Honeywell UDC3300 - Table 7-12 Troubleshooting a Communications Failure

82 UDC3300 Limit Controller Product Manual 1/01
7.7 Troubleshooting Procedures, Continued
Procedure #5
Table 7-12 explains how to troubleshoot a Communications failure.
Table 7-12 Troubleshooting a Communications Failure
Step What to do How to do it
1
Check the field wiring and
termination resistor.
Refer to the Installation section of
either the RS422/485 Manual or the
Gateway Manual depending on the
protocol used.
2
Make sure the Communications
Printed Wiring Board is installed
properly in the controller.
Withdraw the chassis from the case
and inspect the board. See the
exploded view (Figure 8-1) for location
of the board. Return the chassis to the
case.
3
Determine if the Communications
board is faulty by running a LOCAL
LOOPBACK TEST.
If the test fails, replace the board.
Run the Local Loopback Test.
Press [SET UP] until you see:
COM
Lower Display
SET UP
Upper Display
Press [FUNCTION] until you see:
LOOPBACK
Lower Display
DISABL
Upper Display
Press s or t, you will see:
LOOPBACK
Lower Display
ENABLE
Upper Display
The test will run until the operator
disables it here.