How a multimeter works

How a multimeter works. A multimeter is among the most important and widely used laboratory instruments. Basic engineering measurements based on Ohm’s Law are taken with multimeters. This contains voltage, current, resistance, and other metrics. Handheld and tabletop multimeters are available. Good multimeters have a better level of accuracy than handheld multimeters.

How a multimeter works

Choosing the best multimeter is a difficult process. The pricing ranges vary greatly depending on the brand and characteristics. When selecting a benchtop multimeter, be sure to look into all factors you must consider.

Application of multimeter

A multimeter is electrical and electronic circuit troubleshooting equipment used to evaluate voltages and certify optimum operating levels. Current, resistance, and voltage are all measured with standard multimeters. Capacitance and inductance can also be measured using more costly devices. An oscilloscope may also include multimeter capabilities.

The purposes of multimeter include

  • The ammeter feature of a multimeter is used to count the number of electrons traveling through a specific spot to calculate the current. Amperes are the units used in this measurement. You may use the multimeter to determine how many amperes an appliance is drawing to determine if it is taking too much current, which could cause a circuit breaker to trip.
  • The ohmmeter function employs ohms to measure electrical resistance or the resistance to an electric current. If an electrical circuit is short-circuited, it will have a resistance of 0 or near zero ohms. When a circuit is open, the resistance is infinite, and there is no current flow.
  • Your multimeter’s voltmeter function detects the electrical potential between two places in volts and is particularly handy for determining whether a battery is pretty much dead.

Working of digital multimeter

Analog to digital converters, or ADCs, come in various shapes and sizes. The sequential estimate register, or SAR, is the one that is most commonly used in digital multimeters, or DMMs.

Some SAR ADCs have just 12 bits of sensitivity, whereas those used in test equipment, such as DMMs, typically have 16 bits or more, depending on the application.

DMMs typically have resolution levels of 16 bits and sample rates of 100k sample rate. Typically bench or standardized test devices only require measurements to be taken at a maximum pace of a few per second, up to ten per second.

Working of analog multimeter

The analog multimeter was the first of its kind. However, it is no longer in use due to recent technological advancements with the invention of digital multimeters. Despite these developments, it remains critical, and we must not overlook it.

The d’Arsonval galvanometer concept is used in analog multimeters. It has a needle that indicates the scale’s computed values. A deflecting torque is created by current flowing through the coil, causing the coil to rotate at an angle and the pointer to travel across a graded scale.

The regulating torque is provided by a pair of hairsprings coupled to the rotating spindle. The galvanometer is a left-zero functional status in a multimeter, with the needle resting to the extreme left of the scale from zero.


The three basic electrical properties are primarily used to measure voltage, current, and resistance. You may also use it to check for electrical continuity between two locations in a circuit. You cannot measure electrical quantities such as frequency, charge, and so on with a multimeter.

The highest current capacity of most multimeters is 10 amperes. It is also impractical to turn off the power and interrupt the circuit to take a measurement. Small DC currents are typical for direct current measurements using a multimeter.

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