DC Fans Add Special Functions

The company now offers a variety of special functions for its dc fans including tachometer output, locked rotor alarm, PWM inputs, and thermal and constant-speed controls. Tachometer outputs and locked-rotor alarms, available on most of the company’s dc fans, provide an accurate means of monitoring and reporting a fan’s rotational speed as well as triggering of an alarm or indicator if speed falls below a certain RPM. The tachometer-output option is available as either a standard 5V TTL or as an open-collector signal. Thermal speed control employs a thermistor-controlled circuit that increases fan speed only when the temperature rises above a determined set point. Thermistor control circuits can mount directly in the fan hub or remotely via a lead wire. The constant speed function senses variable input voltage, which causes variations in power output and maintains the fan’s constant speed regardless of input voltage fluctuations. Additionally, the company offers both customization and value-added services to meet user requirements. ORION FANS, Dallas, TX. (800) 323-2439.