leonardo0
Junior Member level 3
220 to optocoupler
Hi
I need to design a circuit to read ,measure the 220 V mains voltage.
I saw one design note where the author was using one 150 V zener plus one resistor to limit current to the optocoupler .Mains voltage was measured by measuring the period the output from the optocoupler was low during the positive semi-period . He also had a diode to protect from reverse biasing the input emmiting diode . I imagine that during the negative semi-period the current would flow from the protection circuit so i see power issues .Has anybody experienece and can give me a simple solution or any schematics etc?
Hi
I need to design a circuit to read ,measure the 220 V mains voltage.
I saw one design note where the author was using one 150 V zener plus one resistor to limit current to the optocoupler .Mains voltage was measured by measuring the period the output from the optocoupler was low during the positive semi-period . He also had a diode to protect from reverse biasing the input emmiting diode . I imagine that during the negative semi-period the current would flow from the protection circuit so i see power issues .Has anybody experienece and can give me a simple solution or any schematics etc?