The transformer winding to which the incoming power line is connected is called the

The transformer winding to which the incoming power line is connected is called the

• A. Primary
• B. Secondary
• C. Tertiary
• D. Grounding winding

Answer: (A)

The winding connected to the incoming power line is the primary winding. In a transformer, the primary is the coil that first receives the AC voltage from the source and creates a changing magnetic flux in the core. This changing flux induces voltage in the secondary winding (and any other windings) proportional to the turns ratio, providing the transformed voltage to the load. The secondary supplies the output, the tertiary (if present) can serve auxiliary purposes, and grounding is not a normal winding used to carry the input power. So the input-side winding is the primary.

The winding connected to the incoming power line is the primary winding. In a transformer, the primary is the coil that first receives the AC voltage from the source and creates a changing magnetic flux in the core. This changing flux induces voltage in the secondary winding (and any other windings) proportional to the turns ratio, providing the transformed voltage to the load. The secondary supplies the output, the tertiary (if present) can serve auxiliary purposes, and grounding is not a normal winding used to carry the input power. So the input-side winding is the primary.