multimetri

Multimetri, commonly referred to in English as multimeters, are portable instruments used to measure electrical quantities. They combine several measurement functions in a single case and are widely used in electronics, automotive diagnostics, and electrical installations. Typical measurements include DC voltage, AC voltage, DC current, and resistance. Many models also measure continuity, capacitance, frequency, temperature, and diode response. Modern multimetri are digital multimeters (DMMs) that display readings as numerals; analog versions use a moving-coil gauge.

Two main families exist: digital and analog. Digital multimetri (DMMs) can be manual-range or auto-range; auto-range meters select the most appropriate scale automatically. True RMS models measure the effective value of AC waveforms with non-sinusoidal shapes for more accurate readings. Additional features may include data logging, relative measurements, min/max recording, hold functions, and non-contact voltage detection.

Construction and safety: Multimetri typically include distinct input jacks for voltage, current, and other measurements, along with protective fuses and sometimes overload protection. They are powered by batteries. Safety standards assign CAT ratings to indicate suitable environments; improper use on high-energy circuits can cause injury or equipment damage. Use of proper test leads and series resistance when measuring current is recommended.

Applications and history: They are used for troubleshooting in electronics, automotive work, and electrical installations. The first devices combined voltmeter and ammeter functions; the emergence of digital multimeters in the 1970s–1980s brought higher precision and additional features. Today, most multimetri are compact, affordable, and essential tools for professionals and hobbyists.