
CPO-PC400-W/CPO-PC400-UW HVAC CONTROLLER
23
EN0B-0085 IE10 R0420
Recommended connection for BACnet MSTPMSTP Buses with non-isolated RS485
Interfaces
Fig. 14. Connection (L > 3 m) of RS485 interfaces 1, 2, or 3 (RS485 interface 1 shown) to a BACnet Bus
NOTES:
—
Always power the CPO-PC400-W/CPO-PC400-UW with a transformer separate to the connected BACnet MSTP
modules.
—
N = max. 30 modules
—
Signal ground (signal reference) connection is recommended if not all devices are electrically isolated. For more
information, see “General Information on the RS485 Standard” section on page 7.
TX
5V
GND
#1
Isolaon
Barrier
RX
5V_ISO
GND_ISO
R
S
485+
R
S
485-
R
T
110VAC/230VAC
24VAC
#N
F1
R
S
485+
R
S
485-
FG
N
D
L > 3m
R
T
R
S
485+
R
S
485-
FG
N
D
CPO-PC400/CPO-PC400-W/
CPO-PC400-UW
FG
N
D
24V0
24V~
CH1+
CH1-
GND1