secondary voltage

[ILCML]

I want to be able to provide 24vac to a circuit from a 208/220/230/240 input (either/or). I cannot find a non-custom transformer that will accept all these inputs...I know I can get away using say the one spec'd for 240, but my 24v becomes 21v. Conversely, a 208v rating will get me ~28v...I've based my theory on the p/s turns ratio using the voltage values then keeping that ratio constant and applying it to the lower/higher input voltage. I would like to maintain a 24vac output with a tolerance of no more than 5% if possible.

The problem I guess, is the fact that this 24vac is fed into an already designed (nonmodifiable) pcb so I cannot alter the 2Xvac once it's generated. Any suggestions?

 

[resqcapt19]

I have seen transformers with a 208/240/277 volt primary in HVAC equipment. That would keep you close to the 5%. Here is one such transformer.

http://www.foster-transformer.com/multi-tap.html#class2

Don

 

[ILCML]

thanks Don! Not sure how I missed that one...