In transformer winding connections, if a secondary lead is taken from the exact midpoint of the secondary winding (not from an end), what is this configuration called?

Introduction / Context:
Transformer secondaries may provide more than one output voltage. A common method is to bring out a lead from the midpoint of the secondary so two equal voltages (with opposite polarities referenced to the center point) are available. This is widely used in dual-rail rectifier supplies.

Given Data / Assumptions:

• The connection is made to the middle of a single continuous secondary winding.
• The point is exactly halfway (ideally) in terms of turns.
• We are naming the configuration, not the rectifier topology.

Concept / Approach:
When the secondary has a lead brought out from its midpoint, the winding is described as center-tapped. With an AC source, the two half-windings provide equal and opposite instantaneous voltages relative to the center tap. This arrangement is ideal for full-wave rectifiers using two diodes to create a dual-polarity supply.

Step-by-Step Solution:
Recognize the physical lead-out: a connection at the winding’s midpoint.Translate to terminology: this is a center tap.Derive the name for the secondary: center-tapped secondary.Confirm that equal half-winding voltages exist relative to the tap.

Verification / Alternative check:
Measure with a voltmeter: the end-to-end RMS voltage equals twice the end-to-center RMS voltage, confirming a midpoint connection.

Why Other Options Are Wrong:
Multiple-tapped secondary implies several taps at various turn counts, not just the center.

Multiple winding secondary suggests physically separate windings.

Single winding secondary is true but incomplete; the defining feature is the center tap.

Split-phase autotransformer: a different device class sharing a single winding between primary and secondary.

Common Pitfalls:
Confusing a center tap with a generic tap. Only the exact midpoint yields two equal voltages.

Final Answer:
center-tapped secondary