Control electronics for car air conditioning systems
The ventilation power of a car A/C system is adjusted by a device that controls the blower speed.
Two types of adjustment devices are used in car air conditioning systems.
The system architecture determines the type of control device:
- Passive resistive devices contain two or three resistors corresponding to three or four speeds to adjust ventilation power in stages. The resistors are made of wire coils or fitted to a ceramic frame
- Power transistors enable a continuous adjustment of the air conditioning system