3 run diagnostics, Show inputs, Test outputs – Liebert CHALLENGER 3000 User Manual

Page 20: Test control board, Run diagnostics, Caution

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Operation with Advanced Microprocessor Controls

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2.5.3 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. To test the system out-

puts, the normal system control is temporarily suspended. DO NOT leave the unit in the diagnostics

mode any longer than is necessary for troubleshooting. The control system will return to normal oper-

ation in 5 minutes, automatically, if no key is pressed.

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: 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 press switch: normally on if compressor circuit is in operation
• Comp overload: normally on unless Compressor Overload Alarm is active
• High head comp: normally off unless High Head Pressure alarm Compressor is active

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

selecting “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.” (The compressor is limited to 15 seconds

on to prevent damage.) The outputs are as follows:

• Main fan: main fan contactor
• Comp: compressor contactor
• LLSV: liquid line solenoid valve
• HGBP/CUV: hot gas bypass or compressor unloader valve (on certain units)
• Part coil: part coil solenoid valve
• CWV/CGV: chilled water or GLYCOOL valve
• R5 Relay: Relay 5 (heat rejection)
• Reheat 1: Reheat 1 contactor (also energizes fan for safety) or SCR Reheats
• Reheat 2: Reheat 2 contactor (also energizes fan for safety)
• HWR: hot water solenoid valve
• Humidifier: humidifier contactor (also energizes humidifier makeup valve and fan for safety)
• HMV: humidifier makeup valve
• Comm alarm: common alarm relay

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!

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