Recommendations for isolated variable AC power supply?

[MRiddickW]

Hi all, does anyone have a recommendation for an isolated variable AC power supply? I'm working on a project and I may need one soon.

Minimum requirements:

• 80 VAC to 280 VAC output
• 2 A at 120 V (I guess)
• 50 Hz and 60 Hz
• Less than $1000. The closer to $500 the better

I have no shame in buying used or off eBay, as long as I can feel reasonably comfortable using it. I checked Rigol and Siglent, but neither of them seem to make AC power supplies.

If there's a big jump in quality from say $500 to $700, that may be doable; if all goes well, someone else will buy this for me, but I suspect their budget will top out around $500, so I might could bankroll the rest if it feels worth it.

Thanks!

[eevcandies]

How about a big variac and an isolation transformer?

Do you need to create a different freq than the one you have?

I have an Elgar EW801  I bought on the bay..very nice, but no isolation (could run it off a big isolation transformer)...you can create about any voltage & any AC freq you want, up to 800 watts.   I use it to make a clock spin faster, at 90 Hz

[rdsi]

How about a big variac and an isolation transformer?

This is what I do.

The box below the variac contains 2 transformers with various taps for my purposes.  You can easily mix & match either the variac and/or isolation transformer to get whatever you need for under $500.

I put this together like 30 years ago & it still works fine...

Needles to say if you're going to be outputting 280 VAC I would give some thought about safety - maybe the newer sheathed bananas!

[MRiddickW]

Thanks all, good to know!

Do you need to create a different freq than the one you have?

I'm in the US, so I'm on 120 VAC 60 Hz. The project will need to also work at 240 VAC 50 Hz, but I suppose it's also easy enough to make sure the filter caps are big enough and just not worry about it. That requirement was written with the mindset of "If I'm going to buy a commercial product, I'm going to make sure it does everything I expect to need for this and future projects."

Since I need the higher voltages than 120 V, I'll have to make sure something in there is a step-up transformer as well, I suppose.

Yeah, the voltages definitely scare me. Not quite tube amp level, but I suspect the difference is not enough to matter all that much.  Even more than getting the range of voltages I want, I guess the possibility of current limiting is what really got my mind going about a commercial product. What would you recommend as a fairly straightforward adjustable current limiter? I don't mind getting my hands dirty to get this box together, I just need to avoid my penchant for turning things into a Capital-P-Project.