Ingersoll-Rand Thermo King CRR DF MPC2000, Maintenance Manual

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Microprocessor Controller
General Description
The MPC2000, MPC2000ID and MP3000 are advanced microprocessor controllers that have been
specially developed for control and monitoring of refrigeration units. Each controller contains the
following basic features:
1. Eight status indicator LEDs are located in the top LED display and signal the following:
• Supply (Air Temperature)
• Return (Air Temperature)
• Humidity Mode (Inactive on CRR DF units)
• Compressor (Cooling On)
• Heat (On during Defrost)
• Defrost
• In-Range (Temperature)
• Alarm
The indicator LEDs stay ON continuously to indicate sensor temperature display, unit operating mode
or condition.
The Alarm LED flashes ON and OFF continuously when a Check Alarm (Level 2 Alarm) or
Shutdown Alarm (Level 1Alarm) occurs. Less serious Log Alarms (Level 3 Alarm) are recorded but
do not activate the Alarm LED.
Check Alarms indicate corrective action should be taken before a problem becomes severe. The unit
continues to operate. However, some unit functions may be inhibited.
Shutdown Alarms indicate the unit operation has been stopped to prevent damage to the unit or cargo.
The problem must be corrected and the alarm code acknowledged before the unit can be restarted to
resume normal operation.
Alarm codes are recorded in the controller memory to simplify unit diagnosis procedures. Some alarm
codes are only recorded during a Pretrip (PTI) Test. Fault codes are retained by the controller in a
non-volatile memory (see alarm codes, type and description below).