Which device can indicate the presence of voltage without direct contact?

• A. Multimeter
• B. Clamp meter
• C. Non-contact voltage tester
• D. Insulation resistance tester

Answer: (C)

The device that can indicate the presence of voltage without direct contact is a non-contact voltage tester. This tool is designed specifically to detect the presence of electrical voltage by sensing the electric field generated by the voltage in an insulated wire or component.

When the non-contact voltage tester is brought close to a live conductor, it lights up or sounds an alarm if voltage is present, without the need to touch the wire itself. This feature makes it an essential and safe tool for electricians and maintenance personnel, allowing them to quickly verify whether a circuit is energized before performing any work.

In contrast, while a multimeter can measure voltage, it requires direct contact with the circuit by connecting its leads to the circuit points. Similarly, a clamp meter is used to measure the current flowing through a conductor and needs to clamp around the wire, thus requiring a physical connection as well. An insulation resistance tester also requires connection to the circuit components to assess the insulation quality and cannot detect voltage without making contact. Therefore, the non-contact voltage tester stands out as the only device that effectively indicates voltage presence without direct contact.