How to Test an AC Current Polarity Matter

If you think the power source for your AC device is failing, you should test it before discarding the whole unit. This can be done with a voltmeter. A voltmeter is a small device that tests the power output of various electronic devices. You don't need to be an electrician in order to use these units, and testing your AC device won't take longer than a moment or two.

Voltmeter

Instructions

- 1
  Plug the included red lead into the "+" terminal on the front of your voltmeter.
- 2
  Plug the included black lead into the "-" terminal on the front of your voltmeter. Placing these leads in the correct slots ensures the appropriate polarity of the voltmeter, allowing you to clearly read it.
- 3
  Turn your voltmeter on and set the switch on the front of the unit to "AC V." This ensures the devices measures power in "AC" voltage.
- 4
  Place the negative lead onto a nonelectric area to ground it. Place the lead on the negative terminal if you are testing an AC device that has a negative terminal.
- 5
  Turn on the device you intend to test and place the red lead on the power source or its positive electrical terminal. The meter will then produce a reading in "AC" volts.

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