I'm trying to learn more about transformers that are failing. From my understanding transformers create heat. From too much load or current on the secondary side of a step-down transformer, the heat can damage the insulation and cause a short on some of the secondary side turns.
Now that we have a short in one or a few of the windings. How does the transformer behave under normal rated conditions? Say the secondary had 90 turns and now has 88 turns from two shorts. It seems the transformer should almost behave the same as when it had 90 windings. This is the part I think I'm wrong. Do the shorted windings increase current heat loss? Do the shorted windings increase eddy current/hysteresis loss? Or do the two shorted windings have really minimal effect?
If it is true that a few shorts can have large negative effects, they would cause more heat and could potentially lead to more insulation damage? My other assumption is that extra heat from the damaged secondary would be noticed in a decrease of output voltage because the transformer is getting very hot then its internal resistance will increase.