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cathoderay57 · 9th Oct 2018, 9:18 am

Hello,

I have built a timer circuit that switches a miniature 12v relay (RS Components 793-3777). The relay contacts are turning a 230v AC motor on and off. The relay contacts are rated at 10A whereas the motor is drawing a steady state load of less than 0.5A as measured on the AC range of a multimeter. Question is, bearing in mind this is an inductive load, is it worthwhile putting a suppressor capacitor with series resistor across the relay contacts? With a purely resistive load I wouldn't bother but with an inductive load I thought it prudent to seek advice. The RS datasheet recommends use of a diode suppressor for DC13 loads but is silent on other loads. I do not know precisely what type of motor so I can only deduce it is in the AC-7A or AC-7B load category. Cheers, Jerry

9th Oct 2018, 9:18 am	#1
cathoderay57 Nonode Join Date: Oct 2017 Location: Bristol, UK. Posts: 2,384	Miniature relay Suppressor Hello, I have built a timer circuit that switches a miniature 12v relay (RS Components 793-3777). The relay contacts are turning a 230v AC motor on and off. The relay contacts are rated at 10A whereas the motor is drawing a steady state load of less than 0.5A as measured on the AC range of a multimeter. Question is, bearing in mind this is an inductive load, is it worthwhile putting a suppressor capacitor with series resistor across the relay contacts? With a purely resistive load I wouldn't bother but with an inductive load I thought it prudent to seek advice. The RS datasheet recommends use of a diode suppressor for DC13 loads but is silent on other loads. I do not know precisely what type of motor so I can only deduce it is in the AC-7A or AC-7B load category. Cheers, Jerry