Red Seal Electrician Practice
TransformersQuestion 1111 of 1506

Which regulation figure shows the best power transformer?

  1. 6 percent
  2. 9 percent
  3. 15 percent
  4. 2 percent
Show answer

Correct answer: 2 percent

A lower percentage means more stable secondary voltage. A good power transformer is below 3 percent on a resistive load.

Source: Lessons in Electric Circuits II: AC (Kuphaldt), 10.6: Voltage Regulation

Practice transformers

Questions last reviewed: 18 October 2026