I'm looking to use a (surplus, NOS) Sola (catalog number 22212) ferroresonant voltage regulating transformer (120V primary and secondary) as a low-power isolation transformer (4A) in case I need to float some project. Will this work? What safety issues would I run into vs. using a designed-for-purpose isolation transformer?
It will work, and there shouldn't be any safety issues.
Just be aware:
- Ferroresonant transformers are horribly inefficient, so the input power will be considerably higher than the output power. (i.e., they get hot!)
- The output waveform is more like a square wave than a sine wave.
- The input power factor is horrendous.
These characteristics occur because the core is deliberately driven into saturation by the resonant winding in order to get the voltage-regulating effect.