Re: modding a 24V PSU to 12V
You could feed the unit with 120Vac from a suitable autotransformer to deal with the excess passbank voltage issue. You may need to retap the input for 220V to retain a similar passbank Vce. Whether the control circuits will be happy at around half their normal supply voltage would be a matter for experiment- you might need to incorporate an extra small supply to deal with this.
Alternatively and depending on its physical construction, you may be able to remove secondary turns from the mains transformer to get down to the voltage you need. Same caveat about control supplies.
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