Knowing how to use a multimeter is helpful
when doing electrical repairs and DIY maintenance projects.
A multimeter is an electrical tool
used to measure electricity.
You may also hear it called a volt ohm meter or multitester.
You can use a multimeter to check the AC
voltage in an electrical outlet and test
DC voltage in batteries.
Let's start by turning it on.
There's some multimeters have an on/off button or switch.
But your model could have an auto off feature
to save battery life.
Your display will show the measurement.
Use your selector knob to select your unit of measurement.
And most multimeters have two ports.
But some devices can have up to four.
All multimeters have a common port.
It's the grounding or neutral port, and it's black.
The V Omega MA port is red and used
for testing most measurements.
The 10-A port is red but used less frequently.
It's for handling large currents or up to 10 amps.
The black probe always plugs into the common port.
It doesn't carry live electricity.
The red probe plugs into the port for the unit or property
you're measuring.
It tests voltage resistance or frequency.
It's the positive or hot wire.
To read the meter, it helps to understand the symbols.
V stands for voltage.
A stands for amperes or amps.
This is the symbol for ohms.
M is milliamps, which are tiny fractions of amp peers.
Each one is 1/1,000 of an amp.
A wavy line indicates an alternating current.
A straight line indicates direct current.
Before you begin, to check for cracks on the multimeter
and for any fraying or nicks on the wires.
Next check that your probes are working internally.
This is sometimes called ohming out the leads.
Plug the black probe into the common port.
Insert the red probe into the jack marked for ohms.
Set your multimeter to the ohm meter on the selector knob.
Then gently tap the red and black tips together.
Your reading should be 0.5 ohms or less.
If your reading is higher than, that replace the probes.
Measuring AC voltage is the most common usage of a multimeter.
Follow these steps to check an outlet.
If you're testing another electronic device,
the concept is the same.
Set the mode on your multimeter to AC voltage.
Connect the black probe to the common jack on the multimeter.
Plug the red probe into the jack labeled as AC voltage.
Place the end of the black probe into the neutral slot.
On a polarized plug, place the wider prong.
Put the red probe into the hot slot
on the plug, the smaller slot.
Check your reading.
It should read around 120 volts.
When you're done, remove the red probe then
the black from the item you're testing.
Unplug the probes from the multimeter in that same order.
You can also use the multimeter to check
DC voltage in a battery.
Disconnect the battery from any power tools or chargers.
Set your multimeter to measure DC voltage.
Use the selector knob or button to choose
the expected measurement.
For example, a AA battery should be around 1.65.
So I'm going to set mine around 1 or 2.
Touch the black probe to the negative side of the battery.
Touch the red probe to the positive terminal.
Check your reading.
Disconnect the red probe then the black one from the battery.
Then disconnect it in the same order on the multimeter.
Now that how to use the multimeter,
you can troubleshoot your next DIY project.
To get started, you'll just need a millimeter and the materials
you want to test.
Good luck and thanks for shopping at the Home Depot.