Back biasing off PT ct

[EFK]

I've not seen this question addressed previously, at least I don't think I have: is back biasing off the power transformer center tap to adjust voltage and/or provide sag in any way stressful to the transformer? I am speaking solely of a *resistive* element here, i.e. a power resistor, not a zener.

[Austin]

I would say no but depends on how much load you are adding and if the transformer was already stressed beforehand. A center tap isn't any wimpier than the end taps the way I understand.

[R.G.]

It is exactly the same as the same resistor in series with the + output of the rectifier(s). Electrical things in series can be put in any order with no change to what the things outside the chain sees.

And putting a resistor in series with the load on a transformer in general lowers the apparent load and is easier on the transformer; although it will not be remarkably different in this case.