Omega CN1166 manual DC Outputs, 1.3.11 RS485 Serial Communications Link

1.3.10DC Outputs

See Appendix A.

1.3.11RS485 Serial Communications Link

The cable used should be suitable for data transfer at the selected rate (1200, 2400, 4800 or 9600 Baud) over the required distance. Transmitters/receivers conform to the recommendations in the EIA Standard RS485.

The “A” terminal (Terminal 11) on the Profile Controller should be connected to the “A” terminal on the master device; the “B” terminal (Terminal 12) on the Profile Controller should be connected to the “B” terminal on the master device. Where several Profile Controllers are connected to one master port, the master port transceiver in the active state should be capable of driving a load of 12k￿ per Profile Controller; the master port transceiver in the passive state must have pull-up/pull-down resistors of sufficiently low impedance to ensure that it remains in the quiescent state whilst supplying up to ￿100￿A each to the Profile Controller transceivers in the high impedance state.

NOTE: The RS485 Serial Communications option and the Remote Run/Hold option are mutually exclusive.

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