Electrical Wiring in the Home/Light Wiring in Attic



We bought a house that has a fluorescent light wired in the attic, operated by a light switch (which looks like that switch may be operated by another light switch. It has not worked since we bought it. I replaced the bulbs, thinking maybe that was the issue. How can I tell if it has something to do with the fixture or the wiring?



So you think this switch is a three way?  Three way switch circuits have two switches at two locations when there is say  two entrances to a room,    if the switch is a three way switch it will have three wires and a ground,  a bare ground wire,    ground is not critical to operation it is for safety  so if there is no ground as many leave grounds off switches   if there are three insulated wires most likely two of one color coming from the switch it is likely a three way switch,   and either the other switch is bad, or this one is bad, or both or bad, or no power to either,

First thing find the incoming power   then find the load side which goes to the light,   get a voltmeter   you will need a meter that reads voltage value not a non contact because we are looking to see if you have somewhere near at least 110 volts going to the light,     

switch legs are just the hot wire run to a switch where the switch "cuts" the wire into,  that is all a switch is,   a three way has a traveler wire from switch to switch and then power,  so the light or load can be operated from two places,    

Quite often the first thing that fails in a fluorescent light is the bulbs but they should appear blackened and some fixtures fail if just one bulb goes out,  so  measure the voltage at the LIGHT   is there 110 or so there?  When you flip the switch does the 110 go away?

If so bad bulbs, bad ballast, bad wiring in the fixture,   for a temp test,  unwire the fixture find a cheap ceramic fixture with a known good bulb   tape it up good  with lots of black electrical tape   and see if it works,      again bad fixture buld ballast     if no voltage now you have some detective work,   but first determine if the switch has more than one wire on each screw  if there is three   find the other switch and again measure for voltage,  I get questions all the time about things like this and there is another switch hidden behind a cabinet or something,  but that alone should not keep the light from working,  

Butyou need to find it anyway     because it might be that the other switch is bad,   but if you just have two wires it is not a three way,     

Now you look for any loose wire nuts in any boxes   the switch box the light box   check the breaker     look for a GFCI that may be tripped somewhere,   but you will need a voltmeter and be working with live voltage,   if you feel uncomfortable with that,   hire a referenced electrician.       

But you said you bought a house    when?     Most homes have to pass an electrical inspection  what happened then and when,?   Can you contact the seller or realtor  sometimes they will be very helpful and maybe provide the answer over the phone,     most likely you have a bad light fixture bulbs or something,     but until you can prove there is power  or you can get another power supply to the fixture and then it works,     ??  The last one will be the most difficult,  the simplest of all is to get a cheap single bulb fixture, you know the older style for like a crawl space   they still sell them or find one at a swap shop,     wire the two wires at the not working fixture to the new buld and fixture and see what happens    it either lights or not,   if it does  bad fixture,  if it does not  something somewhere is open  the switch is bad,  the OTHER POSSIBLE SWITCH is bad, or some wire nut came loose,    check your breakers make sure none are tripped and if one is   and it resets   great     and all works,  but if it is tripped and when you go to reset it      it trips right back off  or will not reset     call an electrician  that is a problem way beyond diy  and diy in electrical is not my most favorite advise      only if you have experience and are comfortable with a meter and live power should you even attempt diagnosis,    a good electrician should have this kind of thing diagnosed in a matter of minutes,    if not  then get another electrician     

And if they start telling you stuff that makes no sense with big $$$ write me back and I will call them if needed,   this should not be a big deal      one switch  one fixture   minutes if that     now they have minimum charges for a trip charge and honestly if the price is reasonable that is fair     for the gas the service vehicle and the time     but maybe you know a handy person who can look at this who is experienced with electrical,     people find me all the time,    I am sure there is someone around your cirles that can diagnose a light fixture and switch         let me know how it goes      and get references if you go with a company and another thing,  do not just let them show up,   you go to their office or shop and look yourself,   the days of fake websites is here to stay and many websites look way better than the real building and company   so check their place before they come to yours  
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Electrical Wiring in the Home

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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 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,


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,

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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