Rs485 Communication - SKF Multilog IMx-S Series User Manual

RS485 Communication

Twisted pair shielded cable shall be used.
Important - Connect the shield only at one end to avoid ground loops.
The cable connection should be according to the following:
Table 3-7: Cable connection.
IMx-S
RS485 A Out
RS485 B Out
If the IMx-S unit is at the end or beginning of the RS485 Bus, activate the built-in
termination resistor by setting DIP21 according to the table below. DIP21 can be
accessed after the front panel has been taken off. It is located below the Dig3 DIP switch.
Table 3-8:
DIP21 settings
position: 1234
0100
0000
DIP21 settings
position: 123456
011010
001010
This 2-wire RS485 communication supports Modbus RTU protocol in which the IMx-S can
be configured as a Modbus master or as a Modbus slave device. For more information
regarding RS485/Modbus and the different configurations that are supported, refer to
the appropriate user manual, "Modbus for SKF IMx and @ptitude Observer" o Modbus
for SKF IMx and @ptitude Analyst a d also the appli atio
Protocol Considerations for IMx-Devices" .
SKF Multilog On-Line System IMx-S
User Manual – Revision S
RS485 Equipment
A
B
➢ On newer systems there is a hole in the front panel for DIP21 (no
need to remove front panel).
.
DIP21 functionality
Functionality with I/O board version less than
v1.24 (DIP21-switch with 4 positions)
Termination resistor enabled RS 485
Termination resistor disabled RS 485
Functionality with I/O board v1.24 or greater
(DIP21-switch with 6 positions)
Termination resistor enabled
Termination resistor disabled
Figure 3 - 4.
Front Panel with DIP21 Hole (I/O board v1.24 or Greater).
Unit Configuration
RS485 Communication
ote Ge e al Mod us
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