What is a sign of a poor ground path when testing a bus electrical circuit?

• A. Readings are stable and accurate.
• B. Readings become unstable or inaccurate.
• C. Ground path has no effect on measurements.
• D. The ground path is irrelevant to voltage readings.

Answer: (B)

A solid ground path provides a stable reference and a low-resistance return for current. When the ground path is poor, the return current encounters extra resistance, causing voltage drops and noise. This makes the measurement point’s voltage float as load or current changes, so readings become unstable or inaccurate. A good ground would keep readings steady and correct. Therefore, unstable or inaccurate readings signal a poor ground path, while the ideas that ground has no effect or is irrelevant are not true because the ground reference directly influences voltage measurements.