The microprocessor-based digital temperature controller performs the functions of controlling the enclosure temperature while monitoring operating limits and refrigerant pressures. Temperature and alarm status are indicated on the front panel. It also records the maximum and minimum temperature limits within the enclosure.
The controller includes a compressor anti short-cycle time delay for compressor protection. A bypass time delay prevents nuisance trip outs caused by cold weather start ups and transient high temperature limits.
If any of the critical control parameters exceed limits, the compressor is turned off, an alarm condition is indicated on the front panel. If the preset temperature limits are exceeded, the compressor continues to operate but there is a temperature limit alarm.
The temperature set point, which is the lower limit of regulation, can be adjusted within specified limits. The temperature turn-on point is set-point plus differential.
NOTE: In high ambient operation (above 115°F) the turn-on temperature should not exceed 100°F/38°C, due to the need for compressor cooling.
The High Temperature alarm can be adjusted to suit customer needs within specified limits.