Electrical

What Is An Open Ground: Troubleshooting & Fixing An Open Ground

open ground lg

An open ground outlet occurs when a three-prong electrical outlet is not connected to a grounding conductor, which is essential for safely directing excess electrical current away from users and connected equipment.

This situation can arise in older homes with outdated two-wire electrical systems that lack a ground wire or where a ground wire has been disconnected or was never connected properly.

The open ground outlet meaning the electrical cable, lacks a ground wire and presents a risk of electric shock, electrocution, and damage to electrical appliances due to the lack of a safe path for excess electricity to dissipate.

Troubleshooting Open Grounds

You can use an outlet tester to indicate the condition through a specific light pattern to identify an open ground outlet. Alternatively, physically inspecting the outlet by removing it from the wall and checking if the ground wire is connected correctly can also reveal an open ground.

Fixing an Open Ground

The approach to fixing an open ground depends on the specific circumstances of the electrical system:

  1. Reconnect the Ground Wire: If a ground wire is present but disconnected, simply reconnecting it to the outlet can resolve the issue. This straightforward fix requires knowledge of electrical systems and safety precautions.
  2. Install a GFCI Outlet: For outlets that cannot be grounded due to the absence of a ground wire, installing a Ground Fault Circuit Interrupter (GFCI) outlet is a recommended solution. GFCI outlets can prevent electric shock by quickly cutting off power during a fault. Labeling these outlets as having “No Equipment Ground” is important to inform users of their status.
  3. Replace with a Two-Prong Outlet: If grounding is not necessary for the devices being plugged in, such as lamps with two-prong cords, replacing a three-prong outlet with a two-prong outlet is an option. However, this limits the types of devices that can be safely used.
  4. Run a New Ground Wire: The most comprehensive solution involves running a new ground wire from the outlet back to the main electrical panel. This option ensures proper ground but can be labor-intensive and costly, especially if it requires opening walls. It is typically considered during renovations or when installing new electrical circuits.
  5. Insurance and Building Codes: It’s worth noting that some insurance policies and local building codes may require that open grounds be corrected, especially during home sales, renovations, or when changing insurance providers. Compliance with the National Electrical Code (NEC) and local regulations ensures safety and avoids potential legal or financial issues.
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What Does Open Ground Mean?

Open ground meaning has little to do with the three-prong receptacle outlet. The outlet doesn’t provide grounding; the wiring does.

I know it’s vague, but you’ll understand open grounds better as we move along.

The National Electrical Code dictates that every electrical outlet and fixture in residential buildings must be grounded. Grounding enables faulty current, which would otherwise be dangerous above ground, to safely find a path to discharge unwanted current to the ground.

A receptacle is an electrical socket or a wall plug outlet usually installed on walls. The purpose of a case is to discharge electric power from a circuit for home consumption by powering electrical devices and household appliances. 

There are two most common and popular types of receptacles/sockets:

  1. Two-prong receptacle (outdated)
  2. Three-prong receptacle

Two-prong Receptacle (outdated)

The two-prong receptacle is outdated and goes way back to the 1960s, but it is still widespread as it is still present in older homes’ wiring systems.

Many homeowners don’t want to go through the hassle of replacing it as long as it’s working. On the other hand, some people are trying to upgrade by replacing them with a three-prong receptacle.

The two-prong receptacles are considered unsafe because of their lack of grounding. Unlike the two-prong, the three-prong connects to a home’s grounding system.

Three-prong Receptacle

A three-pronged receptor has two aligned but uneven slots on the top space and one “U” shaped place on the bottom area. The larger slot on the left is “neutral,” the smaller slot on the right is “hot,” and the “U” shaped place on the bottom is “ground.”

An open ground outlet is any faulty current or circuit that does not route to the ground. Meaning that safety from electric shocks and damage is not present or guaranteed.

Is Open Ground Dangerous?

An open ground is dangerous. Anything that has or conducts electricity is dangerous and must be handled with enough caution. 

An open ground as an electrical product is unsafe. 

Most open ground problems go unnoticed until they shock someone or cause a sudden fire.

That is why it is crucial to do a frequent home inspection on your property. 

What is a Grounding Wiring System?

A grounding system is a part of a home’s electrical wiring system. It installs electrical cables and devices such as switches, distribution boards, sockets, and light fittings in a building/home. 

The primary and most important purpose of earthing or grounding is to reduce the dangers of electrocution and fires that could potentially destroy homes. An electrical system that is adequately grounded ensures the safety of lives, electrical wires, and electrical devices.

During wiring, three types of wires are used;

  1. Live Wire (Red or Black Color)
  2. Neutral Wire (White Color)
  3. Ground/Earth Wire (Green Color or Bare Copper)

A live/hot wire is an active wire that carries electrical current in voltage. Live wires are red to alert people of the danger they pose.

Neutral and earth wires alternate/circulate current in an electrical system. While the neutral wire brings the circuit to a ground/bus bar connected to the electrical panel, the earth wire provides an electrical connection to the ground. The purpose is to provide a path for faulty current to flow to the ground.

What is a Grounding Rod?

A grounding rod is a thick wire that has meager resistance. It acts as a line of defense against the various safety risks a faulty may pose and is, therefore, a crucial wiring part of having a complete and safe electrical system. 

There are various types of rods installed according to different environmental conditions. 

Types of Grounding Rods

  1. Stainless steel grounding rods
  2. Solid copper grounding rods
  3. Copper-bonded grounding rods
  4. Galvanized grounding rods

Copper-bonded grounding and galvanized grounding rods are the most common types worldwide.

However, the stainless steel and solid copper grounding rods are set aside to meet the needs of regions with unique weather conditions.

In a grounding system, the grounding rod installation is involved. 

A grounding rod called a grounding electrode is usually installed in the ground close to the main electrical servicing board. 

Its primary purpose is to provide fault current with a low resistance path to deposit unwanted, excess, and unsafe drafts to the ground.

Grounding rods are either 8 feet or 10 feet long, but the 8-foot is commonly used in residential wiring installations.

When installing the grounding rod, one must find a suitable location near the house and the service panel. 

For proper installation, at least ¾ of the rod length is driven deep into the moist ground. A flexible grounding wire that goes directly to the distribution panel system inside the house is attached to the protruding end.

What is Fault Current?

A fault current is unintended when one electrical conductor or more transmits to itself, each other, or the ground.

It is not uncommon to experience a fault current in an electrical circuit—the presence of an open ground results in accidental electric shocks and device damage.

Electric current is the normal systematic flow of electric charges between two points through an electric wire. 

This current is measured in amps, with electric charges between points A and B. 

A service panel receives incoming electric power from the utility company through the primary meter in any regular electrical circuit. It distributes each course that supplies the various household lights, outlets, appliances, and other devices throughout the house.

The circuit then flows back to the panel where circuit breakers are installed. These circuit breakers trip to interrupt any faulty current flowing in by cutting off the power supply to the circuit.

Other electric fault devices include:

  • Fuses
  • Relays

Fuses

A Fuse is a small but effective electrical safety device containing a strip of wire that heats up and melts to break the electric circuit when it encounters a faulty current. 

It protects both the wiring and the appliance because a current in a faulty condition carries more current than an average electric current should. 

Fuses are not used widely now that circuit breakers have replaced them.

Relays 

On the other hand, an electrical relay is a control switch with input and contact terminals used to stabilize electric current in electrical circuits. 

Its purpose is to connect with one circuit as it breaks contact with another.

Types of Electric Fault Currents

When you talk about electrical faults, many tend to think that it is just one type and are surprised when they learn that there are several different types of defects:

  • Phase to ground
  • Double phase to ground
  • Three-phase to ground
  • Phase to phase
  • Three phases

What Danger Can Fault Electrical Current Pose?

In a typical electric setup, electric current flows through a cable, and different wires have an additional carrying capacity.

Standard cable sizes include 14-, 12-, 10-, 8-, 6-, and 2-gauge wire. The wire size dictates how much current can safely pass through it at a given time. A Wire gauge directly relates to how many amps you need to run through it.

And because faulty current results in a condition where the voltage (amps) flowing through the cable surpasses its carrying capacity, several damages might happen:

  1. Cable damage.
  2. Electrical circuit damage.
  3. Electric shock.

Finding and Testing For an Open Ground in a House Circuit

An electrician’s best tool or instrument is an outlet testing tool for finding and testing for open ground.

An ordinary electrical circuit system anticipates an excess flow of current charge. This excess and unwanted current is known as fault current.

Fault currents can damage electrical cables in the electric circuit, causing damage to household appliances connected to the outlets. It may also hurt people if left unmanaged. 

The grounding system, by default, provides this faulty current with a path to safely deposit to the ground instead of causing a safety hazard. The National Electrical Code stresses the need to ground all electrical outlets.

The service distribution panel is the central unit for all electrical connections within a home. From this point on the wall, the distribution panel feeds from the outside main meter, dissipates excess voltage to the grounding system, and supplies different home parts through other electrical circuits.

  • A certified electrician must handle this task of troubleshooting and fixing an open ground for safety reasons.
  • Grounding is mainly connected to outlets, and these outlets happen to be receptors/sockets. To find out the source of open ground, the electrician must first locate every outlet within the home.
  • When he does locate an outlet, he will insert an outlet tester into a receptacle to determine if the outlet box contains a grounding wire that is not doing its job of routing insufficient current to the ground. 
  • An outlet tester has three light indicators. The indicator in the middle comes on if a grounding wire in question is not routing inadequate or faulty current to the ground.
  • One by one, the electrician will keep testing every other outlet until he finds the one with the problem.

How to Fix an Open Ground?

An open ground is when no grounded conductor is installed in the electrical system. This missing ground can create a safety hazard if a short circuit occurs. There are several methods you can use to fix an open ground properly:

Install a Two-Prong Receptacle

The simplest option is to remove the 3-prong outlet and replace it with a 2-prong outlet, as only hot and neutral wires are present. However, this also eliminates the third prong for any appliances that need grounding. Be sure any nearby outlets have successfully tested as grounded before using this solution.

Install a GFCI Receptacle

One of the easiest ways to fix an open ground is by replacing standard receptacles with GFCI (ground fault circuit interrupter) outlets. The GFCI will shut off power if it detects an imbalance of current flowing through the hot and neutral wires, providing protection similar to a ground wire. Just make sure to label the GFCI outlet with a “no equipment ground” sticker so future electricians know there’s no true ground.

Rewire the Circuit

Rewiring the home run from the breaker panel with a grounded cable that contains a ground wire is the best permanent solution. While more labor-intensive than other options, completely rewiring ensures all receptacles on the circuit are properly grounded.

Fish New Ground Wires

In some cases, you may be able to fish a new ground wire through walls to add a ground path back to the panel. There are specific code requirements for suitable grounding conductors and connections when using this method, as spelled out in NEC 250.130(C). Consult a qualified electrician on properly implementing this solution.

Install GFCI Breaker

Like a GFCI outlet, you can protect an entire branch circuit by installing a GFCI circuit breaker in the main panel. This option provides easier ground fault protection for all outlets downstream with just one device. Again, all receptacles need a “no equipment ground” label when using this method.

Open Ground But Ground Is Connected

If you have a receptacle showing an open ground but there’s a ground wire present, then you have loose or poor ground somewhere in the circuit path. This can occur if the ground wire has a loose connection or corrosion that increases resistance.

The loose ground can occur at:

  • any receptacle on the circuit, so you’ll need to check them all.
  • at any wire connection, inside or outside a junction box.
  • inside the electric panelboard.

Check connections on the receptacle or switch and the splice joining the incoming ground wire in the box. Look for loose screws or terminal block connections that may need tightening with pliers. Examine wires for signs of corrosion or damage that could prevent good metal-to-metal contact.

Also, verify ground continuity by performing resistance testing using a multimeter. Compare resistance readings between the equipment ground terminal and neutral terminal. Properly grounded circuits should show very low resistance, usually under an ohm. Higher resistance points to a problem joint in the ground path.

A qualified electrician must troubleshoot and trace the electric current flow to repair open grounds with grounded wiring.

When Do You Need an Electrical Safety Inspection?

There are certain times when you need an electrical safety home inspection. The Electrical Safety Foundation suggests electrical inspections during these times:

  1. During the purchase of a new home
  2. If a home is over 40 years old
  3. After the completion of a major renovation
  4. When adding appliance

Grounding electrical wires is a must. It is according to the National Electrical Code. Grounding the cables will ensure the safety of lives and property.

Most homeowners inspect their property when they want to sell it. But most are oblivious to open ground problems and only become aware of them during a home inspection

The home inspection is conducted by either a building inspector or a certified electrical contractor.

They thoroughly inspect all your electrical systems, ensuring all electrical wires and components meet standards. 

An inspector’s job is to check if:

  • The service unit is carrying enough current to supply the entire household sufficiently.
  • The wiring system is in good working order.
  • The wiring has a grounding system.

Often, after an examination, the electrical inspector will provide a detailed checklist of where it needs immediate attention or even where it needs an upgrade.

Author

Hubert Miles | Licensed Home Inspector, CMI, CPI

Hubert Miles is a licensed home inspector (RBI# 2556) with more than two decades of experience in inspection and construction. Since 2008, he has been serving South Carolina through his company, Patriot Home Inspections LLC. As a Certified Master Inspector, Hubert is dedicated to providing his expertise in home inspections, repairs, maintenance, and DIY projects.