Honeywell UMC800 - Manual (Page 87)

Diagnostics and Troubleshooting
Overview
Release F UMC800 Controller Installation and User Guide 79
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Diagnostics and Troubleshooting
Overview
This section provides diagnostic and troubleshooting information to help in evaluating controller operating
status, diagnosing fault conditions and taking actions to correct faults. An overview of diagnostic routines
and detail of the indicators used to inform users of controller operating status is provided. Status conditions
are listed, as well as the possible cause and recommended user action for correcting fault conditions, if
necessary.
Controller Diagnostics
Diagnostic routines are executed upon power up of the controller CPU and performed continuously during
controller operation. A number of methods are used to indicate controller status to the operator. LEDs on
the CPU panel provide indication of controller power, operating mode, CPU battery status and diagnostic
status. The operator interface and the user utility program contain displays that show status and operating
parameters in more detail.
Power up diagnostics
When power is applied to the controller, a sequence of checks are performed by the controller and
completed in less than 10 seconds after power is applied. These checks are a set of internal diagnostics to
verify the integrity of the hardware, the configuration database and firmware.
• A hardware check verifies the type of I/O module present in each slot and if the module present is the
correct type for the control strategy in the controller database.
• The controller verifies that a valid configuration database is present in memory.
Communication between the operator interface and controller is established automatically after both
components have completed their restart routines and are ready to begin normal operation.