220v surge protection - how?

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Kona, Hawaii

I have an expensive, microchip controlled woodworking lathe that I'm converting from 110v to 220v. Since there are sensitive electronics on board, the manufacturer recommends (in fact demands for warranty) using a surge protector, an idea I find sensible. This is no problem on 110v or on industrial/euro style single ended 220v (220 line to neutral).

However this is on US residential, split phase (220 line to line), the machine then having no neutral (grounded mid point conductor).

Before I cognized that I had a dilemma, I was planning to build really good protection with a ZeroSurge brand OEM (no housing, wire yourself) surge protector. This is a series mode, inductor type surge protector, but is only available for single ended single phase (in either 110 or 220 ratings). It routes the (reduced) surge power to the neutral line, as opposed to the ground as in most surge protectors (a whole separate debate!).

What is the best way to surge protect this machine?

My not-thought-all-the-way-through idea at the moment involves two separate ZeroSurge type protectors, one on each hot line (and each needing to be rated for only 110v and about half the machine's current draw), with a conductor provided from the neutral terminals of the protectors back to the neutral bus in the load center (this would be a dedicated circuit). Am I wacked?

I don't consider myself an expert, so I humbly request the guidance of the highly knowledgeable, of which there are obviously some here. Thanks!



Staff member
Sanaka, this is not a DIY forum, the rules here prohibit us giving advice to those outside the electrical trade.

My suggestion is hire a licensed electrical contractor.
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