Electrical Wiring in the Home/shock from compressor


Hello, have a question about getting a shock from my air compressor.  My son bought me an air compressor ( Snap-On ) portable.  He plugged it into a 100 foot 12GA extention cord and plugged that into a CGFI outlet.  When he went to open the drain on the bottom of the tank to drain any moisture from the tank he got zapped.  
 I checked the outlet with one of those CGFI specific outlet testers and it showed the outlet was wired correctly. Yes, before you ask I did the installation of the CGFI outlet.  Though it was only changing the receptacle from a none GFI outlet to the CGFI outlet.
 I used a continuity tester to check for a short on the motor cord plug.  I got no continuity between the ground terminal on the plug and either of the two flat plug blades. Nor any continuity between either plug blade and anywhere on the tank or motor.  While I don't know a lot about electrical wiring I do have an Electrical Code Wiring book ( The Green One ) and use it all the time when upgrading my electrical.  
 About my house:  I have a two floor eight room house that has tree trucks as floor joices. a separate four car garage, a separate small workshop AND a separate horse barn.  All on 4 circuits. At least it was until I installed a 40 circuit breaker box and started re-wiring, and adding circuits as I've remodeled. ( An on going slow job )
 I'm looking for ideas as to what is causing the problem. I've kind of run out of possible ideas and friends to ask.
 I drive for a living and am only home weekends, so if you need additional information it might take a day or two to get an response.

I.m not big on DIY electrical  and when some one gets zapped it is no time for school,   it is time to get a pro    period      not worth the problems that could be even worse  have someone come and diagnose the issue   

Shock is nothing to be fussing with      with no equipment and meters       it is well worth having a pro electrician check it all out  
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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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