How to Read an Analog Multimeter

By Isaiah David
Analog multimeters can be confusing for beginners.

Analog multimeters are simple and inexpensive, and they are accurate enough for most purposes. Although the best digital multimeters offer greater accuracy and other features that analog meters lack, such as overload protection, for most applications an analog meter will get the job done at a reasonable price. The biggest drawback to analog multimeters is that they can be difficult for beginners to read. There are several different scales printed on the same surface, and deciding which one to look at can be confusing at first.

Decide on the unit that you want to test. Analog multimeters usually measure voltage, amperage and resistance. Resistance is a measure of how much a wire or electronic component resists the flow of electricity; voltage is a measure of circuit "pressure"; and amperage is a measure of the amount of electricity flowing to the circuit. Many multimeters measure both AC and DC electricity, although some measure just DC.

Set the multimeter to the correct setting for what you want to measure. Your multimeter should be set to a higher value than you are going to measure. For example, if you want to measure the voltage in a wall socket and your multimeter has both 50v and 250v AC settings, set it to 250v AC. Otherwise, you will not be able to measure the full voltage, and you may damage your multimeter. Or if you are measuring a 100 ohm resistor and your multimeter has 10 ohm, 100 ohm and 1000 ohm settings, set it to 1000 ohms. That way, if the resistance is slightly too high, you will be able to detect it.

Disconnect the component from any power source if you are measuring resistance. For example, if you are measuring the resistance of a light switch, turn off the circuit breaker first. If you are measuring voltage or amperage, skip this step.

Place the test leads on either side of the unit you are testing. If you are measuring AC power, for example, put one lead in either terminal.

Look for the scale that corresponds to the setting you have. If you are measuring AC voltage and have it set to 250 volts AC, for example, there should be a scale that goes from 0V on one side of the multimeter to 250V on the other side.

Watch how far the needle swings. That is your value. For example, if your AC voltage needle swings 2/5 of the way between the 100V mark and the 150V mark, your AC is at 120 volts, which is normal in most areas of the United States.

Warning

Only use one hand when working with dangerous voltages. That way, if you get a shock it will not travel through your heart. Also, you will have one hand free to push yourself away should the voltage make your hand contract and hold onto whatever is shocking you.

About the Author

Isaiah David is a freelance writer and musician living in Portland, Ore. He has over five years experience as a professional writer and has been published on various online outlets. He holds a degree in creative writing from the University of Michigan.