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How to Use a Volt Meter to Check the Neutral & Ground

By David Sandoval
Voltmeters measure the voltage differential between the two probe leads.
multimeter image by Aleksey Bakaleev from Fotolia.com

Wall outlets serve as an interface for consumers to use electricity supplied by the power company. If you replace a power outlet, you will need to check the replacement to ensure that it is properly wired. One way of checking the outlet is by using a voltmeter or digital multimeter. Each socket blade in the outlet represents an electrical connection, making it simple to determine whether the outlet is properly wired.

The bottom round socket is
Light Switch and Outlet image by Towards Ithaca from Fotolia.com

Turn the voltmeter scale to “Volts AC.” Place the negative (black) probe into the bottom round socket (also known as “ground”) blade. Place the positive (red) probe into the left-hand (neutral) socket blade.

Check the measurement; it should indicate a voltage differential of zero.

Remove the positive probe from the left-hand socket blade, and place the probe into the right-hand (hot) socket blade.

Check the measurement; it should indicate a voltage between 110 and 125 volts AC.

Remove the positive probe from the right-hand socket blade. Remove the negative probe from the round socket blade.



  • Do not touch exposed metal while testing the connections. Test only in dry conditions.

About the Author


David Sandoval has served as a trainer and technical writer since 2000. He has written several articles online in the fields of home improvement, finance, electronics and science. Sandoval has an Associate of Applied Science in microelectronics from Northern New Mexico College.