How do you drive the contactor at present??

Is the coil of contactor AC??

A more detailed reply on your driving circuit will help me help you better.


You have said you observed your supply dipping down to 2V. The MOC3041 are zero cross opto triac drivers and help with getting isolation in between triac and your micro and triggers your triac only when your AC cycle is close to zero this reduces dv/dt at switching and reduces noise generation and help with noise related problem solving. But in your case supplies goes down to 2V this is certainly not a noise problem caused due to firing being random. It has more to do with your power supply stuff and nothing else. Using MOC3041 may not solve your current problem but will surely help you with any possible noise hit.

I would suggest you to use micro port pin ->transistor for buffering such as BC557 -> MOC3041 -> Triac -> Load || snubber || MOV.

Regards,
Prahlad Purohit