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CPO-PC400-W/CPO-PC400-UW HVAC CONTROLLER
EN0B-0085 IE10 R0420
36
TROUBLESHOOTING WITH LEDS
Troubleshooting with LEDs of RS485 Interfaces 1, 2, 3
Troubleshooting with the Ethernet Interface LEDs
Table 30. CPO-PC400-W/CPO-PC400-UW Tx and Rx LEDs of RS485 Interfaces 1,2, and 3
Case
LED Behavior
Meaning
Remedy
1
Both LEDs of given interface
flashing.
Bus is functioning properly.
No action is necessary.
Bus is not functioning properly.
Check termination. Check the
polarity of bus connections.
Check for EM interference.
2
Both LEDs of given interface are
OFF.
No communication over given
interface.
Use ComfortMan to check
interface assignment in the
application. Check the wiring.
Table 31. CPO-PC400-W/CPO-PC400-UW link and activity LEDs of Ethernet interfaces 1 and 2
Case
LED Behavior
Meaning
Remedy
1
Yellow LED is ON steadily
Ethernet is working with
connectivity below 100Mbps.
If communication problems
persist, then check green LED.
See Case 3 and Case 4 given
below.
2
Yellow LED is OFF
• If green LED is ON or flashing,
then Ethernet is working with
connectivity below 10Mbps.
• If green LED is OFF, then
Ethernet is disconnected
Connect the cable between the
controller and the switch.
3
Green LED is flashing
Normal operation. The controller
is transmitting/receiving data
to/from the switch via cable.
If communication problems
persist, the Ethernet parameter
configuration may be defective:
Check IP address, MAC address,
and firmware.
4
Green LED is ON
Ethernet connectivity exists but
no data flow.
Check the software configuration.
5
Green LED is OFF
Ethernet port link is down.
• Check the cable connection
between the controller and the
switch.
• Check the switch.
• Use good a laptop or good
cable to directly connect
the controller and the switch