IM 1044-2
Centrifugal Chillers
35
Figure 21, Communication Wiring
NOTE
: A fourth chiller, Chiller D would be connected to chiller C same as chiller C to chiller B.
Chiller A
PIGTAIL
485
OPDR
C
A
B
UCM
J10 J11
BLU/WHT
WHT/BLU
SHIELD
(+)
(-)
UNIT CONTROL
J11 PORT
Chiller B
485
OPDR
C
BLU/WHT
WHT/BLU
SHIELD
B A
UCM
J10
PORT
Chiller C
(+) (-)
J11 Port
UNIT CONTROL
UNIT CONTROL
P
P
P
P