk of EMC disturbances!
Unshielded cables may cause EMC disturbances.
Always use shielded cables and connect the shield at every device.
NOTICE!
Risk of malfunctions!
The pull-up resistors must be used only one time within a bus line.
Use the pull-up resistors only at 1 master.
The cable shields must be grounded Ä Chapter 2.5.4.4 “CS31 bus” on page 1214.
The following figure shows an CS31 bus with the bus master at the line end.
CS31
Slave
RxD/TxD-P RxD/TxD-N
Shield
CS31
Slave
RxD/TxD-P RxD/TxD-N
Shield
120 Ω
1
2
3
4
5
120 Ω
1
2
1 Master at the bus line end, pull-up and pull-down activated, bus termination with 120 W
resistors
2 Direct grounding clip or steel plate
If the master is located within the bus line, it does not need a terminating resistor. The pull-up
and the pull-down resistors, however, are necessary:
Connection:
CS31 Protocol
Device Specifications
Accessories > AC500-eCo
2019/04/17 3ADR010121, 13, en_US 1143