When working with electricity and circuitry, one tool is the multimeter. This is perhaps one of the most commonly used and essential tools in the kit of any electrician. Today, we want to determine what a multimeter is and what it does.
A multimeter is an electricity-measuring instrument that measures various electrical properties. However, there are also some things that your standard multimeter cannot measure. So, what can a typical multimeter not do?
What is a Multimeter?
A digital multimeter is a tool used by technicians and electricians in the electronic and electrical industries. It is a standard diagnostic tool that can measure various electrical values.
These are accurate tools that long ago replaced basic needle-based analog meters. They are much more reliable and also have increased impedance.
Generally speaking, a multimeter will measure three things related to electricity: voltage, current, and resistance.
What do Multimeters Measure?
A multimeter measures voltage or volts, currents or amps, and resistance or ohms. So let’s look at all three of these things.
Technically, voltage is the pressure from an electrical circuit power source that pushes charged electrons or current through a conducting loop. This allows a current to do things such as power a lightbulb. Simply put, voltage equals pressure, and this is measured in volts.
The second thing a multimeter measures is current, measured in amps or amperes. Electric current is defined as the movement of electrons through a wire. It’s measured in amps − the number of charges that move through a wire per second.
Finally, a multimeter measures resistance, which is the force that counteracts the flow of a current. This tells you how difficult it is for the current to flow. Resistance is measured in ohms.
Some Multimeters May Also Measure
There are also some other readings that multimeters may be able to take. Let’s take a quick look.
Some multimeters may be able to measure what is known as capacitance, the ability of a circuit to collect and store energy in the form of an electrical charge.
Some multimeters may also be able to read conductance. This is the inverse of the resistance measured.
Some higher-quality multimeters may also measure decibels in circuitry, which is a logarithmic expression of the ratio between two signal powers, such as voltage or current levels.
Some multimeters can measure the duty cycle or duty factor; this is the ratio of time a circuit is on compared to how much it is off.
A Standard Multimeter Does Not Measure What?
So, we have covered the three things that your standard multimeter measures. However, there are also things that a typical multimeter cannot measure. So, let’s take a look.
Generally speaking, a multimeter cannot measure various electrical quantities. This includes things like charge and frequency.
Frequency is the measure of the oscillation rate, and it is measured in the number of changes per second. This is also known as Hertz. For instance, a generator with around 3,000 RPM will generate electricity at 50,000 Hertz. This is something that a multimeter cannot measure.
Moreover, a multimeter cannot measure charge, a fundamental property of matter carried by some particles. This governs how particles are affected by a magnetic or electric field. For example, an electric charge can be positive or negative and cannot be destroyed or created.
You should now know what a standard multimeter can do and what it cannot do.