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Electrical Wiring in the Home/dim lights and 220 appliances won't work


QUESTION: I have 240v coming out of the meter box, both above and below the 200 amp main braker, with all brakers off inside,I have 120v on one leg and the other leg is dead,with all brakers on inside, have 120v across one side and 100 on the other leg.All 220v appliances will come on but do  not have enough power to heat up,while most lights in the trailer are dim.Is  my problem with either my main braker outside/inside

ANSWER: Walter  look at the main breaker,  look for a bad earth ground, or a high resistance connection on the side with the low voltage,,      

I think you are telling me no load     you still have low voltage on the one side,  so it is likely the main breaker has bad contacts, or a connection to the buss,.      either way  you need to find where the voltage is dropping on that low side        it could be anything from a bad connection to the main being bad,        

I am not understanding if you are losing the voltage on the one side when all single pole breakers are on,     

It could be a short on one of the low voltage side circuits,         

The 220 appliances should not be operated until you find the problem   one of the hot side legs is low making the voltage at the 220 out low,   

Try the breakers     with meter on,     below main,   one at a time    if it drops when one breaker is flipped on   that is the place to look   but look it all over  it could be two problems not just one,          

After you turn it on,  with meter below or on load of main,  one at a time flip on breakers ON THAT SIDE  watch meter  and try to identify one circuit that is sucking the power out   

Then let me know what you find,   

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QUESTION: Just to let you know,the outside box connected to the meter only has one breaker,the main,all others are inside in that box.Also a new piece of info. is I have taken measurements across the lugs inside and out and found that I have 250v across the main outside and only about 10v-20v inside across the lugs.I looked for a loose ground connection and all is secure. I also started checking the 110 breakers, one at a time, and found that when I turn off a 15amp breaker,the lights became bright and the voltage went up, but only to 100v across the lugs, so that might be part of the problem,but not the whole problem.I would like to take the time to thank you in advance as this has me stumped.I initially thought it was the main,but with 250v on the lugs and bus bars above and below the main,I started to second guess myself,so any help I can get will be greatly appreciated

ANSWER: Walter,  you have line side of 250 before the main,  then you have a load side of 10- 20 Volts, when you turn off "A"   [Which one?] breaker, the voltage goes up.

Remember these problems can be "backfed"  and open neutrals, high resistance connections, can show a variety of confusing readings,

These can be from the utility feed, the meter, the outside ground rod, or stake or grid, the main,   ANY CONNECTION    ANY INDIVIDUAL CIRCUIT     so GO SLOW

You really need a way to measure current with some sort of clamp on amp meter as well as a volt meter   and make sure the probes and leads from the meter are in good condition,    

And be very careful,  if you feel it is over your head it is over your head,   call and get professional help!

So you are dropping voltage severely at least one individual breaker,       will the voltage raise if you open ANY breaker?   Or just the one?

Open circuit voltage and loaded voltage are two different issues,   

You know you can carry the voltage across the main and you know you can carry some current across the main because you proved it, by opening one breaker,    if you open more breakers [randomly] does it get better and better?   

You need to see if every breaker has the same effect,     one at a time,

That way you will know if it is one individual circuit that is shorting or carrying a very high load for whatever reason,    or if any ONE breaker helps,  it may be the contacts in the main breaker,  but it is likely a problem with something besides the main breaker.

Try and reset it several times.
Next    open all breakers with the volt meter on the load side at the lugs,   

Take readings as you CLOSE each breaker one at a time,      much easier than having the breakers closed.  

As you close one breaker at a time,     if you get the same results from each breaker, all doing the same thing,  then you look for a main problem or neutral problem or ground problem  

If you close one breaker and nothing happens    then keep going until you find the offending circuit,

Before going any further read below,   I could go on for pages, but not being there, knowing it could be back feeding and giving you false negatives,    it is a situation you need to understand as much as possible,     IT IS NOT AS STRAIGHT FORWARD AS IT SEEMS



If these help you and you are confident to move on    then let me know as you go what you find and where       but do it in a methodical manner,    when testing I need to know which breaker,  if all act the same,      remember the "good" side could be as much of the problem as the "obvious" side,    because of back feeding and only reading voltages,  EXAMPLE

---------- FOLLOW-UP ----------

QUESTION: I am at work right now,but while here I had my wife to call out POCO and the problem was not on their side.When I get home I will check all neutral and ground wires.I will say this,with all breakers off and the main on I had one dead leg.The first thing I will check when I get home will be the three wires leading from the meter loop to the house to make sure that no animals have chewed any incoming wires,I couldn't do this before on account of rain.A couple days ago I checked like you said,one breaker at a time,but can't remember the out come.i don't think I found anything suspecious,but i will redo that test after checking neutrals and grounds!

Wait you got one dead leg,   you mean one hot side is open,  to ground to neutral to the other hot?

On the load side forward of the main breaker?

That is a huge problem,,    not necessarily expensive huge,  but huge as to the problems,    

Turn all breakers off     

Do you have a clamp amp meter?   You can get a decent one at a hardware store,    or borrow one or get one in a pawn shop       it is a amp meter that has a trigger that opens two clamp halves,  you put it around a conductor and measure the AC   AC CURRENT    

NOW we are at the main, main is open off     all breakers below flipped off,     

There should be no voltage or current from the load side of the main breaker.  It is off  [we are looking for leaks]   

Now flip the main on,   measuring for voltage  hot to hot,  hot to neutral hot to ground ......... hot to ground  hot to neutral from other side  what do you get, ?

Then reset that main a couple times,     flip off   rest   30 seconds  flip on rest 30 seconds, about a couple minutes worth   4 or 5 flip/on/off.  A few minutes.   Remeasure,   what do you get?  Write each measurement down,     remember I cannot see what is going on,  

Get a yellow notepad,   just put settings as a header   

Under headings  you put    Main open all breakers open   then draw a column  header,  line to line voltage at load side of main   if it is 0 put 0     new column  same conditions   side one hot to neutral  put a volt value in there,      to ground  put a volt value in there,   

Now another column   [call them side left hot, right side hot]  so I get a physical picture,

Same measurements,     

Then leave room for more blank columns below those,        close number one breaker left side,  fill in data     fill in data for right   [I know.  it shouldn't matter but trust me]

Do the same thing,     for the other side  which would be top breaker right side,    

Then go down the rows of breakers,  once you test one sub breaker  open it,   move down to the next breakers,   write in data,     that should give you a complete evaluation of voltage at least  all the way from main to the very last breaker,   

See where I am going?

Get that to me as soon as possible

You got an open somewhere and someway some backfeeding is going on,   that seems to fit,    

Find the open    now it could LOOK closed it could look tight,    It could look perfect but be open,   a high resistance corroded connection would produce heat,     if you have a thermal gun  shoot the whole box,   borrow one or rent one dont buy one,  

Don't feel around  keep your hands out of there,

How old is this home ?    Has it had circuits added?   By whom?   When?

Do these things and report back    use my personal email   subject  allexperts volt drop main,        then I know it is you,    much faster,      then we will move on, to find this problem,          I need exact voltage readings   and descriptions,   in other words,       breakers all closed,    measuring at load side of main breaker,  do you have no volts  .2 volts,  whatever it is,     

When you measure     from one hot to ground,   breakers all closed       what do you get?

Nothing?     Now the other side.     Same measurements,  

Now all single and double breakers OFF  

Close Main   repeat as above with breaker open,  
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Will Babbitt


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 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. 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,


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 Evaluation and repair of electrical/mechanical apparatus. Electrical and mechanical repairs, trouble shooting including, vibration and balance issues. 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,

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


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.

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