How does a Center Tap really works?

[Gauthier]

Does this schematic is right?

If yes tell me how in that schematic: the C.T. can be use as a 0V reference voltage.

It's really confusing me, there's not suppose to be voltage on the C.T. if my first draw is good?

thanks

Gauthier

 

[BradtheRad]

Schematic #1.

Uses the transformer's secondary coils at a 50% duty rate. Current goes through one half of the secondary at a time.

It's less likely to overheat. And it has a low parts count. However it is not the most efficient use of a transformer.

Schematic #2.

Uses the transformer secondary at 100% duty rate. Current goes through the entire secondary coil on each half of the AC power cycle.

The center tap is there in case a return path for current is needed. Which is to say, the c.t. carries current only: (a) if loads are unequal, or (b) if a load is absent on either side.

 

[permute]

Voltage is relative. when we label a node "0V", it is done to make analysis easier. after all, the node could also be labeled "1000V", with other nodes being "1005V" and "995V" instead of "5V" and "-5V".

the 0, 6, 12 markings are done to indicate how the windings are configured -- the 0V here is again just an opinion. you can call any of the terminals 0V as long as you re-label the others (-6 0 6) or (-12 -6 0).

 

[Gauthier]

Thanks guys !