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APPENDIX 3 DIGITAL INTERFACE
AP-32
Serial Interface
LTC1535
TD-A
TD-B
ISOGND
RD-A
RD-B
PC-400
RD-H
RD-C
110 ohm*
470 ohm
Processor Unit: IEC 61162-2/1 input/output
Sensor Adapter: IEC 61162-2/1 input/output
TD-A
SN65LBC172
TD-B
10 ohm
10 ohm
10 ohm
Processor Unit: IEC 61162-1 output
Sensor Adapter: IEC 61162-1 output
Processor Unit: IEC 61162-1 input
Sensor Adapter: IEC 61162-1 input
PC-400
RD-H
RD-C
470 ohm
* Set with jumper.
Open/close switchable.