A Closer Look at Ground Fault Interrupters

After collecting tons of tools over the years, you've decided to do the responsible thing and build a few shelves in the garage. Feeling ambitious, you grab your trusty electric drill, and plug it into the outlet.  But as electric current flows to the cord lying on the ground, the power drill suddenly turns off. Frustrated, you assume the issue is with your tool or e outlet, so you check your tool and the outlet to see if everything is working. What you may not realize is the reason your power drill shut off is because of the ground fault circuit interrupter, or GFCI. Let’s take a closer look at what ground-fault is, and how GFCIs are used to keep us safe from electric current.

So, What is Ground Fault? 

When electric current flows unexpectedly to another source of ground it is considered a fault. Ground fault occurs when an electric current finds an alternative path or route to reach the ground. When part of your body, tool, ladder or some other object comes in contact with an energized circuit such as a bare wire, you can become the alternate path for the current to rapidly reach ground. Ground fault can actually cause severe electrical shock to the body, and in many cases death. Note: one thousand milliamps will kill a human.

Electrocution can occur when an appliance with metal parts is exposed to electrical current. There are a number of ways current can reach the frame of an appliance including, moisture, deteriorating cords, motors and other electrical parts that are worn and broken. Gnawing from tiny little critters and rodents can also create wire shorting and uncover electric current.

What are ground fault interrupters used for?

Although a ground fault is troubling, the good news is you can mitigate damage caused by a fault. Typically a 120-volt outlet in the US is comprised of two vertical slits, with the left side being larger and a small round circle situated betwixt the slits. The right slit is called “hot,” the left, “neutral” and the circle, “ground.”  Once an appliance is plugged into the outlet, electricity should stream from hot to neutral.  A GFCI watches or monitors the current that flows from hot to neutral. When an interrupter detects a difference between the current on each side, it trips (disconnects) the circuit, basically saying, ‘there seems to be something wrong here.’ Once issues are detected the outlets react quickly, shutting down electrical charge in less than a second. Basically the GFCI is a watchdog of sorts, making sure that the current coming in and going out is the same. Because of rapid action (millisecond), you will not be electrocuted or killed, but possibly shocked.

GFCI Types 

GFCIs are usually available in three different categories: circuit breaker, portable and receptacle. Each one works differently.  Installed in a panel box to protect circuits, circuit breaker GFCIs shut off when ground faults occur and when circuits are shorted or overloaded.  Protective breakers are typically used to cover high-power appliances such as heaters, lighting fixtures, and the wiring in your outlets.

Receptacle GFCIs take the place of the standard receptacles within homes. Sitting inside regular outlet boxes, receptacle GFCIs protect you against faulting from a portable electrical device. GFCIs may be installed on older non-grounding two wire conductors.

Finally, portable GFCIs can be used in place of permanent GFCI outlets. These can come in the form of extension cords or as a simple box that plugs directly into an electrical outlet.  Many power strips and battery backup units incorporate GFCIs into their native designs.

Installation and Testing

Installing and testing GFCIs is vital. Both receptacle and circuit breaker GFCIs should be installed by a licensed electrician. However, portable GFCIs do not require an electrician or any essential tools.

To ensure safety and functionality, it is advised that you test your GFCI receptacle at least once a month.  To test your GFCI receptor, simply plug your lamps into the receptacle and hit TEST. Once this is done, the GFCI RESET button will pop out, and the light should disappear.  During testing if you notice that the light is not going out while the RESET button is popped out, it usually means the receptacle was not installed correctly. Furthermore, if the button does not come out and the light does not come on, your receptacle is defective and you should consult an electrician.

Hopefully this helps you better understand the dangers of ground fault. Remember, this is an issue that can be avoided with the proper use of GFCI receptacles. What have your experiences been with ground fault? Feel free to write your comments or questions below, and as always, drop us a line on Facebook, Twitter, Linked In, Pinterest, or Instagram.