ASEA AC55LC-3, Operation Manual

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AC55LC-3, AC63LC-3, and AC75LC-3 Operations Manual....
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6.5 REMOTE COMMUNICATIONS, cont.
6.5.2 RS-485, cont.
All wiring between the converter’s RS-232C port and the Modbus Option converter/optical-isolator
is included and wired at the factory. RS-485 bus wiring between a master converter and slave
converter(s) and ultimately to the customer side connections is the responsibility of the customer.
Such wiring should be shielded as depicted in Figure 11 on the previous page.
Each converter/optical-isolator contains terminating jumpers used to link the T1 and T2 terminals to
the B and A terminals, respectively, and provide internal terminating resistances. Install such
jumpers as indicated in Figure 11 at the first and last device in daisy-chained RS-485 bus, but
remove the jumpers for any intermediately connected devices.
A master converter’s Node Id is factory set for 3; a slave converter’s is set for 4. These are the
default values for communication with ASEA Power Systems designed Touch Panel computers.
Additional slave converters can be set for Node Id numbers greater than 4 (5-8 recommended). As
ASEA Power Systems uses Node Id numbers 9-13 for GMM products, use of these should be
avoided.