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I put a 275v MKP capacitor before the transformer, as I assume the kickback will be DC. However it doesn't seem to do anything. It doesn't seem to absorb any current at all.
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I put a 275v MKP capacitor before the transformer, as I assume the kickback will be DC. However it doesn't seem to do anything. It doesn't seem to absorb any current at all.

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You really need to use one of my suggestions. &nbsp;simple capacitor is not sufficient.<br />

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You really need to use one of my suggestions.  simple capacitor is not sufficient.


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I've put a bidirectional TVS and it works now.
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I've put a bidirectional TVS and it works now.

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I have a 220V to 12V 500mA transformer+rectifier plugged into my wall socket, that drives a pair of relays. I've put protection diodes on the relays. However I still have a 500v kickback into the mains when I turn off the power.<br />
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How am I supposed to fix this? Using a varistor/TVS or something? Do I connect it across the mains before the transformer? Can someone suggest a specific part that I should use?
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I have a 220V to 12V 500mA transformer+rectifier plugged into my wall socket, that drives a pair of relays. I've put protection diodes on the relays. However I still have a 500v kickback into the mains when I turn off the power.

How am I supposed to fix this? Using a varistor/TVS or something? Do I connect it across the mains before the transformer? Can someone suggest a specific part that I should use?

Usage of Varistor/Transient Voltage Suppressor ??

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Automotive

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