Digital RPM Tachometer Work with encoder/switch/other signals for measurement of RPM,HZ,line speed, ... waveform pulse(square wave,triangle wave,proximity switch,photo switch or AC voltage)volt signal, contact switch, encoder, etc. Or power frequency(AC 0 ... Proximity Sensor, ,Pressure sensor ,load cell sensor, KNE KSC box, Rotary Encoder and computer integrated control system etc. They are widely used ...