Optocoupler Isolation Circuits for Industrial Application Optocuploare în Aplicaţii Industriale
Down-link isolation takes a single optocoupler to pass a standard digital signal
Detecting the presence of the mains voltage requires ground isolation Standard LED transmitter in optocouplers cuts half wave of the AC mains-voltage, i.e. optocoupler also rectifies the input voltage
Controlling both pulses of the mains
Low Current Sensing
By-passing the sensor with the optocoupler transmitter allows higher current sensing
Same function for AC voltage detection
Threshold Detector plus Isolated Switch
Overvoltages in mains voltage are common
Voltage Surge
Damped Sinusoidal Voltage Spike is Typical
Current Dividing Allows Level Adjustment
Filtering capacitor smooths possible voltage spikes
Non-dissipative voltage divider saves power
Bi-polar voltage clamp uses dedicated components