Testing for short circuits

gm280

gm280

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Re: Testing for short circuits

That would depend on what type circuits you are wanting to test. A good quality DVM, VOM, or good volt/ohm meter is the number one tool most technicians use for most testing issues. The tester you posted about is used to isolate wire runs through walls and such. It introduces an audio tone to the wire your searching for and you take the receiver and trace it through the walls to where it goes. Could be used for other testing, but I'd take a quality DVM any day. But that is JMHO...
 
bruceb58

bruceb58

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Re: Testing for short circuits

This won't test for short circuits.
 
Cofe

Cofe

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Re: Testing for short circuits

bruceb58 said:
This won't test for short circuits.
Click to expand...

According to this video, it does test for short circuits. How to find an open circuit or shorted wire the FAST easy way - YouTube

What I am looking for is something that will find a short in a wireing harness without poking holes in the insulation to probe. I am familiar with using a multimeter for testing a harness, but I would like to find something that would pinpoint the break or short, and it looks like this device would do that.
 
bruceb58

bruceb58

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Re: Testing for short circuits

Please tell me where in the video where it shows where a short was found.
 
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DXN

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Re: Testing for short circuits

I've been a tech for >6 years In my experience there is just no compromise for a good meter, I hate it when the other techs poke holes through the insulation then the wire corrodes and I have to fix it down the road. I told my guys not to ever break the insulation and ordered retractable Leeds for everyone they are like 20 ft long and you can put alligator clips on the terminals. Makes everything easier. They can be kinda price but harbor freight has some cheap ones that work fine... Well they used to I tried to find them for you. But these test leads from NAPA are guaranteed to make life easier.
Retractable Wire Test Lead SER 1129 & SER 1137 - YouTube

I've seen guys try to use those circuit sniffers, and they didn't have much success in the end they put it back down and went back to the meter.
 
Cofe

Cofe

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Re: Testing for short circuits

bruceb58 said:
This won't test for short circuits.
Click to expand...

I think what bruce58 is referring to is that in a short circuit, some voltage may get by the shorted portion of a wire. With the tone generator, it wouldn't register because the tone would be heard past the shorted area. In the event of a dead short, the device should work. I am only speculating about this, because I have never used one or know anyone who used one.
DXN makes a good point about getting longer leads for a multimeter. Then a person could test for voltage drop along the full length of the harness.
 
bruceb58

bruceb58

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Re: Testing for short circuits

If you really had a short, you would create continuity on 2 wires so this tool wouldn't help you at all. I see how it might help you with an open and find where in the path it would be open.
 
Grub54891

Grub54891

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Re: Testing for short circuits

I have a similar tone generator, not good. $80.00 wasted.Another workmate has one that works pretty well, but I don't remember the brand. I'll have to check what it is.
Grub
 
U

UncleWillie

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Re: Testing for short circuits

I use one at work. Telephone company.

They are for circuit Tracing not circuit Testing. "Extech... Circuit FINDER Kit."
If you have a cable run of a group or unmarked wires you can use it to locate the wire at the other end.
Then you break out the real meter to do the actual testing.
It will be useful in Locating the wire you already know is Shorted, but not for locating the Short in the Wire. (Read that Sentence again Closely!)
If the Wire is shorted to another wire, Both wires will tone.
If the Wire is shorted to ground, the tone will be heard EVERYWHERE.

At 0:49 in the video he refers to where the harness is CUT, That is an OPEN not a SHORT.

It serves its purpose in the Telco and Computer world and can be used to locate a breaker in a panel without flipping all the breakers until the lights go out.

On a boat with a color coded wire harness, it will only be a novelty.
 
bigdee

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Re: Testing for short circuits

bruceb58 said:
If you really had a short, you would create continuity on 2 wires so this tool wouldn't help you at all. I see how it might help you with an open and find where in the path it would be open.
Click to expand...

I'm with bruce. Individually ringing the wires one at a time with each of the rest of the wires on the same end with a multimeter is the best way to find a short. Checking opposite ends will find open circuits.
 
dolluper

dolluper

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Re: Testing for short circuits

one connector to another on Ohems high reading short replace that wire ....why waste time searching for break
 
bruceb58

bruceb58

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Re: Testing for short circuits

dolluper said:
one connector to another on Ohems high reading short replace that wire ....why waste time searching for break
Click to expand...
You mean open right? Not short!

Never seen Ohms spelled that way! :)
 
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