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Old 09-29-2021, 07:29 AM   #1
rockfla
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Default Calling all electrical experts

SO when checking a wire for continuity, IF the wire is "grounded" somewhere along its entire run, will it still read "continuous/continuity"? OR will the fact of it being grounded interrupt continuity??
Follow up question to above.......IF it shows continuity EVEN IF it is grounded THEN what would be the best way to test IF the wire is grounded (or shorting)???


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Old 09-29-2021, 08:25 AM   #2
Ken hash
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Default Re: Calling all electrical experts

If you have continuity from a wire to ground then it is connected or a short to the ground. Electrical problems can be challenging. Good luck
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Old 09-29-2021, 08:29 AM   #3
Zeke3
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Default Re: Calling all electrical experts

A wire will still show continuity even if it is grounded somewhere in the middle, as long as the wire is still intact. Check continuity between end of the wire and ground to see if the conductor is grounded somewhere.
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Old 09-29-2021, 08:36 AM   #4
fortyonerag
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Default Re: Calling all electrical experts

A grounded wire can still show continuity depending on how it happens, i.e. if you have a wire with a frayed spot touching say the chassis, you can have continuity between each end of the wire, but it is still contacting ground/earthed.

If you want to check if a wire is grounded, check the wires resistance to earth. If it is shorting, you will find it this way - low ohms to earth.

When you check the wire, disconnect whatever load is on the wire first (each end), or you will measure the internal resistance of what ever the wire is feeding. A lamp or a motor, say, will show resistance to ground, and this can be very confusing
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Old 09-29-2021, 09:01 AM   #5
big job
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Default Re: Calling all electrical experts

Oh my, forget all the math you need a test light clip the test light to battery + probe the suspected wire if the test light lights up that wire is grounded somewhere. Thats so common with cloth covered wires. So what wire are you dealing with?
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Old 09-29-2021, 09:17 AM   #6
koates
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Is this testing to do with your generator or cut out problem , or did you manage to fix that ? Regards, Kevin.
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Old 09-29-2021, 09:50 AM   #7
rockfla
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Default Re: Calling all electrical experts

Big Job - Its my wire from the ammeter to the generator


Koates - sort of but not yet, I am removing the generator & cutout and sending it back to Mike at Third Gen. He is the one who built it and talking with him a few weeks back he told me he had some issues with some parts awhile back SO he wants to get it back and make sure it is right!!! SO removing that this evening. I figured while Its off (OR maybe before I go to all the effort to remove and send it back) that I would "TRY" and check my wire and make "SURE" that its not grounded somewhere, somehow. DON'T see how as its a brand new wiring harness BUT stranger things I'm sure have happened!!! PLUS as you know from several months back, the nudnick that restored the car wired the generator wrong to begin SO wouldn't be surprised that he screwd this part up too!!!


This "Dead short" has been there since day 1 of delivery/pick up. LARGE popping and arching when you connect the hot side battery cable.

Last edited by rockfla; 09-29-2021 at 10:00 AM.
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Old 09-29-2021, 10:03 AM   #8
koates
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Default Re: Calling all electrical experts

If you like I can run you through a couple of very simple tests to prove a point if you would like. Regards, Kevin.
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Old 09-29-2021, 01:37 PM   #9
rotorwrench
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Default Re: Calling all electrical experts

It helps to have a long jumper if checking a wire that extends from the engine bay to the inside of the cabin when using an Ohm meter. If the wire is in an old style bitumen covered insulator sleeve then the sleeve would have to be damaged to short to ground. If there are other wires in the sleeve and they ever got hot enough to burn insulation then there can be a short between other wires inside there. Sometimes that is a short to ground and sometimes it isn't. It just depends on what other wire it may be shorted to.

A test light set up requires more power than an Ohm meter and may short out too when testing that way so be careful with that procedure.
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