Maker Pro
Maker Pro

Surge/noise suppression

Hey all. I'm dealing with a piece of old equipment operating with modern technology. I have a stamping press with 1970's controls (lots of AB relays and such). I have added some new modern electronics to aid our process and the noise from the clicking relays are raising hell with the controls memory. The relay control voltage is 120V AC. What would be a good proper size pick for a MOV across the coil terminals on the relays. I usually purchase from Mouser or Newark. Any help would be greatly appreciated.
 
I'd figure that the smallest size would do, with a 150V AC rating.

There's also an arc suppression method using a capacitor and a resistor in series, placed across contacts & coils. Maybe something like 100nF & 100 ohms.
I've seen both incorporated in one component.
 
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