Why is the transformer used in a rectifier circuit?
The transformer in a rectifier power supply circuit serves several purposes.
1- used to change the voltage level from the 115VAC to another level, either higher of lower, to accomadate the needs of the rest of the circuit.
2- provides isolation between the power mains and the circuit power for safety reasons. If you touch a hot part of the circuit on the secondary side of the transformer while being grounded, you most likely will not get a shock. If the transformer wasn’t in the circuit….you wouldn’t be so lucky. Other than very small leakage currents, no current flow’s from the primary side of the transformer to the secondary.
3- Some rectifier circuits require a center reference point. This is easy to do with a center tapped transformer winding.
4- Many devices require multiple voltage sources. A transformer can have multiple secondary windings, each wound to produce a different voltage. An example would be in the tube circuit, where the filaments of a tube might require
