Meters and troubleshootingQuestion 729 of 1506

What is the purpose of a "live zero" in an instrument signal?

To make the signal digital so that it can be sent over a data network
To reduce the cost of the transmitter and the cable
To raise the signal voltage to 120 V
To tell a true 0 percent reading from a dead or broken system

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Correct answer: To tell a true 0 percent reading from a dead or broken system

If 0 percent is a non-zero signal, a zero signal can only mean a fault.

Source: Lessons in Electric Circuits I: DC (Kuphaldt), 9.1: Analog and Digital Signals

Questions last reviewed: 18 October 2026

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