The D'Arsonval–Weston meter movement uses a moving coil which carries a pointer and rotates on pivots or a taut band ligament. These galvanometers were bulky and delicate. While useful in the lab, the devices were very slow and impractical in the field. These were used to measure resistance and voltage by using a Wheatstone bridge, and comparing the unknown quantity to a reference voltage or resistance. The first moving-pointer current-detecting device was the galvanometer in 1820. Cheap multimeters can cost under US$10, while laboratory-grade models with certified calibration can cost over US$5,000.ġ920s pocket multimeter Precursors
DIGITAL VOLT METER PORTABLE
They can be portable handheld devices or highly-precise bench instruments.
Multimeters vary in size, features, and price. Digital multimeters (DMMs) have numeric displays and have made analog multimeters virtually obsolete as they are cheaper, more precise, and more physically robust than analog multimeters. Īnalog multimeters use a microammeter with a moving pointer to display readings. The first attested usage of the word "multimeter" listed by the Oxford English Dictionary is from 1907. Some feature the measurement of additional properties such as temperature and capacitance. A typical multimeter can measure voltage, resistance, and current, in which case can be used as a voltmeter, ammeter, and ohmmeter. A multimeter (also known as a volt-ohm-milliammeter, volt-ohmmeter or VOM) is a measuring instrument that can measure multiple electrical properties.
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