MP4000 Controller

The MP4000 is an advanced microprocessor controller. It has been specially developed for the control and monitoring of refrigeration units. The controller contains the following basic features:

  • Temperature/Message Status Display

    • Temperature area: Displays return air sensor, supply air sensor, and setpoint.

    • Message area: Displays alarms, message, and controller menu.

  • Keypad

    • F1 - F4 Function keys navigate within the Status Display.

    • Two Status LED indicators.

    • Special function keys: ON/OFF, PTI, Defrost.

Parent topic: Controller Description

Back-up Battery

Every Controller has a Back-up Battery. This will allow the controller to be energized if the unit is not connected to shore power. The technician can change settings in the controller - Setpoint, etc.

Press the ON/OFF key, the controller will energize and stay energized for 25 sec, by pressing any of the Menu keys the 25 sec timer will reset to 20 sec.

Input and Output Signals

The MP4000 microprocessor controls all unit functions to maintain the cargo at the proper temperature. The controller also monitors and records system faults and performs pretrip.

The MP4000 controller uses advanced solid-state integrated circuits to monitor and control unit functions. The controller monitors inputs from:

  • Return Air Sensor

  • USDA (Spare) Sensors 1, 2, and 3

  • Current measuring circuits

  • Compressor HT feedback signal (R134a)

  • Supply Air Sensor

  • High Pressure Cutout Switch/Discharge Pressure Sensor

  • Voltage measuring circuits

  

  • Evaporator Coil Sensor

  • Suction Pressure Sensor

  • Compressor Discharge Line LT Temperature Sensor (R23)

  

  • Ambient Sensor

  • Phase measuring circuits

  • Compressor Discharge Line HT Temperature sensor (R134a)

  

Output signals from the controller automatically regulate all unit functions including:

  • Condenser fan operation

  • Electric heaters

  • Compressor LT operation

  • Liquid Solenoid Valve

  • Evaporator fan motor operation

  • Phase selection

  • Compressor HT operation

  
MP4000 Display Panel
      
  1 Standard Display
  2 Function Keys
  3 Special Function Keys