Centered Tapped Transformer 18-0-18
A center-tapped transformer also known as two phase three wire transformer is normally used for rectifier circuits. When a digital project has to work with AC mains a transformer is used to step-down the voltage and then convert it to DC by using a rectifier circuit. In a center-tapped transformer the peak inverse voltage is twice as in bridge rectifier hence 18-0-18 center-tapped transformer is commonly used in full wave rectifier circuits. Schematic representation is as shown below
When an alternating current is supplied to the primary winding of the transformer it creates a magnetic flux in the core, and when the secondary winding is brought near, an alternating magnetic flux is also induced in the secondary winding as the flux flows through the ferromagnetic iron core and changes its direction with each and every cycle of the alternating current. In this way an alternating current also flows through the two halves of the secondary winding of the transformer and flows to the external circuit.
The two voltages, between line 1 and neutral and between neutral and line 2 can be named as VA and VB respectively. Then the mathematical relation of these two voltages shows that they are dependent upon the primary voltage as well as the turn ration of the transformer.
VA = (NA / NP) * VP
VB = (NB / NP) * VP
One thing that should be noted here is that both the outputs VA and VB respectively are equal in magnitude but opposite in direction, which means that they are 180 degrees out of phase with each other. For this purpose, we also use a full wave rectifier with a center tapped transformer, to make both the voltages in phase with each other.
12-0-12 Variance Centered tapped transformer is also available for different applications
- Step-down 18-0-18 Center Tapped Transformer
- Input Voltage : 220V AC at 50Hz
- Output Voltage : 18V or 0V
- Output Current : 1A
- Low cost and small package
- Rectifier circuits
- AC-AC step down
- Full wave rectifier
1 x 18-0-18 Centered Tapped Transformer