3
System Wiring
• When there are multiple controllers in the system, each
controller is assigned a unique address code from 0 to 15.
Duplicate addresses are NOT allowed.
• After a central controller is connected, DO NOT use an
ohmmeter to test signal cable resistance. This should be
done before the central controller is connected.
• Control cable is polarity sensitive and MUST NOT be
cross-connected. See Fig. 5 for correct connections.
• See Fig. 6 for complete system central controller wiring
diagram.
X
X
Y
Y
E
E
CENTRAL CONTROLLER
OUTDOOR UNIT
a40-1875
Fig. 5 — Controller Connections
P Q E
X Y E
3 4 (
3 4 (
3 4 (
3 4 (
3 4 (
5
&
) ) (
; <
(
MATCH RESISTANCE
OF COMMUNICATION
TERMINAL 120
Ω
MATCH RESISTANCE
OF COMMUNICATION
TERMINAL 120
Ω
OUTDOOR
UNIT
CENTRAL CONTROLLER
24 VAC
POWER
INDOOR UNIT
INDOOR UNIT
INDOOR UNIT
INDOOR UNIT
CONTROL BOX
INDOOR UNIT
CONTROL BOX
CONTROL BOX
CONTROL BOX
CONTROL BOX
GROUND THE
SHIELD AT EACH
CONNECTION POINT
ONE CENTRAL CONTROLLER CAN CONNECT UP TO A MAXIMUM OF 64 INDOOR UNITS
a40-1881
Fig. 6 — Central Controller System Wiring
