Chapter 4. WIRING

4 - 11 Communication Connection

RS-485 connection

SDA SDB RDA RDB SG

60 61 62 63 64

Handling Precautions

The slave station can be connected in a multi-drop configuration.

Always set a unique address to each slave station.

Attach terminating resistances (a total of four when connecting a 5-wire system) to the ends of the communications lines. Use 1/2W or greater terminating resistances of 150Ω ±5%.

If connecting three lines, short-circuit terminals (60), (62) and (61), (63).

Do not short-circuit the RDA to RDB and SDA to SDB terminals. Doing so may cause the DCP552 to malfunction.

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Honeywell DCP552 Mark II user manual Communication Connection, RS-485 connection