I'm a digital guy whose forgotten his "big wire" electrical education. I'm surprisingly unable to find a solid reference for this.

I have a (European) 220V 50Hz split phase source (110V + 110V + GND). I have a UPS which only accepts single phase input (220V + N + GND).

How do I go about finding and how do I wire up an isolation transformer to use my UPS?

Update: This is a ship, not residential/commercial EU power. It is indeed split phase. I've also verified (by plugging it in and measuring output) that the UPS does not work and does need a ground potential neutral.

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    \$\begingroup\$ EU don't use split phase, US do. Nothing really matters, both systems would work. \$\endgroup\$ – Marko Buršič Jun 26 '19 at 19:03
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    \$\begingroup\$ Does the UPS datasheet read that the neutral should be at ground potential? I would think it could receive two hots directly -- possibly no need for an isolation transformer. \$\endgroup\$ – C. Lange Jun 26 '19 at 19:18
  • \$\begingroup\$ @Marko Buršič: There are split-phase installations in Europe, e.g. in Spain. \$\endgroup\$ – Janka Jun 26 '19 at 21:31
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    \$\begingroup\$ Does the UPS have a split-phase output? An isolation transformer will easily allow a ground-potential input, but the output probably can not be split-phase. A 220:220 isolation transformer should be easy enough to find and connect. Simply connect the primary to your source and the secondary to the input of your UPS and ground one side. \$\endgroup\$ – Charles Cowie Jun 26 '19 at 21:40

There are various solutions using commercial fixed-wiring power transformers. For example HPS makes this series can be wired the way you want.

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