ask the electrician
Electrician Training Electrical Certification wiring recessed light fixtures Electrical Wiring Electrical Troubleshooting and Electrical Repairs wire outdoor light fixture Home Electrical Wiring Diagrams
wiring home generator and transfer switch wiring a 220 volt range cord outlet Wiring for GFCI Outlets Wiring Outlets and a Switched Outlet Wiring and Installing Ceiling Fans and Remote Controls wire dimmer switch wiring diagrams for switches wiring a dryer cord and 220 outlet circuit breaker panel
Electrical Wire and Cable


What to do about Stray Electrical Voltage Readings

How to Identify the Source of Stray Voltage: Stray Electrical Voltage Readings Should be Identified and Corrected Right Away – Stray voltage is not normal and may originate from a faulty electrical or electronic component that could potentially become a serious shock hazard and cause damage to equipment.


Home Electrical Wiring Video

How to Wire a GFCI Outlet
without a Ground Wire

Check out my YouTube Channel and Subscribe to my Videos
» AskTheElectrician «

NOTE: A List of All my Helpful Videos
Will Display at the End of This Video
So Keep Watching So I Can Help You Wire it Right!

Sources of Stray Electrical Voltage

Electrical Troubleshooting Question: I have a single jet water pump motor, 120volt, on my inside spa that was wired by a licensed electrician 10 years ago. It has a dedicated circuit with a GFCI circuit breaker.

This home electrical repairs question came from: Bob, from Las Vegas, Nevada.

Additional Comments: This is a great reference site and I have it in my favorites, but I currently have an unusual situation not covered.

Dave’s Reply:
Thanks for your electrical troubleshooting question Bob.

How to Identify the Source of Stray Voltage

Bob, the indication of problems with the pump motor would be an indication and possible source of the voltage readings, however because the GFCI protection is not tripping this leads me to question the home ground system, please read on.

Skill Level: Intermediate to Advanced – Licensed Electrical Contractor, Not Recommended for Homeowners.
Tools Required: Electricians Pouch of Hand Tools.
Estimated Time: Depends on the extent of the project, the grounding method to be inspected and available access to the project area.
Precaution: If the only ground source for the electrical system will be modified or repaired then the electrical service should be shut off until the new ground source can be reconnected.
Notice: Making changes to the Electrical Service Panel and Ground Electrode System should be done with a permit and be inspected.

Stray Electrical Voltage Readings Should be Identified and Corrected Right Away

This Procedure will help Locate the Source of Stray Voltage

Pin Point the Stray Voltage Produced by Equipment or Connected Circuit Devices

Potential Sources of Stray Voltage

More about Electrical Wiring

Basic House Wiring Circuits
home-electrical-circuits

House Wiring Circuits and Circuit Breakers

This article looks at common 120 volt and 240 volt house wiring circuits and the circuit breakers that are installed identifying the types and amperage sizes used in most homes.
Electrical Panel Circuit Listing

Electrical Circuit Wiring
Circuit Wiring

Electrical Circuit Wiring

This article looks at common 120 volt and 240 volt house wiring circuits and the circuit breakers that are installed identifying the types and amperage sizes used in most homes.
Home Electrical Panel Circuit Listing

Home Electrical Circuit Breakers
2-pole-circuit-breaker

Home Electrical Circuit Breakers

A guide to home electrical circuit breakers and how they work to protect your electrical wiring. When properly installed, your home electrical wiring is protected by a circuit protection device.

Wiring a Spa Tub Circuit
hot-tub-wiring

Spa Tub Circuit Wiring

Electrical Codes and details for Spa and Hot Tub electrical wiring. Essentials for your hot tub installation, including the required GFCI ground fault protection and circuit wire size.

GFCI Wiring
Wiring a GFCI Outlet
This list of articles will help you learn about the features and benefits provided by GFI and GFCI Receptacles and how they are wired.

Using Electrical Testers and Voltage Meters
digital-tester

Understanding Digital Volt Meters

When working on home electrical wiring using voltage meter can play an important part in electrical safety. Electrical testers and voltage meters enable you to identify electrical circuits and help prevent the possibility of accidental electrical shock.
Types of Electrical Testers
Using Electrical Testers and Voltage Meters


The following may also be helpful for you:

Dave's Guide to Home Electrical Wiring:

» You Can Avoid Costly Mistakes! «

Here's How to Do It:
Wire It Right with the help of my Illustrated Wiring Book

Great for any Home Wiring Project.
  electrical wiring  

Complete Guide to Home Electrical Wiring

Perfect for Homeowners, Students,
Handyman, Handy Women, and Electricians
Includes:
Wiring GFCI Outlets
Wiring Home Electric Circuits
120 Volt and 240 Volt Outlet Circuits
Wiring Light Switches
Wiring 3-Wire and 4-Wire Electric Range
Wiring 3-Wire and 4-Wire Dryer Cord and Dryer Outlet
How to Troubleshoot and Repair Electrical Wiring
Wiring Methods for Upgrading Electrical Wiring
NEC Codes for Home Electrical Wiring
....and much more.


Learn more about Home Electrical Wiring
with my Online Video Course:
Basic Home Electrical Wiring by Example


Be Careful and Be Safe - Never Work on Energized Circuits!
Consult your Local Building Department about Permits and Inspections for all Electric Wiring Projects.

Electrical Tips to Help You Wire it Right

The Safest Way to Test Electrical Devices and Identify Electric Wires!

The Non-Contact Electrical Tester
This is a testing tool that I have had in my personal electrical tool pouch for years, and is the first test tool I grab to help identify electrical wiring. It is a Non-contact tester that I use to easily Detect Voltage in Cables, Cords, Circuit Breakers, Lighting Fixtures, Switches, Outlets and Wires. Simply insert the end of the tester into an outlet, lamp socket, or hold the end of the tester against the wire you wish to test. Very handy and easy to use.

The Quickest Way to Check for Faulty Electrical Wiring!

The Plug-In Outlet Tester
This is the first tool I grab to troubleshoot a problem with outlet circuit wiring. This popular tester is also used by most inspectors to test for power and check the polarity of circuit wiring.
It detects probable improper wiring conditions in standard 110-125 VAC outlets Provides 6 probable wiring conditions that are quick and easy to read for ultimate efficiency Lights indicate if wiring is correct and indicator light chart is included Tests standard 3-wire outlets UL Listed Light indicates if wiring is incorrect Very handy and easy to use.

Strip Off Wire Insulation without Nicking and Damaging the Electric Wire!

The Wire Stripper and Wire Cutter
My absolute favorite wire stripping tool that I have had in my personal electrical tool pouch for years, and this is the tool I use to safely strip electrical wires.
This handy tool has multiple uses:
The wire gauges are shown on the side of the tool so you know which slot to use for stripping insulation.
The end of the tool can be used to grip and bend wire which is handy for attaching wire onto the screw terminals of switches and outlets..

The wire stripper will work on both solid and stranded wire. This tool is Very Handy and Easy to Use.


More articles about Electrical Repair and Home Electrical Wiring:
« Previous Next »
Wiring Two Power Sources for a Submersible Pump Ceiling Fan With Flashing Light Problem


FAQs Frequently Asked Questions and Comments

2 Responses to “What to do about Stray Electrical Voltage Readings”
  1. Matt says:

    I recently installed two new circuits to my home 220 breaker panel to feed a new bonus room I’m building. One new circuit for will be for the lights, and the other new circuit will be for the outlets. Both new circuits are 20 amps with 12 gauge wire. In the breaker box I replaced two existing one-inch single pole 15 amp breaker switches with a one-inch dual switch 15 amp tandem breaker, thus giving me room to install a new one-inch dual switch 20 amp breaker tandem for the two new circuits.
    Yesterday I turned the new light circuit on and then turned the lights to the new room on and when I did a house fan with an electronic on/off switch (as opposed to a mechanical switch) that is plugged into an outlet on a completely different circuit on a different floor and on a different end of the house turned on “a little” – the fan rotated at about 10% of normal RPM. None of the new wiring goes close to the fan’s circuit until at the breaker panel where the fan’s circuit (single pole 1-inch single switch 20 amp) is located adjacent to the new twin one-inch 20 amp breaker switch I installed (next to laterally, not above and not below). The fan’s breaker switch was in the panel when I bought the house. The new twin 20 amp switch I purchased last week brand new from the store and is designed for my panel box.
    The fan on the other circuit only turns on when the lights in the new room are turned on. My guess is that I have an insulation problem between the two adjacent breaker switches, but I would like a second opinion and hopefully ideas on remedies.
    I appreciate your help!
    Thanks,
    -Matt

  2. Dave Rongey says:

    Hi Matt,
    This kind of electrical troubleshooting is always fun. I’m wondering if the house fan has been working fine before the new wiring has been installed and your description of the occurrence? With that question in mind, I would place the circuit breakers back to the original configuration and test the house fan for proper operation.
    Another test to perform to see if there are two circuits that are possibly looped together can be identified by turning off all of the circuit breakers with the exception of the main breaker, then turn on one circuit at a time and see if there is voltage on the wire terminal of any other circuit breaker that is in the off position. If this happens to show up then one of the two circuits must be taken off of the circuit breaker. This condition where two circuit breakers that feed one circuit will not trip the breakers when the circuit breaker’s power source comes from the same main buss, otherwise if each were on the opposing buss there would be a direct short.
    Dave