Honeywell UDC2800 - Procedure #7; Procedure #8

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Procedure #7
This table explains how to troubleshoot a Keyboard failure.
Table 8-11: Troubleshooting a Keyboard Failure
Step What to do How to do it
1 Make sure the keyboard is
connected properly to the
MCU/output and
power/input boards.
Withdraw the chassis from the case and visually
inspect the connection.
2 Controller Keyboard or
specific keys may be
LOCKED OUT via the
security code.
Use your four-digit security code number to
change the lockout level. See Configuration for
more information.
3 Run the keyboard test. Press the Setup key and hold in, then press the
Function key at the same time. The controller will
run a display test. Then you will see Try keys in
the Lower Display.
Press each key. If it works, the key name will
appear in the Lower Display.
4 Replace the
display/keyboard if any
keys do not function.
Refer to “Parts Replacement Procedures” in this
section.
Procedure #8
This table explains how to troubleshoot a RS 485 Communications
failure.
Table 8-12: Troubleshooting a RS-485 Communications Failure
Step What to do How to do it
1 Check the Address Number,
ComState and Baud Rate settings.
See Communications Group for more
information.
2 Check the field wiring and
termination resistor.
Using an ohm meter, check the
resistance across the communications
rear terminals. See Section for wiring
diagrams.
Chapter 8 - Troubleshooting/Service