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Here's another use for a NCVT. One of my lineman buddies keeps a Fluke NCVT (tic-tester) turned on in his shirt pocket while walking through the woods looking for downed power lines after storms. He says in this position it will start beeping at him from up to 10 feet away from an 11KV line, which always makes him stop in his tracks.

I've never tried this for myself, but it would be an interesting experiment. I'll be sure to video it if I get around to testing this, but I'll need a lineman to energize a high-voltage line on the ground to try it out.

That would be kinda cool...:eek:
 

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Mad Skills
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NO I am not.
You are...and you are still defending your work practices.

I posted a way I tested for voltage on a conductive surface.
You posted a good way to get someone/thing hurt - and that is all.

That is not how a professional works.


To each his own.
?

...If you don't give a rat's ass about yourself - fine.
What about the person or pet that comes in contact with you?
Their family?
YOURS???

Let's end it at that shall we?
I've always been brutally honest with you - I'm not about to stop.

Gimme your address, I'll mail you one.
I'm not sorry if you take offense....you need it.
 

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Discovered something like this in old house in inner suburban Sydney that looked like something out of a Dracula movie,false battlements,gargoyles,etc,looked out over an old graveyard,anyhow we got called by this twat of an inspector for DLO cables used for consumer mains,no earth stake,no neutral pulled for HVAC,didn't need it,mulitap trans used for controls,blew his wad bout other ****,one thing this college boy type missed,bodgie earths on most outlets cept one,an old hubell twin crowsfoot,type of pin arrangement used since 1937 in OZ,ground contacts created by bent copper shaped and riveted to the bakelite ends screwed to the steel box,whole house wired in black screwed pipe.In 70s some clown replaced these with switched HPM twin GPOS,strapped ground to the noodle,customer said they got funny tingles in kitchen and laundry when using high current appliances,3kW fan heaters,dryers,daughter said we have to pull earth wires or new TPS,(Romex) I said no, we do an impedance test on the pipe,wiring to all outlets was 10 awg approx, 12 for lights,with 3v from our variac/step down trans,800A to furthest outlet so we pigtailed the ground to the boxes,tingles gone.
 

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So explain how my method jeopardizes the safety of my customers.
aftershockews, let's please not get into a semantic tussle over this. So I will concede that testing your way should find a hot-ground situation and not endanger the customer, but I still think it's a bad idea from a personal safety point of view.

For example, when I was a young-pup Industrial EE back in the 70's, one of my shop electricians would test for 120, 240 or 480 volts on a wire by touching his thumb to the conduit and brushing the "test" wire with a finger on the same hand. By seeing how high his hand jumped, he could gauge the voltage. Now this was the days of solenoid testers, and we always had one in our work cart. But he liked to show this off to the young engineers. I was NOT impressed since I knew that one wrong move on his part would have killed him. I told him to stop it since I didn't want to have to fill out the paperwork if he died on my shift while working on a machine for me. But he claimed to have done this many hundreds of times without injury. One mistake and he would have been dead.

There was also an engineer in our sister plant doing essentially my EE job, and he died while showing management where an electrician the previous week had snagged an insulating glove on an 11KV line and was injured. However, the engineer pulled a pencil out of his pocket and poked it right at the energized lug, which killed him on the spot. And he was a mature engineer with 20 years experience, but just made a mistake while discussing this with his boss. I NEVER let anyone talk to me while working around live conductors. One second of inattention could be deadly.

After those two events I was REALLY careful around electricity since I began to understand how close we put ourselves to death on a daily basis. The only thing that keeps us safe is by following safe practices out of habit. Once I have to go out of my comfort zone, I get REALLY careful and focused.

So even if what you do has been safe for hundreds or even thousands of times, one mis-step on your part or a failure (short) in your test gear could be deadly. And you certainly don't want to pass this dangerous procedure on to any apprentice electricians you may be training.

So let's stay on topic about measurements and such. And let's all live long and productive lives so we can share a beer someday and talk about the crazy stuff we've done and seen.

Mike Sokol
 

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Rest In Peace
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You are...and you are still defending your work practices.


You posted a good way to get someone/thing hurt - and that is all.

That is not how a professional works.



?

...If you don't give a rat's ass about yourself - fine.
What about the person or pet that comes in contact with you?
Their family?
YOURS???


I've always been brutally honest with you - I'm not about to stop.

Gimme your address, I'll mail you one.
I'm not sorry if you take offense....you need it.
I will dissect you're response when I am not posting from my phone.

And I do not take any offence from your replies because they are constructive and not destructive .
 

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felonious smile.
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I just use GFCI devices or breakers depending on the amount of replacements of 2 prong receptacles involved.
 

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RIP 1959-2015
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Discussion Starter · #69 ·
That was an insert to an article that ran in this months EC&M on bootleg grounds. Problem I have with that article is the author gave examples on why plug in testers lie but in the last paragraph the only way to test for a bootleg ground is to use a tic tracer. Wtf? Id trust the plug in tester a hell of alot more than the tic ESPECIALLY the way the author describes to use it.
I don't see that in the last paragraph .?
 

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I still don't get how a tic tracer is going to tell someone a receptacle has a bootlegged ground. All it does it sense AC voltage.
It won't detect a bootleg ground with the incoming neutral and hot lines correctly wired. But it WILL detect a bootleg ground with the incoming neutral and hot wires reversed. That's why I call it a Reverse Polarity Bootleg Ground (RPBG). It's hard to wire this by accident in modern wiring, but surprisingly easy in pre 1970 wiring without grounds.

In an RPBG situation, the neutral and ground contacts are at 120-volts above earth potential, and the hot contact is at 0-volts. This strange condition will read as correctly wired using a 3-light cube tester or a voltmeter between H-N, H-G and G-N. Even using a ground impedance tester such as an INSP-3 or SureTest won't identify the reversed polarity condition, though it WILL find the bootleg ground.

What makes an RPBG so dangerous is that ANYTHING you plug into it with a grounded power cord will have its chassis electrified to 120-volts and full circuit breaker current. And there will be NO sign the appliance is electrified, since it will operate normally. This RPBG outlet can exist for years or even decades before someone touches something plugged into it and anything grounded at the same time. Then it's very likely deadly.

My point is that by adding a simple NCVT check to your standard outlet testing (especially in pre-1970's wiring) you may find a potentially deadly RPBG mis-wiring condition and save a life. And that's a good thing.

Does that make sense?
 

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That is the most bizarre situation that would be the last thing on my mind, while actually working as an electrician.

So ONLY bootlegged grounds that aren't even bootlegged, because they're just completely wired wrong, can be found using a tic tracer?

What does the tic tracer do differently that distinguishes it as an improperly bootlegged, bootlegged ground receptacle? I'm supposed to walk through houses waving my tic tracer in the air, 2 feet away from receptacles, to see if it'll find these one in a million wrongly wired receptacles?
 

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So ONLY bootlegged grounds that aren't even bootlegged, because they're just completely wired wrong, can be found using a tic tracer?
Well, it actually IS a bootleg ground. But the white and black wires were somehow swapped in the walls somewhere. I've seen this in a lot of old K&T wiring since everything is black, and many times the neutral was switched for lights and such. Those were crazy times....
What does the tic tracer do differently that distinguishes it as an improperly bootlegged, bootlegged ground receptacle? I'm supposed to walk through houses waving my tic tracer in the air, 2 feet away from receptacles, to see if it'll find these one in a million wrongly wired receptacles?
Well, I think that an inspector is "supposed" to check every outlet for proper ground or a GFCI, using a 3-light tester at the very least, and a SureTest or INSP-3 for commercial installations such as hospitals. However, that's probably wishful thinking on my part.

The reason why a tic tracer can find a REVERSE POLARITY Bootleg Ground is that the outlet now has it's ground and neutral energized to 120-volts with a low-resistance connection. So if you happen to be measuring an outlet due to a customer complaint about sparking or feeling a shock from an appliance, then the tic tracer (NCVT) will tell you what's really going on with the outlet in a few seconds.

Remember, standard voltage metering between H-N, H-G and G-N will NOT find a bootleg ground of any kind (unless you load the circuit and look for a voltage change between G-N). And Ground Impedance testers (INSP-3 and SureTest) will NOT tell the difference between a Correct Polarity Bootleg Ground and a Reverse one. And I've seen a few extension outlets added onto the end run of a RPBG outlet, in which case there is no visual or operational difference between an RPBG and a 100% properly grounded outlet. Except that the RPBG has electrified the refrigerator or microwave chassis to 120-volts.

I only present the idea of using a tic-tracer to look for hot outlet grounds as one more troubleshooting tool when looking for wiring mistakes. Thinking back over my 40 years of electrical work, I can remember dozens of situations in rental units and performance stages where there were shocks that I didn't understand, and this would have explained it all. In fact I first found an RPBG outlet in my dad's rental property in the late 70's right after a housing inspector validated all the wiring after a reno. The guy renting the place said he was feeling a tingle from his air conditioner while standing on the concrete floor, so when I measured from a water pipe in the bathroom to the ground in the outlet, I found 120 volts. Inside of the new grounded outlet was a G-N jumper. Of course it was old K&T wiring where everything is black so the contractor "guessed" which was white and black.

I also found a RPBG outlet in a church just last year where I was teaching a sound mixing seminar with 20 mixing boards on the desks for students, all of which were plugged into a "new" outlet on the wall. Everything worked properly without any hum or buzz in the sound sytem, but when I got my Fluke VoltAlert near any of the mixers, it started beeping. I found that the "new" outlet was part of a reno that some of the church members has helped with. And, of course, rather than run new wiring through the concreted block walls, they just did a bootleg ground to "upgrade" the outlet. While none of my students would have been shocked since they were all on a carpeted floor, if anyone in the corner would have touched the metal surface of a mixing board while leaning against the metal radiator cover (grounded, of course) it would have shocked them, and possibly resulted in death by electrocution. Not something I like to see in my seminars.

So now I'm always suspicious of the "new" outlet in an old building. That's where RPBG outlets are a real possibility.

Mike Sokol
 

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That is the most bizarre situation that would be the last thing on my mind, while actually working as an electrician.

So ONLY bootlegged grounds that aren't even bootlegged, because they're just completely wired wrong, can be found using a tic tracer?

What does the tic tracer do differently that distinguishes it as an improperly bootlegged, bootlegged ground receptacle? I'm supposed to walk through houses waving my tic tracer in the air, 2 feet away from receptacles, to see if it'll find these one in a million wrongly wired receptacles?
No...what he is saying is if the neutral and hot are switched on a receptacle and then someone bootlegs the ground (to the hot now) you will have 120 volts on the on the ground pin. A tic tracer will not find this problem unless something with a large enough metal surface which is connected to the ground pin of a 3-wire cord is plugged into the miswired receptacle.

Edit: Typing while Mike posted
 

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I also found a RPBG outlet in a church just last year where I was teaching a sound mixing seminar with 20 mixing boards on the desks for students, all of which were plugged into a "new" outlet on the wall.
Hey....ever hear of the "Light Viper" audio over fiber optics? We have sold a number of systems to churches around the U.S. and also have an optic card that plugs into Yamaha consoles.
 

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No...what he is saying is if the neutral and hot are switched on a receptacle and then someone bootlegs the ground (to the hot now) you will have 120 volts on the on the ground pin. A tic tracer will not find this problem unless something with a large enough metal surface which is connected to the ground pin of a 3-wire cord is plugged into the miswired receptacle.

Edit: Typing while Mike posted
Actually, a tic tracer WILL find the "hot" ground in an RPBG receptacle by itslef, but only when you get close to the front of the outlet, perhaps an inch away. But a tic tracer will light up from several inches to a foot away from a large energized surface caused by a RPBG or any other hot ground problems.

See the picture below. And please wire one up for yourself and try it.

Mike Sokol

 

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Mike, what is red/green designation there?

~CS~
In the picture above, Green indicates the NCVT is turned on without sensing any voltage, while Red/beeping means it's sensing at least 40 volts AC. This is a standard 90-1000 volts NCVT. The low-voltage versions designed for 24-volt control circuit tracing are too sensitive to use around 120-volt outlets, since they can't tell the difference between a normal hot and neutral outlet contact. The tester in the picture is a Klein NCVT-1. Klein also makes a NCVT-2 version with both high and low voltage settings, using a green light for on, red light for high voltage (over 40 volts) and blue light for low voltage (under 40 volts), but it's a bit too complicated for most outlet testing, I think.

I have NCVT's from half a dozen manufacturers and try them on all types of wiring situations. Right now the Fluke, Amprobe, and Klein products are my favorite testers in terms of ruggedness and reliability. But your mileage may vary...

Mike Sokol
 
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