Transformers test 4

Wye wye bank

H2s tie together and go to ground. X1 and X2 are paralleled. All X2s tie together and go to ground/neutral X3s are left idle X1s are hot legs

Wye delta bank

H2s are tied together and float. H1s go to individual phase. X2 on lighter/middle pot go to ground/neutral. Outside X2s are idle. X1 to X3s are tied together. Farthest X3 and farthest X1 are tied together to make the power leg

Power leg

Is 1.5 coils away from neutral and 1.732 times greater than neutral to hot leg. Only exists on delta secondaries

What does floating the H2s do?

To protect the transformer from overloading

Delta Wye bank

H1s and H2s tie together. X3s are left idle. X1 and X2s are paralleled X2s tie together and go to neutral from lighter/middle pot. Each X1 are hot legs

Delta delta bank

H1s and H2s tie together. Each primary bushing on lighter/middle goes to A and B phase and only one outside primary bushing goes to C phase. X2 on lighter/middle pot goes to neutral. Power pot X2s are left idle. X1 and X3s tie together. Farthest X3 ties to farthest X1 to make the power leg. X3 and X1 on lighter pot make hot legs

Lighter pot

X2 is always grounded. Provides the majority of the single phase load. Must be sized larger than the other 2 transformers

Power transformers

They share equal portions of single phase and 3 phase load

Delta secondaries do not allow all three transformers to share single phase load equally

True

X3s are left idle in a ___ secondary

Wye

Power pot X2s are left idle in ____ secondary

Delta