How to Use a Non-Contact Voltage Tester Wisely

A non-contact tester is useful for an initial indication of AC voltage, but it is not a complete proof of de-energization.

What matters

• Verify the tester on a known live source before and after use.
• Understand the tester's specified voltage range and limitations.
• Treat unexpected or ambiguous indications cautiously.
• Use the verification method required by your electrical-safety procedure.

How to think about the job

Non-contact testers detect an electric field and can be useful for quick screening. Their indication can be affected by shielding, cable construction, distance, and induced voltage. For safety-critical verification, follow the required test method and use appropriately rated equipment.

Before you buy

Match the tool to the equipment, fastener, environment, and manufacturer's requirements. Specifications and included accessories can change, so confirm the current product listing before ordering.