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Kevin
Kevin, Licensed Electrician
Category: Electrical
Satisfied Customers: 2938
Experience:  29 years as a Licensed Electrical Contractor in Illinois, 5 year college Electrical Instructor, Former Electrical Inspector, Diploma in Digital Electronics, Former Illinois Licensed Home Inspector
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I have three outlets inoperative. When I use an extech et-10

Customer Question

I have three outlets inoperative. When I use an extech et-10 tester, it says "open neutral." What exactly is the problem?
Submitted: 1 year ago.
Category: Electrical
Expert:  Kevin replied 1 year ago.

Hello and welcome to Just Answer. My name is ***** ***** I will be happy to assist you with your electrical question.

1) The tester that you are using is a 3 prong cube tester that will also test a GFCI receptacle.

2) Any chance that you have a 2 wire lead AC voltage tester (a contact type) or better yet, an AC voltmeter available?

3) An "open neutral" means that the white neutral conductor has an open which is typically caused by a loose wire termination or a faulty wire splice. The neutral wire is the return wire on any 120 volt circuit. If an open neutral, then there is no return or path and therefore the receptacles are dead.

Customer: replied 1 year ago.
With a two wire voltage tester, there is no voltage indicated.
Customer: replied 1 year ago.
A voltmeter reads 72 volts AC.
Expert:  Kevin replied 1 year ago.

Thanks for the replies.

1) Let's try this using your voltmeter: At any of the dead receptacles, measure the following:

A) From Hot (short receptacle slot) to Neutral (long receptacle slot).........should = approx 120 volts

B) From Hot (short receptacle slot) to Ground (round hole)............should = approx 120 volts

C) From Neutral (long receptacle slot) to Ground (round hole)..........should = 0 volts or very close to it.

Let me know the 3 voltage measurements.........Thanks...........Kevin!

Customer: replied 1 year ago.
hot to neutral is 72.9, hot to ground is 121.6, neutral to ground is 41.73
Expert:  Kevin replied 1 year ago.

OK, thanks for taking the voltage measurements.

1) N to G should always = 0 volts and H to N should always = 120 volts. Therefore this confirms an open neutral.

2) In problems such as this, often it is a loose wire termination or a faulty wire splice.

3) Can you temporarily back out each of the 3 receptacles from the wall. But do not disconnect any wires. Perform a visual inspection on any wire nut splices in each receptacle box and make sure they are all tight. If any of the receptacles were wired using the back-stab inserts, those are always prone to come loose. The wires should be terminated to the side terminal screws. Double check all white neutral wires and the terminations to the receptacle silver screw (neutral connection)

4) Also shown below is a quick method that you can try by wiggling the 3 receptacles to locate a loose wire at a receptacle. Keep in mind that sometimes the wiggle procedure works and other times it may not work, but still worth a shot at trying.

Wiggle Procedure

You have a circuit with dead outlets and maybe some dead lights on it or you’re experiencing flickering on a circuit. You will need a 2 wire voltage tester to check the outlet. A Multi-meter or a Volt/Con are suggested. I prefer the Volt/Con because there are no settings to make, it does continuity and is audible. Success begins with knowing what you’re looking for.

1] No voltage reading between the hot and the neutral or ground indicates an open hot.

2] No reading between the hot and the neutral but 120V between the hot and ground and 120Vbetween the neutral and ground indicates an open neutral.

3] No continuity between the neutral and ground – Check for tripped GFCI device first

4] If all the branch circuit breaker are on you have a bad connection on the hot or neutral wires.The usual cause is a bad connection, either a termination on a device or connection in a wire nut.

Over the years I’ve found the easiest way to locate the opening needing examination and correction is to wiggle the devices.

5] The first step in this exercise is to get a lamp to act as an alert. Make sure the lamp works and in the on position. You may also use something like a vacuum cleaner or blow dryer, for an audible alert. Don’t use anything electronic, like a radio.

6] Plug it into a dead outlet.

7] Now with a cube tester or any plug you will need to go to all the dead outlets and any live outlets in the area, insert the plug and wiggle the device side to side slightly. Watch the test lamp or listen for the other alerts as you wiggle the devices.

If the loose or bad connection is present the wiggle action may make it contact briefly and the lamp or the other things will alert you . Having found the suspected outlet all that is left is to correct the bad connection.

If the device is a push back wired device, this probably is the cause of the circuit failure. All wires must be terminated under the screws. Also you should never put more than one wire under a screw.

This troubleshooting procedure works in most cases and won’t have you open boxes un-necessarily. Keep in mind that the problem is in one of two places in the circuit, either in the first dead outlet or the live outlet just ahead of it.

Reply back to me and let me know if you located any loose wire terminations or splices on the white neutral wires and we can take it from there.

Expert:  Kevin replied 1 year ago.

If you have any additional questions, let me know and I’ll be glad to answer them for you.

Otherwise,don’t forget to rate me before you log Off.

Thanks.................Kevin!

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