Red Seal Electrician Practice
Signalling and communicationQuestion 116 of 1506

A 4-20 mA level transmitter reads 12 mA. What is the tank level, if 4 mA is 0% and 20 mA is 100%?

  1. 60%
  2. 50%
  3. 75%
  4. 12%
Show answer

Correct answer: 50%

(12 - 4) / (20 - 4) = 8 / 16 = 50%.

Source: Lessons in Electric Circuits IV: Digital (Kuphaldt), 14.1: Introduction to Digital Communication

Practice signalling and communication

Questions last reviewed: 18 October 2026