Is MOV from L/N to PE safe?

[TimNJ]

You say internal circuitry gets fried...like what exactly? Part of the power supply? The "actual product"?

If you have a PFC front end in particular, maybe a "bypass surge diode" wold help? basically bypass the PFC inductor and boost diode with an ultra fast rectifier. This probably does not address your problem, though.

https://www.powersystemsdesign.com/images/articles/1519761954_Figure%2003.jpg

[CopperCone]

I think that if you add a gdt in series with the mov you have a longer responce time.

Hence the speed-up capacitor.

Yes but regardless of how fast you can get the gdt to fire it is still much slower then the mov, so the circuit could get whacked

My recomendation is parallel movs with kapton tape and a thermalfuse. This ishow its typically handled in better power strips and such.

Then you can protect your mov by putting a gdt and a impedance between the mov and the gdt to ensure proper firing sequence.