Full-range input, 120V output UPS

[Behemot]

Not sure if it's the right section, but it's not about repair…

Customer would like what basically is an on-line UPS with full-range input and 120V 60Hz output. Frequency/voltage converter as he put it which is also battery backuped will be almost impossible to get so I have been looking after UPS only.

What was my surprise that the cheap morons produce just full-range 230V output, but not 120V output UPS. Plus there is usually some auto-detect crap for frequency - I need 60 Hz no matter what goes inside. Any tip?

[stj]

Re: Full-range input, 120V output UPS

you need a 2 stage design.
first a buck/boost supply to create a dc voltage of say - 60v, then an invertor to get the output.

you can get chinese buck/boost circuits, but what input range??

[Behemot]

Re: Full-range input, 120V output UPS

No, I need on-line UPS with buck/boost controller. Ordinary ones have boost controller, but I don't think its that complicated to make it run buck/boost, almost all the things are already there.

If it is say 120V nominal, than it is boosted to higher voltage anyway, and only than a clean 120V nominal sine-wave is created. The only difference is it most likely boost to something like 200 V from which it switches 120VRMS sine-wave. All I need is for the inverter to be able to work with 315 V DC bus.

Don't want any of them stinking chinese crap, from what I've seen most of them are PoS. Even if it has sine-wave, which usually does not, it is made in strange design. Just got an inverter which I'll post here soon, it is basically 8 parallel-driven inverters together. How surprising it failed…

I think them US boys may know about something since this voltage is what they use.