Application of Electronic Controls to On-Off Fan Drives and Air Conditioning Systems

The application of electronic controls to on-off fan drives and air conditioning systems offers improved operating efficiencies, extended component life, easier troubleshooting and reduced maintenance costs for trucks and buses. This paper describes the differences between the traditional control systems which rely on mechanical temperature and pressure switches and recently developed control systems which incorporate the use of electronic logic circuitry. A recently introduced on-off fan drive control system is discussed in detail. Also described is an advanced air conditioning control system currently being field tested.