Mains Transient Supression

"Simon"

Does the device already exist or is it being designed ??

This arrangement inherently clips incoming spikes to the voltage level of the filter cap - something no MOV across the AC can achieve.

........ Phil

Use a 230 VAC isolating power transformer. Use very well rated components with plenty of voltage margin. A mains filter block will probably prove useful. Consider how you ground your device.

I would be more concerned with inputs and outputs - I assume the device doesn't run without some sort of sensors or outputs?

Are you actually experiencing any problems with this device at the moment or are you anticipating that you will be? If you are currently experiencing problems it would be helpful if you could describe the type of problems you are having since the solution will depend to some extent on this information.

Hello Simon,

If possible, place the MOV at the secundary side of the transformer. The size of the MOV (the power it can handle) determines the level of protection. Note that the voltage across the MOV will still rise significantly, so the rest of the circuit must be capable of withstanding that. Look at the max voltage the rectifier bridge can handle.

-- A.J. Kool Elektronica ontwerp Meetapparaat ontwerp

"A.J. Kool"

Mr Kool is a red HOT idiot.

........ Phil