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Well done Bob for taking the effort to look in to the topic of mains related protection. Going above and beyond the simplest form of transient over-voltage protection by a MOV starts to get pretty onerous - as indicated by some types of commercial gear that has that aim, which can deploy series devices (such as fuses, thermistors, inductors) to work with a MOV to achieve a desired protection level for a specific standardised mains event. Without a series element in the line, the ability to protect from a long duration over-voltage event may become mute. I'm not sure if that is what you are referring to, or whether your comment was related to staggered type protection where an upstream type of protection coordinates with your equipment protection. Anyway, it all gets pretty onerous to implement extra protection for a commercial/industrial situation, let alone a private/domestic situation. It certainly is an interesting topic to appreciate, and to see how expert companies go about deploying extra protection.
Having a 2 pole mains switch would switch out a neutral-to-earth MOV, but is not per se needed for the active-to-neutral or active-to-earth MOVs.
With respect to MOV selection, I couldn't see any problem with your choices, as their nominal AC, and DC ratings appear to safely exceed the nominal working voltage levels. Sorry for not making that comment earlier.
Ciao, Tim
Having a 2 pole mains switch would switch out a neutral-to-earth MOV, but is not per se needed for the active-to-neutral or active-to-earth MOVs.
With respect to MOV selection, I couldn't see any problem with your choices, as their nominal AC, and DC ratings appear to safely exceed the nominal working voltage levels. Sorry for not making that comment earlier.
Ciao, Tim
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