pavlo_y0l0s
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ESP has a nice article talking about RC snubbers over the relay contacts. Even though switch is not a relay but it is similar in operation.
Section 4.2
“There are some 'rules of thumb' that are applied to snubbers used across contacts, and these give the designer a good place to start. The following fall into that category - this isn't meant to be the only range of values that can be used, but you have to start somewhere ...
Section 4.2
“There are some 'rules of thumb' that are applied to snubbers used across contacts, and these give the designer a good place to start. The following fall into that category - this isn't meant to be the only range of values that can be used, but you have to start somewhere ...
For example, if you wanted to switch 48V DC at 10A, R1 could be 24Ω, and C1 would be around 20µF. If AC is being switched, the series impedance of R1 + C1 must be large compared to load impedance, or current will be delivered to the load even when the contacts are open. Because AC is less troublesome than DC, the capacitance value can be reduced considerably, and I'd suggest that C1 would only need to be around 1µF at the most. “R1 - 0.5 to 1Ω per contact volt
C1 - 500nF to 1 µF per contact amp