c_mitra
Advanced Member level 6
There is nothing wrong if all the outputs share the same ground. The transformer was made that way such the different windings share one common point. But what I was telling that the input side ground and the output side ground should not be connected directly. We do sometimes connect the two grounds with a small value high voltage capacitor; the basic idea is that the primary and secondary coils should not get a high voltage between them.
As you are handling 500W (max) power, the transformer design (the windings) should be made such that the (i) core does not saturate and (ii) the flux excursion should be approximately symmetrical (current in the primary must flow in both ways).
But for the feedback loop, it is good to use an opto coupler; they will provide the required ground isolation but will provide a signal path (from the output side to the input side).
As you are handling 500W (max) power, the transformer design (the windings) should be made such that the (i) core does not saturate and (ii) the flux excursion should be approximately symmetrical (current in the primary must flow in both ways).
But for the feedback loop, it is good to use an opto coupler; they will provide the required ground isolation but will provide a signal path (from the output side to the input side).