What is a common tool used by maintenance technicians for measuring electrical voltage?

A multimeter is an essential tool used by maintenance technicians for measuring electrical voltage. It is versatile and allows technicians to measure not only voltage but also current and resistance in electrical circuits. The multimeter can be set to different functions, allowing for accurate readings in various scenarios, including AC and DC voltage measurements, which are critical for diagnosing and troubleshooting electrical systems.

The other tools listed, while useful for various tasks, do not serve the specific function of measuring voltage. A wrench is primarily used for gripping and turning nuts and bolts, a screwdriver is used for driving screws, and pliers are used for gripping, twisting, or cutting wires. Thus, these tools do not provide the capability to make electrical measurements, making the multimeter the correct and most suitable choice in this context.