I've always thought that the only place you'd get a three phase PSU was from an industrial supplier, but it turns out eBay has everything.
This really nice unit is sold as being for a 380V AC supply (two phases of a Chinese 220V supply), but on the manufacturers site it suggests it has a range of up to 528V AC and 746V DC. I'm not sure I'd push it that far though.
The module is clearly made to industrial standards. Really good separation and what appears to be a proper isolated transformer design, with well placed components and a bias towards reliability instead of cost. One particularly nice feature is the output overvoltage safety net of a second simple voltage clamping zener in the feedback circuit, so if the voltage reference fails the output voltage will only go up by a few volts.
This has to be one of the best looking power supplies that I have seen that isn't a prominent brand like Mean Well. It's perhaps notable that this company is called Munpower and has a logo that hints at the Mean Well logo.
Some equipment has two or three phase supplies, but no neutral. That's where this module could be used to provide power to control circuitry. It might also have uses in DC electrical traction equipment. Some extra VDRs/MOVs to clip voltage transients would be useful if doing that.
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