The P215DP Controller is designed for speed variation of single phase motors, especially for fan speed control on air cooled condensers. Head pressure control of a refrigeration system, through speed variation of the fan on an air-cooled condenser, results in optimum performance throughout the year. Using a pressure transducer as the input device to the fan speed controller, gives the most direct and fastest response to pressure variations in the refrigeration system. The controller varies the supply voltage to the motor from 45% to at least 95% over the proportional band using the phase cutting principle.
If the pressure drops below the adjusted setpoint minus the proportional band, the output to the motor is zero volt or the adjusted minute speed setting. This provides speed variation of permanent split capacitor or shaded pole motors which do not draw more than 8 A (rms) full load current.