GFCI Keeps Tripping

If your GFCI trips continuously, you’re not alone.

A GFCI protection is designed to trip when it senses an electrical ground fault. This could signify a problem with the wiring in your home or that you’re connecting too many appliances to a single GFCI unit.

We want to help you protect yourself and your loved ones from potential electrical hazards. With our help, you can rest easy knowing that your home is properly equipped with functioning GFCI outlets.

Read the article till the end for more information on how to troubleshoot and fix a tripping GFCI!

What is the Purpose of GFCI?

We introduced you to all the important concepts about the ground fault circuit interrupter, GFCI, in our article “How Does A GFCI Work?” This included the need for GFCI, its functioning, the difference between a regular circuit breaker (CB), GFCI circuit breaker, and AFCI, where it should be used according to the National Electric Code NEC, types of GFCI, and testing procedures for GFCI.

We had even briefly introduced you to the reasons behind its nuisance tripping. In this article, we will further detail these concepts to make them further clear for you. But first, let us recall a few important concepts to understand the subject better.

  • GFCI is an electrical protection device that senses and clears any ground faults that may cause the related electrical current to flow through a human body, resulting in electrical shock or electrocution.
  • They work by comparing the current flow between the hot wires and the neutral. The difference indicates an electrical leak through an unintended path, resulting in neutral wires carrying a lower current. This difference translates into a magnetic field that activates the mechanism related to GFCI tripping.
  • In America, the sensitivity of such devices, which is the minimum current required by the GFCI to trip, is 5 mA. In Europe and other countries, the value of minimum current leakage is 10 mA.
  • They are specifically required in all wet or moist areas, bathrooms, outdoors, garages and accessories, basements, crawl spaces, laundry rooms, kitchen countertop surfaces, sinks, bathtub or shower stalls, boathouse, locker rooms, etc. They must be used with cord-connected appliances and outdoor equipment.

How do I know if my GFCI is bad?

To rule out a faulty GFCI outlet, you should test your GFCI just after installation to rule out any inherent problems in the wiring and once in a month thereafter. The tests are easy and can be carried out using the test button and the reset button on the outlet. You can use a separate tester for the purpose if you want. The methodology is described in our article “How Does A GFCI Work?

Nuisance Tripping of GFCI Electrical Outlet or Circuit Breaker.

Frequent instances of GFCI trips get labeled as nuisance trips, whereas the device is carrying out its intended function most of the time. As per my experience, for your own safety, it is very essential to troubleshoot and isolate/rectify the fault instead of forming any wrong notion and bypassing the device, which may be a code violation anyway. If required, hire the services of a licensed electrician to help you locate the real reason for these GFCI trips.

The common causes for these trippings include the presence of moisture, worn-out insulation, corroded wires, defective appliances, improper wiring, conductive dust, lengthier circuits, many appliances plugged into the same circuit, use of multiple location GFCI, and use of an incorrect type of GFCI outlet.

Common Reasons Why GFCI Outlet Keeps Tripping

In this section, we will explain to you in detail the common reasons why any GFCI breaker or outlets trip and how to trace such faults for your better understanding of the subject.

Improper Wiring

The faults related to improper wiring show up during the early stage of installation or if major rework or rewiring has been done. This usually involves reversed polarity (Interchange between the hot and the ground wire), GFCI outlets incorrectly installed, neutral feeding more than one circuit instead of a dedicated circuit, and loose connections of hot wire resulting in a ground fault.

It is better to take the services of a professional electrician during the Testing & Commissioning stage to certify your installation independently.

GFCI outlet feeds Power to Wet Areas

GFCI installed or feeding power to areas such as a bathroom, showers, kitchen, dishwashing, mop sink, locker rooms, garages, crawl spaces, laundry, rooftops, and outdoor areas are more prone to trippings. In addition, look for areas with excessive condensation. The presence of moisture reduces the insulation resistance and causes a small leakage current to flow. Your GFCI detects this leakage and acts to isolate the circuit.

Inspect the receptacle box for the presence of moisture after turning off the circuit breaker in the electrical panel. Use a blow dryer to completely dry out the receptacle box before attempting to switch back the GFCI power outlet.

Check if it is possible to reduce the moisture in the vicinity of the receptacle and the appliance plugged into it. Otherwise, install weatherproof boxes in these areas and definitely for all the bathroom and the exterior outlets to reduce the risk of electric shock.

If your GFCI continuously trips after rain, it is a clear indication of leakage currents due to the presence of moisture in the external areas and roof.

Use of multiple location GFCI to protect Multiple Electrical Outlets or many appliances

All circuits and electrical devices have a finite insulation resistance. Even if it is in the order of kilo-ohms or mega-ohms, some leakage current will flow. If you power several pieces of equipment from the same GFCI outlet, their cumulative leakage currents will exceed the threshold of the GFCI trip setting.

In addition, an actual ground fault in any one of the defective appliances may render all the other outlets on the same circuit powerless.

In such a configuration, it is a very tedious and cumbersome process to troubleshoot if a single defective appliance results in a tripped GFCI or is a cumulative effect.

The protected circuit is lengthy.

The other common reason for nuisance trippings in your ground fault circuit interrupter is the use of a very long cable or power cord. All such conductors have a capacitive reactance that causes a leakage current to flow to the ground. This leakage current varies with the type and size of the cable and has a direct relationship with the length of the cable feeder.

A large length will cause more leakage current to flow. If this value exceeds the setting of GFCI, the outlet will trip.

The deterioration of installed components over time

If your electrical installation has been in service for a reasonable period of time, like 12 to 15 years, chances are that many of the components have deteriorated over time, resulting in worn insulation, corrosion, presence of conductive dust, etc. These factors increase the level of leakage currents. In such situations, even a small trigger like a bit of moisture can cause the outlet to trip, which was not the case earlier.

Some appliances may have a higher leakage current.

Most of the appliances you use have prescribed limits of leakage currents in their UL listings. But, some of your actual appliances might have a manufacturing defect or gone defective during usage resulting in a higher leakage current. You may need to disconnect all the appliances on the faulty circuit and reconnect them one by one. If any particular appliance causes the tripping while the other appliances have connected back normally, you have identified the culprit.

Good Practices to Minimize Nuisance Tripping

  1. Keep the devices protected by each GFCI to a minimum.
  2. Each feeder length must be restricted to less than 150 ft.
  3. Install GFCI as per the manufacturer’s requirements and follow the relevant national codes.
  4. Get the installation certified by a qualified electrician.
  5. Test your GFCI at the recommended intervals.
  6. Use weatherproof units for external, rood, and areas with excessive moisture conditions.

Conclusion

This article has answered some of the people’s most common questions about GFCI outlets. If you are still experiencing problems with your GFCI outlet, it may be time to call in a professional. Let me know in the comments section below if you have any additional questions, and I will do my best to answer them.

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