Honeywell ComfortPoint Open CPO-PC400-W Manual page 26

CPO-PC400-W/CPO-PC400-UW HVAC CONTROLLER
CONNECTION VIA RS485 INTERFACES 1, 2, OR 3
R
T
5V_ISO
GND_ISO
Isola on
Barrier
5V
GND RX TX
CPO-PC400-W/CPO-PC400-UW
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.
EN0B-0085 IE10 R0420
110VAC/230VAC
24VAC
F1
26
L > 3m
FBA #1
Shielding
Op onal
A
F2
24VAC
110VAC / 230VAC
FBA #N
R
T
A+C = MAX.20 Meters
C