Liebert himod - Run Diagnostics; Show Inputs; Test Outputs; Test Control Board

Operation with Advanced Microprocessor with Graphics Control 23
3.8 Run Diagnostics
By selecting RUN DIAGNOSTICS, maintenance personnel can check system inputs, outputs, and
complete a test of the microcontroller circuit board, all from the front panel. Review of the system
inputs and the microcontroller test can be done without interrupting normal operation.
3.8.1 Show Inputs
With the unit on and the fan running, the input state for the following devices may be displayed:
• Air Sail Switch: normally off unless Loss of Air Alarm is active
• Custom Alarm #1: normally off unless this alarm is active
• Custom Alarm #2: normally off unless this alarm is active
• Custom Alarm #3: normally off unless this alarm is active
• Custom Alarm #4: normally off unless this alarm is active
• Humidifier Problem: normally on unless this alarm is active
• Filter Clog Switch: normally off unless Change Filters Alarm is active
• Main Fan Overload: normally on unless Main Fan Overload Alarm is active
• Shutdown Device: normally on unless unit is off through the Fire Stat or Remote Shutdown
Device
• Low Pressure Switch: normally on if compressor circuit 1 is in operation
• Compressor Overload: normally on unless Compressor 1 Overload Alarm is active
• High Head: normally off unless High Head Pressure alarm is active
3.8.2 Test Outputs
When this feature is selected, the unit is effectively turned off. When stepping from one load to the
next the previous load, if on, is turned off automatically. The loads can also be toggled on/off by select-
ing “ENTER”. Once turned on, the output will remain on for 5 minutes unless toggled off or the test
outputs function is exited by selecting “MENU/ESC” (Compressor is limited to 15 seconds on to pre-
vent damage.) DO NOT leave the unit in the test outputs mode any longer than is necessary for trou-
bleshooting. The outputs are as follows:
• Main Fan: main fan contactor
• Compressor: compressor contactor
• LIQUID LINE SV: liquid line solenoid valve
• HGBP/CUV: hot gas bypass or compressor unloader valve (on certain units)
• DEHUMIDIFY: low fan speed
• CWV/CGV: chilled water or GLYCOOL valve
• R5 Relay: Relay 5 (heat rejection)
• Reheat 1: Reheat 1 contactor (also energizes fan for safety)
• Reheat 2: Reheat 2 contactor (also energizes fan for safety)
• Comm alarm: common alarm relay
3.8.3 Test Control Board
By selecting this function, the microcontroller will perform a self test lasting approximately 10 sec-
onds. At the end of the test, the ROM checksum, ROM part number and version number will be dis-
played.
!
CAUTION
Do not test a compressor output for more than a few seconds. Compressor damage could
result!