Gadiya electronics, catering to automation needs manufactures zero speed switch based on microcontrollers which gives signal when monitored speed drops to zero. This switches are non-contact type unit and uses proximity sensor for sensing the speed and has an enable input. The zero speed switch scans for speed when it recieves the signal. When the speed drops to zero and output [potential free] is energised it can be applied for tripping the system or giving warning signal. The zero speed switch are also provided with multiple outputs on request. The zero speed can be actually zero or some preset minimum allowable speed. The unit also acts as an rpm indicator unit displaying the current speed and can function also on 230 v ac and has battery back-up to store set speed and number of pulses per rotation.
