A multimeter is the most commonly used testing equipment for measuring electrical voltage due to its versatility and ease of use. It can measure both direct current (DC) and alternating current (AC) voltage, making it an essential tool for electricians and technicians. The multimeter typically has settings that allow the user to select the type of voltage to be measured and provides a digital or analog readout, offering accurate voltage measurements across a range of applications, from household circuits to industrial systems.
An oscilloscope, while capable of visualizing voltage changes over time, is more specialized for observing waveforms rather than providing simple voltage measurements. A frequency meter is designed specifically to measure the frequency of electrical signals, not voltage. A current clamp, on the other hand, is used to measure electrical current by clamping around a conductor and does not measure voltage directly.