OHAUS CKW-55, Service Manual

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CHAPTER 3 INDICATOR TESTING
3.7.3 RS422/485 Testing
The RS422/485 Communication board can be wired to operate in a 4-wire duplex or 2-wire half duplex
mode. When RS422/485 is installed, note the jumper arrangement shown in Figure 3-10 and 3-11
RS422/485 Typical 4-Wire and Typical 2-Wire Connections.
Note : W1 must be shorted to allow 2 wire communications.
W2 must be shorted on the last scale connecting to the communcation link. W2 connects the
terminating resistance.
Figure 3-9. RS422/485 Typical 4-Wire Duplex Connection.
Figure 3-10. RS422/485 Typical 2-Wire Half Duplex Connection.