Heavy copper windings from transformers

Except the figure is fifteen cents a pound, not twenty five. And for that, #2 gets my nod.

-- Shake off all the fears of servile prejudices, under which weak minds are servilely crouched. Fix reason firmly in her seat, and call on her tribunal for every fact, every opinion. Question with boldness even the existence of a God; because, if there be one, he must more approve of the homage of reason than that of blindfolded fear. -- Thomas Jefferson

Chances are its Formvar or the equivalent, that's a really tough baked- on lacquer/varnish and no solvent likely to shift it in the short term. You might try a segment and some aircraft paint stripper just to see. Probably the difference in price between #1 and #2 isn't going to offset your time and solvent costs.

Too bad nobody needed it, that was a pretty spendy power conditioner. It was probably on some minicomputer installation and those are deader than a dodo these days. Had one that was about 4' on a side running a Tandem back in the stone age at the shipyard. A multi-kilobuck installation, even without the gummint electricians installing it on overtime.

If it's old enough, those oil-filled capacitors may be a problem for you, PCBs were used in a lot of old ones, made a dandy dielectric. Too bad about the stuff being hazardous waste. Have to watch that with all old oil-filled electrical scrap.

Stan

Yep, this is my conclusion also.

You are spot on, this stuff is way obsolete. Just not needed any more.

No, they are GE Dielektrols, "NO PCB" is written on all of them.

Depending on size and weight, I might have been able to use it. I run a lot of computers here, and having one big UPS instead of three of various sizes would be a benefit.

Too late now, anyway.

Enjoy, DoN.

It is not a UPS, it is a power conditioner, lots of transformers and capacitors. oil filled run caps. No batteries.

Those old Ferro UPS units are good - but terribly inefficient.

I took one apart years ago, used its cabinet to house my second phase converter. Built like tanks.

Indeed. An unloaded ferroresonant transformer draws ~35% of FLA. They make good heaters....

So, are there better transformers now? What are they called?

Ferroresonant transformers are magnetic flywheels. They take in line voltage, spin up a [physically imaginary] wheel, and the output "shaft" drives the load. They CAN change the voltage [240 in, 120 out...] but that is almost irrelevent.

Their purpose is to smooth out the power feeding the load. If there is a spike on the line, or a drop out, the flywheel keeps the output steady. They can typically bridge a loss of 3-5 full cycles.

They are also short-circuit proof. Short the output & they deliver the rated current, period.

But now, everything likely runs from a switcher supply; and it's cheaper to have that flywheel be in a capacitor.

I learned something completely new today, thanks!

There were better ones (for many purposes -- e.g. more efficient ones) then, too. They are just plain transformers.

The benefit of the ferroresonant ones is that they maintain close to the same output voltage through a fairly wide range of input voltages. The first ones I encountered were branded "Sola" and were just the ferroresonant transformer, without also being a UPS.

The Best "Ferrups" used them to make it easier to maintain the voltage to the load -- and also the cycling of the transformer probably maintained power for a cycle or two while the inverter started -- driving extra windings on the same transformer.

The ferroresonant transformers were least efficient with very little load. Get them up to say around 75% of full load and they are pretty good. (But yes, my three different sized Best UPS' do add significant heat to the room. Nice in winter, nasty in summer. :-)

Enjoy, DoN.