I am working on controlling a 220V 0.75hp AC motor with a Relay, and came across HFE9-3/12DST which by design is a dual coil, latching relay BUT with contacts in NC position.
I was wondering since latching holds on indefinitely until power is applied to opposite coil, would NO/NC settings compromise the safety/control of motor, ie I could setup the Relay in NO position, and keep it that way, until I need to move in the NC position, knowing that even if power is down, the Relay will not switch.
Additionally, I have the snubber circuit on the AC side for relay arc prevention when motor is turned off, and flyback protection circuit on the DC side when current is withdrawn from the coil. [
datasheet Link : https://www.alldatasheet.com/datasheet-pdf/pdf/660894/HONGFA/HFE9.html?