Relay Question

[David_NC]

As part of my de-soldering station project, I need a relay to switch on the vacuum pump. It's an older Gast model with a 1/6th HP motor that draws 4.2 amps and need some input as to which relay to select. I'm looking at these:

3-32V DC to 24-480V AC 40A Output Single Phase SSR Solid State Relay


30A High Current 12V Contactor Relay


30A High Current / 12V Coil Contactor Relay


I've not used an solid state relay before, but I understand they generate heat. I'll be mounting the relay in a 2-gang junction box, so the box itself can be the heatsink, if that's enough. Otherwise, with the mechanical relays, should a cap be installed across the contacts like on the power switch on an amp? If so, what value?
Thanks for any input or suggestions!

 

[dB happy]

Any of those will work, but they're way overkill. You only need a 10a relay. I doubt that solid state relay will even get warm with a 4.2a motor.

 

[David_NC]

Any of those will work, but they're way overkill. You only need a 10a relay. I doubt that solid state relay will even get warm with a 4.2a motor.

Yeah I know they're rated far higher than 4.2 amps. I figured that since there'd be a good bit of start and stopping, perhaps the higher rated ones would hold up better (especially since they're likely not of the quality I'm accustomed to i.e good ol' 'Made in USA' stuff). I wasn't sure about the starting amps. but they'll be pretty low too. I'll go with the SSR just for fun. Thanks.