SSR AC-motor RC snubber circuit - What type of capacitor to use?

Other Hardware General Electronics
1

Hi!

I am controlling a AC-motor with a SSR.

If I have understood correct I should use a RC snubber circuit to protect the SSR output?

What type of capacitors could I use? High voltage ceramic disc capacitors are expensive and the stores I usually buy from don't have any.

Is it ok to use Mylar capacitors in a RC snubber circuit?

/Olof

2

I wouldn't be so concerned with the sort (mylar, polyprop., ceramic, etc) as much as the rating - over-rate it.
Which sort would depend most on environmental factors.

It's not impossible, but I'd be surprised if your SSR didn't have this incorporated already.

3

Thanks for the answer.

The SSR are one of the common cheap ones on Ebay.

One like this: http://www.ebay.com/itm/Solid-State-Relay-SSR-25DA-25A-3-32VDC-Output-24-380V-AC-Solid-State-Module-/130905531225?pt=LH_DefaultDomain_0&hash=item1e7a93e359

Do you think I can skip the RC snubber circuit?

One more question: If I would use a 0,1uf capacitor and a 100ohm resistor, would it work with a small 0,25W resistor or should I get a bigger one?
The motor is 230V/0.02A.

4

1W, 2W

Two 220? 1/2W in parallel = 110? 1W
Two 50? 1/2W in series = 100? 1W

5

Good idé.
I have som 200R 0,5W resistors that I can wire in parallel.

Thanks again.