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Relay contact cleaning

Relay contact cleaning

Relay contact cleaning

(OP)
Hello, I've heard that a capacitor placed parallel on the contacts of a two poles relay help them to stay clean. My question is what should be the value of such capacitor? The maximum voltage is 253Vac, so the capacitor should be a X1 type (because there is no fuse to protect the system).
Thanks already for the feebdack.

RE: Relay contact cleaning

I am not sure about that capacitor in parallel you are mentioning, but maybe you are referring to a snubber circuit ?
If you are switching inductive loads, then a snubber circuit is used to soak up some of the inductive kickback, thereby reducing sparking at the relay contacts.
It's usually just a resistor and capacitor in series, but the values have to be roughly adjusted to the load. Alternativly, a high-voltage transorb could do the trick.

RE: Relay contact cleaning

(OP)
I'm not referring to a snubber circuit. My problem is that the relay I use (and I can not change it)needs minimum 12V and 100mA on its contacts to work properly. It is a Schrack (Tyco Electronics) RT31L12. I use the change over contact to know if the relay is ON or OFF. OK now back to my problem, 100mA at 253Vac is 25.3 W !!!
So I need a system which is powerless or poor in power.
I already find a Supertex IC the SR03 and SR05 but I also have place problems. The place I have is between the power pins and the pins of the relay coil minus 5.6mm for the security. The norms are very strong.

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