Red Seal Electrician Practice
TransformersQuestion 401 of 1506

A transformer in a doorbell or control circuit changes 120 V AC to 24 V AC. What kind of transformer is this?

  1. A step-down transformer
  2. A step-up transformer
  3. An isolation transformer with no ratio
  4. A DC supply
Show answer

Correct answer: A step-down transformer

The output voltage is lower than the input voltage.

Source: Electrical Fundamentals Competency (Industry Training Authority of BC), 5.7: Transformers

Practice transformers

Questions last reviewed: 18 October 2026