Installation Instructions
Table Of Contents
CPO-PC400-W/CPO-PC400-UW HVAC CONTROLLER
EN0B-0085 IE10 R0420 26
CONNECTION VIA RS485 INTERFACES 1, 2, OR 3
Fig. 17. Connection (L > 3 m) of RS485 interfaces 1, 2, or 3 (RS485 interface 1 shown) to a Field Bus
NOTES:
— Signal ground (signal reference) connection is recommended. For more information, see “General Information
on the RS485 Standard” section on page 7.
— N = max. 31 unit loads.
— The size of the transformer must always be calculated according to the power consumption of the connected
FBAs.
— For communication cable lengths, transmission speeds, and termination, see “General Information on the
RS485 Standard” section on page 7. For fusing, see “Fusing” section on page 11.
TX
5V
GND
FBA #1
Isolaon
Barrier
RX
5V_ISO
GND_ISO
RS485+
RS485-
R
T
110VAC/230VAC
24VAC
FBA #N
F1
Field Bus +
Field Bus -
24VAC-COM
L > 3m
R
T
24VAC
Field Bus +
Field Bus -
24VAC-COM
24VAC
Shielding
Oponal
FGND
24V0
24V~
CH1+
CH1-
GND1
24VAC
110VAC / 230VAC
F2
A
C
A+C = MAX.20 Meters
CPO-PC400-W/CPO-PC400-UW