The Frigitek® ECMotor Controller functions by sensing the operational status of the cooling system, and controls the speed of the EC evaporator fans. When the thermostat is satisfied and the compressor cycles off, the Frigitek controller will sense the compressor off cycle and will switch the motors to the slower speed.
Below is an example of the type of the type of savings comparing a three fan motor evaporator unit with standard shaded pole motors to a unit fitted with three (2) speed EC motors and a Frigitek controller.
A look at efficiency:
Before Frigitek 4,370. KWH/yr
After Frigitek 649. KWH/yr
Total Savings 3711. KWH/yr
* An 83% reduction in energy use
It is a fact that all of the electrical power which is used by the fan motors ends up as heat inside the refrigerated space. By operating the fans at a low speed when no cooling is called for, and at high speed only when the system is actively cooling the refrigerator, much less heat is introduced into the refrigerator. Although this results in an additional saving in evaporator fan motor energy consumption, the reduction in fan motor heat generated causes a significant reduction in refrigeration operation, saving enough energy at the compressor to almost double the savings provided by the EC motors alone.
The Controller consists of three major components:
1. Speed Controller 2. Temperature Differential Sensors 3. An Ice Sensor
The ECMotor Controller unit is normally mounted inside the wiring end of the evaporator. Three cables connect the Controller into the evaporator system. One cable is wired to the power connections, one to the Differential Sensors and one to the Ice Sensor.
The Frigitek® ECMotor Controller is designed to be easily installed when upgrading to EC motors. Installation typically takes about 45 minutes (as does each EC Motor), and can be done by any competent electrician or refrigeration technician. In addition to its energy saving qualities, the Frigitek® ECMotor Controller also provides some intrinsic advantages. The low speed of the fans results in lower evaporation from sensitive stored foods, and the lower noise levels contribute to worker efficiency, and a more pleasant workspace.
The Temperature Differential Sensors (TDS) monitor the temperature difference across the evaporator expansion valve. This difference in temperature indicates whether or not refrigerant is flowing through the evaporator. The Controller commands the fans into high speed when refrigerant is flowing, into low speed when it is not.
The Ice Sensor is used to determine if the evaporator has developed an ice buildup. If ice is detected, the fans are operated in high speed until the ice has dissipated. The ice sensor is not used on freezer installations.
The TDS Sensor and the Ice Sensor interconnect cables are low voltage cables and require no conduit. The highest voltage in these cables is 12 volts.
The Low speed for the EC motor is typically 600 RPM, a speed which ECE has determined to provide the best balance between savings and air flow.
