Currently i'm experimenting with 12VDC energy meters latching relays and at least for me the feature of detecting status of contacts ( required by some clients ) which is built in as in the diagram below is quite interesting. Now i need to interface it to a microcontroller safely. At the top of my head i may think of using an optocoupler but my understanding is i need to isolate the grounds ? thus making the design a bit pain in the kneck, is this the only feasible method or are there other approaches ?. enter image description here
TL;DR pins 4 and 5 switch on / off depeding on status of relay, how do i sense/ measure status of the latch with those pins?