How to test a GFCI Breaker with a Multimeter

How to test a gfci breaker with a multimeter. If your Ground fault circuit interrupter is not working accurately or loses functionality, try out the basic test using a multimeter. It’s an Easy and efficient test to check the Ground fault circuit interrupter working.

Efficiently working gfci breaker ensures individual safety from electrocution. Try testing your gfci breaker in case of failing the test purchase, a new one for better functioning.

Let’s get started!

How to test a gfci breaker with a multimeter 

Many professionals and experts advise testing the gfci breaker once a month if it’s functioning well. It will ensure the safety associated with the gfci outlet. In case of faulty gfci, there is no indication shown unless you test it with a multimeter.

Safety Equipments and Tools

Whenever you are working with an electrical device, safety comes first.

To avoid any mishaps, try using these:

  • Electrical personal protective equipment before testing the Ground fault circuit interrupter.
  • electrical insulated rubber Gloves
  • The protective layer on the ground makes a barrier.

A multimeter helps you troubleshoot the gfci breaker. You can find the resistance, amperage, and voltage of electricity. Analog MultiMate is cheaper than a digital one because the DMM is advanced in its results-giving capabilities.


Follow the step-wise guidelines to test the gfci with a mutineer.

Checking Outlet Voltage

  1. Take the gfci device and cut the power by using the TEST button.
  2. The Gfci breaker consists of two buttons between the plug connections.
  • Test
  • Reset
  1. Gently pressing the test button gives off a clicking sound, ensuring the outlet power supply is off.
  2. To check any leftover current, insert the plugs of the digital multimeter to the vertical slots of gfci.
  3. Two slots are present in gfci, insert the black lead (negative) of the multimeter first, and then the red one (positive)
  4. A value zero on the device indicates no current.
  5. Now reset the device by gently pressing the RESET button.
  6. After pressing, the current starts flowing.
  7. Now proceed to check the voltage of outlets.
  8. Testing aims to determine whether the outlet is giving off exact voltage or not.
  9. For that, set the multimeter to maximum AC voltage, depicting a wavy shape line. While in the case of DC, it shows a straight line.
  10. If the gfci on which you are working is a single-pole breaker, you will observe 110 volts while 220 volts for double pole breaker.
  11. If no value appears on the device, there might be an issue with the wiring.

Checking the Outlets For Properly Grounded

  1. To check whether the outlet is grounded or not, use a multimeter to check the voltage value.
  2. Take a multimeter to insert red lead to the gfci slot while black one to u -shaped gfci slot meant for ground, present inside the device.
  3. It follows the same step for outlet voltage checking except for the black lead inserting site.
  4. The same voltage values indicate no problem in the outlet grounding.

A change in voltage indicates problems like reverse wiring.

Checking The Outlet’s wiring

  1. Turn the power off before inspecting the wires.
  2. After that, locate any misconnected or switched wires
  3. The b
  4. lack wire connects with the line pair that are black, while the white wire with the lead wires is white.
  5. Match the colors black – black and white – white. If no match occurs, there might be a problem with the wiring.  Call the professional to solve the issue.
  6. In the end, recheck the outlet’s voltage with a digital multimeter.


To test the Ground fault circuit interrupter, try out the test using a multimeter. It’s an efficient way to check the Ground fault circuit interrupter working. The gfci breaker ensures individual safety from electrocution.

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