Control unit, ventilation fan, MCC (220a)
Control unit, ventilation fan, MCC (220a) |
Location |
Control unit, ventilation fan, MCC (220a) .
Main function |
The control unit controls ventilation fan motor speed with input from the MCC unit.
Type |
The control unit contains electronics which receive and process the MCC unit's control signal regarding fan speed. The control unit grounds the ventilation fan motor and controls fan speed by increasing or decreasing the power supply.
Connection |
The control unit has one connector which is connected to the MCC unit and two separate outputs for ventilation fan motor power supply and ground.
Four pin connector.
Control unit B+ feed to pin 1 from fuse 23 (fuse board 22) and ground connection through pin 3 on grounding point G41.
From MCC unit pin 27, fan speed is controlled by control unit pin 2 with 0-5 volts.
The ventilation fan motor is connected with 2 separate inputs from the control unit.
The fan motor is connected to ground on pin 2 through the fan motor control unit on grounding point G41.
The fan motor receives current on pin 1 and the speed is controlled by the control unit through an increase or decrease of the power supply.
Wiring diagram, control signal.
Wiring diagram, power supply.