Do you have a receptacle outlet in your home that has an open ground or neutral? Some older homes from the 1960’s and 1970’s were wired with no bonding wire. This is visually identified by there being no ground pin on a receptacle. However, it is very likely that a older home has gone through several electrical renovations and may have incorrectly wired receptacles from previous DIY attempts.
The most common problem is an open ground. This is because the bond wire is either not attached to the receptacle outlet terminal or missing entirely. Read on in this article to see how you can fix it and how to determine if you have a open circuit problem.
Cost to fix a open ground or open neutral
Depending on your situation you may need to replace a receptacle outlet device or make wiring changes. Expect a 1hr or 2hr service charge for minor labor and minimal material cost. A typical electrical outlet can cost $2 – 3 dollars where as a GFCI outlet can cost over $20 dollars. Every situation and electrical contractor bills out differently. Your final cost could be anywhere between $75 – $350 dollars depending on difficulty, time spent and materials needed.
Detecting a open ground or open neutral in a branch circuit
First off you will need to identify that you have an open ground. There are 2 ways to discover this problem.
The first way would be to turn off the power to the circuit and see if there is continuity between the neutral wire and bond wire (ground pin). In a correctly wired circuit there will be continuity. If there isn’t you will need to find out why there isn’t continuity.
All homes have the service neutral bonded to ground. You wont be able to see this connection because it usually happens in the road transformer mounted on the hydro pole, inside your meter-base, or via a bonding strap inside the main enclosure of your panel. Do not attempt to remove the main cover on your panel as turning off the main breaker will not shut off the power in the main side of the panel. The only way to turn off the power is to contact your hydro utility provider and get them to disconnect your electrical service from outside.
The second way which is far easier then the first is to use a receptacle testing tool. They are used to detect issues with GFCI’s, open neutrals and reversed wiring on receptacles. This type of tester is an economical, easy to use tool designed for testing a large amount receptacles quickly.
What if my receptacle doesn’t have a ground pin?
If your outlets use two slot receptacles without a round grounding pin slot, it’s a sign that the electrical wiring system itself may not be grounded and will need rewiring.
How do I fix the open ground?
We have identified the problem, now we need to fix it. Sometimes on older homes the bonding wiring that would normally attach to the outlet box and jumper to the receptacle ground terminal is missing. In this case you may want to open up the walls or attempt to fish in new wiring. This makes sense if your planning a renovation anyway.
Pro tip: don’t forget to change any old wiring while wires are readily accessible during a home renovation.
However if you are unable to renovate and run new wiring you can replace the outlet with a GFCI -ground fault circuit interrupter.
Installing a GFCI receptacle on a open ground outlet
Start by wiring the GFCI receptacle as the first device in the circuit. This will allow all the load side outlets of the GFCI to be protected via the first outlet being ground fault protected. The incoming wiring is referred to as the Line side of the power and connects to the line terminals on the GFCI. The Load terminals of the GFCI connect to the wires leaving the outlet box which connect to the remaining daisy chained receptacles in the room.
Testing the GFCI would trip power to all receptacles in the branch circuit when wired correctly. Restore power to a tripped GFCI by pressing the reset button on the GFCI.
Open neutrals can be tricky to find and isolate. This why many home owners cant fix the problem themselves. Don’t feel bad there are plenty of professional electricians that can’t figure it out either.
Since there are many reasons for this issue I will simply list out the most common problems that I come across while providing electrical service to customers at Green Electric & Automation.
Receptacle quick connects
By far the most common reason for a open neutral is a bad connection. Let that sink in for a minute. On most receptacles there are two ways to terminate the electrical wiring.
One way is to strip the wire insulation off your wire and curl a hook of bare copper wire to tighten around a the device set screw. The other way is to strip the wire insulation and jab the bare copper portion into the quick connect terminals in the back of the plug.
This is the most common failure point as the push-in connection is not very reliable.
Why do quick connects cause wiring issues?
This problem really comes down to installation error and not taking the time to do it properly. Sometimes the quick connect doesn’t grab the wire properly and the wire remains loose within the terminal.
If you did not strip the recommended amount of wire insulation off the wire, there will not be enough bare copper to grab in the quick connect terminal.
This is because the connection relies on a very small spring tensioned clamp that maintains the connection to the bare stripped wire. You can check for this issue with the power off and lightly pulling on the wires. This will confirm that the quick connect is actually gripping the wire adequately.
Although removing wires from the push-in quick connect is possible. Multiple cycles of removing and adding wires tends to wear out the clamp that grabs the wire. This can cause a loose enough connection to where it builds up heat in the device and fails.
You cannot fix the outlet as there are no serviceable parts. In my opinion a more reliable way to connect wires to a receptacle is by using the terminal screws on the sides.
Pro tip: If the wires pull out of the quick connect terminals with minimal effort, you need to replace the electrical outlet.
Did you cut the wrong tab on the outlet?
The second most common reason for a open neutral is that someone broke off the neural tab instead of the hot terminal tab on the outlet between the two screws on the side. Breaking off wrong side of the split tab on the outlet could lead to a rather serious and dangerous problem.
How is breaking off the wrong outlet tab a problem?
Firstly where would you find a split receptacle outlet? Generally they are located above the counter tops in a kitchen. They are split to accommodate more power usage typically used by kitchen appliances.
To create a split receptacle you need to break the tab joining the hot terminals. Failure to do this will give you a rather unpleasant surprise when you turn on the 2 pole breaker in your electrical panel for the the first time.
The reason this is soo dangerous is because you are essentially shorting (2 lines of 120v makes 240v) 240 volt power together.
If you made this mistake you should be questioning your abilities and seriously consider hiring a electrician. Miswiring this connection can cause a fire, a blown breaker or scorch marks surrounding the incorrectly wired outlet device.
How did these burn marks get on the back of the kitchen counter? How embarrassing.
Visually inspecting a receptacle outlet will not always alert you to a defect.
You may be able to see heat cracks in plastic or burn marks on the receptacle outlet. Don’t cheap out and try to fix it, just replace the electrical outlet! Lastly, throw out the old defective outlet in the trash.
Pro tip: Trash the receptacle. You don’t want to deal with this problem again in the future because you saved a deflective outlet it to be in your tool box for later use.
These are just some of the problems that you can have with wiring receptacle outlets. Having a outlet with a open ground or open neutral can pose a electrical hazard or damage electronic devices that you plug in. If you don’t feel comfortable with making these changes contact a electrician that can help you out.
If you require electrical troubleshooting contact Green Electric & Automation to see how our services can help you.