The basic multimeter can be analog with a dial or digital with an LCD display. A multimeter is used to make electrical measurements of AC and DC voltage, AC and DC current, and resistance.

In electrical theory an ideal multimeter has no effect on the circuit being measured. An ideal voltmeter would have infinite resistance, so no current could flow through it while it is attached to a circuit. An ideal ammeter would present no resistance to a circuit. Real multimeters do not achieve this ideal, so their readings will very closely match theoretical, calculated values for a circuit, but never with absolute precision.

It is called a multimeter beacuse they measure voltage, current and resistance. Some can also test diodes. A multimeter is not to be confused with a megger which is somewhat riskier to use.

The typical multimeter has a range setting and many digital models have auto ranging. Many have a dial to switch between the various ranges and AC/DC.

Digital multimeters are generally battery operated allthough there are test bench designs that work off a power supply.

An advanced multimeter can also measure temperature, inductance, capacitance, Frequency and duty cycle.
Its a good idea when purchasing a multimeter to buy one with more than the basic features. A diode checker can be very useful for example. Another important factor is the accuracy of the device and the functional operating range. Does it have an auto range feature.

Some technicians feel that the older analog models have thier advantages over the digital multimeters but generally the digital meters are more popular.

If you would like to purchse a multimeter or learn more visit www.electronics-laboratory.com