Chapter 4. WIRING

3-wire system RS-485 connection diagram

Terminating resistor

Master station

RDA

RDB

SDA *

SDB *

SG

FG

Shield

Shield

Terminating resistor

Slave station side DCP552

60SDA

61SDB

62RDA

63RDB

64SG

FG

Shield

Slave station side DCP552

60SDA

61SDB

62RDA

63RDB

64SG

FG

Slave station side DCP552

60SDA

61SDB

62RDA

63RDB

64SG

FG

Attach 1/2W or greater terminating resistances of 150Ω ±5% at each end of the communications lines. Ground the shield FGs at one end in one location, not at both ends.

When only three RS-485 terminals are provided, the areas designated with an asterisk (*) are connected internally.

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Image 43
Honeywell DCP552 Mark II user manual Terminating resistor Master station