When performing resistance measurements, which statement is correct?

When performing resistance measurements, which statement is correct?

• A. Power Must Be Disconnected From The Circuit
• B. The Circuit Can Remain Powered
• C. Higher Resistance Indicates Good Continuity
• D. Resistance Testing Should Be Shorted

Answer: (A)

When you measure resistance, the test instrument injects a small current to determine how much resistance is present. If the circuit is powered, that external voltage can skew the reading, damage the meter, or create a shock hazard. So you must disconnect all power and discharge any stored energy (like capacitors) before taking a resistance measurement. This makes the measurement accurate and safe. Keep in mind that higher resistance does not indicate good continuity—it usually means poor or no continuity. Good continuity is indicated by very low resistance. Also, you should never short parts of a circuit to measure resistance; shorting can bypass components, blow fuses, or cause damage.

When you measure resistance, the test instrument injects a small current to determine how much resistance is present. If the circuit is powered, that external voltage can skew the reading, damage the meter, or create a shock hazard. So you must disconnect all power and discharge any stored energy (like capacitors) before taking a resistance measurement. This makes the measurement accurate and safe.

Keep in mind that higher resistance does not indicate good continuity—it usually means poor or no continuity. Good continuity is indicated by very low resistance. Also, you should never short parts of a circuit to measure resistance; shorting can bypass components, blow fuses, or cause damage.