Electrical Wiring in the Home/VOLTAGE DROP

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Question
AT THE CIRCUIT  BREAKER IN THE PANEL BOX I'M  GETTING  A GOOD  READING  OF 124VAC  HOWEVER  THE OUTLETS IN THAT CIRCUIT I'M ONLY GETTING  73VAC.  I  DONT KNOW WHERE  THE VOLTAGE DROP IS COMING FROM OR HOW TO FIND IT.  I HAVE ALREADY  LOOKED INTO  THE OUTLET  BOXES FOR WIRE NUT  ISSUSES OR BURNT TRACKS BUT HAVE FOUND NONE.  I HAVE ALREADY  REPLACED TWO OUTLETS AND WILL BE  SOON  REPPLACING  THE  OTHERS  TO  SEE IF THE OUTLETS ARE  SHORTED  OUT  INTERNALLY. PLEASE  HELP  I HAVE NEVER SEEN  THIS  ISSUSE  BEFORE

Answer
Robert,  I take it this phenomena came on suddenly,       anything noticeable that changed,  storm, brown out, black out,  power outage,  overload on something that tripped a breaker?

Any history before you found this problem would be a help, we need to find the root cause, so the problem does not come back,    

It doesn't sound like a voltage DROP    it sounds like some sort of open or intermittent open neutral connection somewhere,      

So this is not a problem on the entire supply, just one circuit?  Correct?

Sounds like you have done the visual,  on all the effected outlets,  anything else on that circuit?

A good tool would be a non contact voltage meter,  a large pencil looking device,   that you can use to trace where the voltage stops or drops,  while the meter does not have a meter, it simply beeps,  but you should be able to trace most of the circuit,  behind sheetrock  so on,   the tool is not expensive and for electrical problems is a great tool to own,     

Without me hand listing the steps  I am going to provide you with a link,   please read the intro, then drill down to your specific problem and follow the trouble shooting steps,   

Since you have only one outlet that does not provide full voltage across hot and neutral then this outlet is a branch end. So unless you have an illegal hidden junction box or the very unlikely broken neutral wire, the bad neutral connection is happening at the outlet upstream of this one going back to the breaker distribution panel. This outlet might be on the other side of the wall or along the wall in the direction to the breaker panel.

A common problem that fits your symptoms was that at one time outlets were permitted to have spring loaded knife edges to make a connection to a bared wire. Over time these springs would fatigue and stop making a good connection. This design did save an electrician a little time in wiring a house. But over time these weak springs could and have started more an electrical fire.

If you have a hidden junction box though, then you will likely have to remove some sheet rock.

The point above is to check switches also,  and for the price of new outlets,  spend little time on diagnostics of the outlets,  keep them and examine later, but start at the first apparatus you can identify be it a switch or outlet, and replace it,     

Now for the diagnostic steps   :

http://www.thecircuitdetective.com/


Go the website above and read through it,  very short read,  then follow the steps one at a time, be prepared to replace outlets and switches,   also if you find several,   maybe consider replacing all outlets in your home or wherever this is,   if the failed circuit is worn out or failing outlets or switches,  I would consider replacing all of them as you can,  no reason to poor a bunch of money into all new breakers at once, ONCE YOU CLEAR THE IMMEDIATE problem,  but after that,  and a close look at the offending devices if that is the problem,   get a good grade of new outlets to prevent this from happening on another circuit,

The Circuit Detective, due to rising costs [I have NO affiliation with his site but it is done well,  may need to charge 10 bucks,  it is worth it,  as you have diagnostic trees or yes no answers,  whatever you are more comfortable with,  but the 10 bucks is damn cheap for a well thought through site,,,,,,,,,,,,,,if you just cannot find the problem,  get back with me,  my company is MEAR Services in Kansas City,  repair@mearservices.com   as long as we are not on the phone for hours and hours we are happy to help no charge,     

William Babbitt  
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Electrical Wiring in the Home

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Will Babbitt

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Electrical issues of all types, wiring, control, appliances, components, specialty in Electric MOTOR or APPARATUS trouble shooting, electric motors, electrical problems, single phase, three phase, DC, capacitors, elevator MG-Sets, modifications, reverse engineering, VFD Drives, single to three phase convertors. Repair of most any electrical/mechanical/electronic apparatus, OEM, AC, DC, Industrial Applications, Three phase, single phase failure mode, determining the root cause of the equipment failure BEFORE failure repeats, Antique appliances, electric motors, fans, ceiling fans, base mount fans, poor equipment performance, Modifications, habitual failures, vibration, redesign, obsolete issues, collectible items restored, rewinding. Owner of EMR Repair Inc www.emrrepair.com More information on electric motors, under Engineering/Motors Ask about any electrical or mechanical problems in the home, office, or even at your work. B2B or business to business CONSULTING I can do but it would be a much more complex issue, that would require a significant amount of time. repair@mearservice.com from there we can discuss and begin work on about anything. Industrial electric motors, controls, troubleshooting, vibration, alignment, any type of industrial or commercial electric/electrcical equipment For the home owner, renter, apartment if you have odd things going on, describe to me, photos are normally very helpful, appliances, heating and air conditioning issues, light switches, installation, DIY PROJECTS FOR THOSE NOT EDUCATED IN ELECTRICAL, we can do some things, but for safety and sanity reasons, I may refer you to a local electrician, and help you find one, help you with pricing and even speak directly with anyone you hire if you have issues,

Experience

Over thirty years with a major repair and sales company, VP of Operations, and former owner of my own specialty repair shops, MEAR Services local to Kansas City Missouri EMR Repair Inc., located in Kansas City Missouri, 2014 sold both businesses to JCI Industries, Lee's Summit Missouri wbabbitt@jciind.com Evaluation and repair of electrical/mechanical apparatus. Electrical and mechanical repairs, trouble shooting including, vibration and balance issues. About.com provides this service, and the huge costs to provide help on about any subject. They provide the servers, the people to vet the experts, costs that would be the same as operating a good sized business, They should be appreciated for what they do, the huge costs and the great help they provide for free, Electric motor questions, can be answered here but there is a dedicated category that has other experts to help and add to a solution. Other common questions, are noises in the walls, breakers tripping, devices not starting or shutting down for no apparent reason, smoke alarms buzzing, thermostat change outs, or sizing wire or needing information for a new project, but anything can be resolved, anything, with enough effort and patience, DIY, with electrical is possible, but in most cases the use of a simple ohm meter or volt meter is needed, they can be purchased at any hardware store for a few bucks. If you have smoke, or smell smoke, don't be writing me, call 911 the Fire Department has no problem looking for smoke smells, better then spraying water on a blazing fire. DO NOT GET CAUGHT INVESTIGATING AND TRAPPED IN A BASEMENT LOOKING FOR A BLOWER FAILING< As to the tip jar, it is up to you, it is appreciated, every expert spends out of pocket that I know, we spend on IP time, computer wear, printing documents, books, and of course our time, but if we prevent a $400 service call, we did well,

Organizations
Former IBEW, EASA, IEEE, UL, ..............

Publications
SEE ELECTRIC MOTOR CATEGORY

Education/Credentials
10 plus years, various Technical Schools, followed by Industrial College Credit and non Credit Courses, electronics courses, experience in most any electrical apparatus, electric motors and generators, AC OR DC, fractional to above 5000HP, other electrical apparatus, slip rings, sleeve [plain] bearings, lubrication, identification-no data plate, control components, service and sales. I have continued night schools for decades, the list is extensive. I have been in the business of repairing most anything with wires or mechanical parts for decades, I have some helpful hints and directions you won't have to dig up. Or hopefully not have to pay a huge service call invoice to find.

Awards and Honors
Yes

Past/Present Clients
Federal Government, National Weather Service, NOAA, Commercial Power Plants, Major Vehicle Manufacturers, Printers, Other industrial and Commercial Businesses

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