MP-5000 Controller Specifications

• Manual Switch or Demand Defrost Initiation: Coil must be below 18 C (65 F). Defrost cycle starts when technician or controller requests defrost initiation.

• Timed Defrost Initiation: Coil must be below 4 C (41 F). Defrost cycle starts one minute after the hour immediately following a defrost timer request for defrost initiation. For example, if the defrost timer requests a defrost cycle at 7:35, the defrost cycle will start at 8:01. Datalogger will record a Defrost event for each interval in which a Defrost cycle is pending or active (i.e. both the 8:00 and 9:00 data logs).

Demand defrost function initiates defrost when:

• Temperature difference between the return air sensor and defrost (evaporator coil) sensor is too large for 90 minutes.

• Temperature difference between the supply air sensors and return air sensor is too large.

Evaporator Coil Temperature must be below 5C (41 F) to activate the defrost compressor hour timer.

There is an interval set for defrosting, however, the defrost timer is built intelligent - it detects whether or not there is ice building up on the coil. If there is no ice building up on the coil, it extends the defrost interval, and if there is Ice building up earlier on the coil it reduces the defrost interval. The maximum interval is 48 hours.

• Chilled Mode: Terminates defrost when coil sensor temperature rises to 18 C (65 F).

• Frozen Mode: Terminates defrost when coil sensor temperature rises to 18 C (65 F).

• Flow High: High speed only.

• Flow Low: Low speed only.

• Flow Cycle: Fans will cycle between low and high speed every 60 minutes.