What is a Bootleg Ground?
A bootleg ground, also called a false ground, is a situation that is created when a jumper wire is installed on an electrical receptacle between the ground screw and the neutral screw. (see photo) Installing this jumper is often done when a two-prong receptacle is replaced with a three-prong receptacle. When there are two-prong receptacles in the home, the home is often wired with a wiring system that only includes a hot and a neutral wire and not a ground wire. Without running a new set of wires that includes a ground wire from the breaker panel to the newly-installed receptacle, this receptacle cannot be grounded.
Why do People Create Bootleg Grounds?
Since running the new wire is expensive, the person installing the new three-prong receptacle, will sometime install a jumper wire between the ground screw and the neutral screw. In a sense, this “grounds” the outlet, and makes it appear grounded when a receptacle tester is plugged in. People often justify this bootleg ground by saying that since the ground and neutral wires are tied together at the electrical panel, it’s ok to tie them together at the receptacle. While it is true that they are connected at the electrical panel, they cannot be tied together at the receptacle. Bootleg grounds are specifically PROHIBITTED by the National Electrical Code because they create a dangerous situation.
Why is a Bootleg Ground Dangerous?
Before explaining why bootlegs are dangerous, I will start with a quick and simplified explanation of how an electrical circuit works. Electricity flows from the breaker panel to the receptacle through the hot (black) wire. From the receptacle it then flows through the cord to the device that is plugged in and then back through the cord to the receptacle. Finally, it flows back to the breaker panel through the neutral (white) wire. Summed up, only the hot and neutral wires are designed to carry current. On a properly grounded receptacle, the bare ground wire is not designed to carry current under normal circumstances. It should only carry current in a fault situation, and it carries this current in order to trip the breaker and deenergize the circuit to protect everyone in the home from possible electrocution.
Bootleg grounds are dangerous for several reasons. First, let’s suppose that you have a receptacle with a bootleg ground. If there is a problem on the receptacle containing the bootleg ground where the neutral wire becomes damaged or disconnected somewhere, then anything that is plugged into the receptacle will become energized and will put anyone in your home at risk of being electrocuted by simply touching the device that is plugged in.
Secondly, GFCI-protected outlets downstream from a receptacle with a bootleg-ground may not trip in the event of a ground-fault situation. Since GFCI’s are designed to protect the home’s occupants from possible electrocution, a non-tripping GFCI receptacle puts you more at risk of electrocution. Read more about GFCI receptacles here.
Put another way, proper grounding is designed to make a home’s electrical system safer, and to protect its occupants. A bootleg ground does just the opposite – it makes the home’s electrical system more dangerous, and it puts the occupants more at risk.
How to Know if your Home has any Bootleg Grounds?
A simple electrical receptacle tester will not tell you if you have any bootleg grounds. It will require an inspection by a licensed electrician or a home inspector who uses a more specialized device, such as a Sure Test Circuit Analyzer, to test receptacles.
What should you do if your home has Bootleg Grounds?
The short answer is that you should have them corrected by a licensed electrician. If your home uses an older wiring system that does not include a ground wire, then the receptacles in your home will not be grounded without rewiring your home. Having said this, you do not have to rewire your home to gain some protection. There are several things that you can do. You can leave two-pronged receptacles installed on all of the circuits without a ground wire. This will prevent giving the false sense of security that ungrounded, three-prong receptacles can give. (You can read more about the differences between grounded and ungrounded receptacles here.) Another thing that you can do is to have GFCI-protected receptacles or breakers installed on all of the ungrounded circuits in your home. This will greatly increase the safety of the electrical system in your home.
© 2019 Mike Morgan
This article was written by Mike Morgan, the owner of Morgan Inspection Services. Morgan Inspection Services has been providing home, septic and well inspection services throughout the central Texas area since 2002. He can be reached at 325-998-4663 or at firstname.lastname@example.org. No article, or portion thereof, may be reproduced or copied without prior written consent of Mike Morgan.