What type of voltmeter is specifically designed for high voltage cables?

The choice indicating contact voltmeters as the correct answer is rooted in their design and functionality. Contact voltmeters are specifically engineered to measure voltage in electrical systems, including high voltage cables, by establishing a direct connection to the electrical circuit. This direct contact allows for accurate measurements, which is critical when dealing with high voltage scenarios where precision is paramount.

Contact voltmeters typically come equipped with insulated probes that can safely handle high voltage levels while minimizing the risk of electrical shock to the user, making them suitable for tasks involving high voltage cables. They also often include features that enhance safety and facilitate reliable readings under such conditions.

While non-contact voltmeters can measure voltage levels without the need for direct contact, their effectiveness can be limited when dealing with very high voltages, as they may not provide the same level of accuracy as contact types. Piezo voltmeters, on the other hand, operate on different principles and are not specifically designed for high voltage applications, focusing more on certain types of measurements based on pressure or changes in materials.

Therefore, selecting a contact voltmeter for high voltage cable assessment ensures both safety and measurement reliability.