Final answer:
The two general categories of metering devices are analog, which uses a galvanometer, and digital, which utilizes an analog-to-digital converter. Analog meters involve a needled gauge, while digital meters provide numeric readouts.
Step-by-step explanation:
The Two General Categories of Metering Devices
The two general categories of metering devices are analog and digital meters. Analog meters use a galvanometer, which involves a coil of wire that reacts to an electric current in a magnetic field, causing a needle to move across a scale to indicate a measurement. For instance, to measure current, a small resistance known as a shunt is placed parallel to the coil in an analog ammeter, while a high resistance is added in series for an analog voltmeter. On the other hand, digital meters use an analog-to-digital converter (A to D converter) to translate electrical values into numeric data that is then displayed on a screen, similar to that of a handheld calculator.
While analog meters have been largely replaced by digital meters in contemporary practice due to their ease of use and versatile functionality, they still have applications where their specific characteristics are beneficial. Digital meters are favored in most situations for their precision, convenience, and the ability to handle more complex measurements and multitasking as seen in multimeters.