Two prong tester!

[zbang]

Reuben-

The common NE2 neon lamp has a design current of between 0.3 and 0.7ma, since the lamp has a negative resistance coefficient (resistance goes down when current goes up) this is usually regulated by a resistor (maybe 80-150k). If either the resistor's value changes downward or it shorts, you loose that regulation and current can shoot up to over 5ma. That's a dangerous level for a human. If the neon lamp shorts, you're at the mercy of the single resistor. If both short, you're just grabbing the hot lead. There is no other protection. When you're gripping the device as shown, your fingers can readily lock onto it.

Considering this a safe device is akin to testing voltage with a dry finger- you can do it; many have and survived; but as they say, failure only needs to happen once.

I think what's bothered people most is hacking up a fairly safe device to fill a need that is already filled by a quality commercial device. Now, I know, hot sticks cost more than outlet testers, but really, is your life worth more than $20? I'd think it is, so why get the right tool for the job? (Or, another way, would you put your extension ladder up on milk crates to make it reach a roof? Might work most of the time, but when it doesn't, it's a big problem. Use a taller ladder and it's not a problem.)

 

[charlie b]

Let me take things in their proper order. First of all, I owe you an apology.

This comes from your forum rules: ?You agree, through your use of this service, that you will not use this forum to post any material which is knowingly false and/or defamatory??

Thank you for that reminder. You are quite right to feel that we did you a disservice. Specifically, despite the fact that you were not, at the time, a member of this forum, I should have taken notice of the insulting nature of these two comments, and removed them:

?Just look at his picture on the right side of the blog. He looks like he has had more than just a tingle using his contraption while standing on wet concrete.?

and

?The guys an idiot?

I apologize for being remiss in my moderator?s duties, and for not immediately deleting those two comments.

This comment, however, I stand by, and will reiterate as many times as I believe to be necessary.

?extraordinarily stupid idea.?

I can freely declare an idea to be stupid, without including any reflection on the person who came up with that idea. Smart people sometimes do stupid things. I have no notion of how smart you may be, but the idea of intentionally taking a shock, however slight, is an extraordinarily stupid one. There, I said it again, and I offer no apology for having done so.

Aside from that, I removed the post at ActiveRain because of all the nasty comments. I asked the first commenter to prove how this was unsafe. I expected someone to give a logical explanation of how this device could cause someone to get injured, but all I got back was several more insulting comments from people telling me their professional background.

I was glad to see the post removed. And if you were talking about my failure to give a logical explanation of the danger, I thought my second post on that forum was an explanation. I didn?t keep a copy of my post, and you removed the thread, so I can?t duplicate my earlier comments. Here is a quick summary of the issue.
? Anytime your hand feels a shock, some amount of current is also flowing through your body, including through your heart. I don?t think I need to prove that to you, because you said that you understood the notion that current takes all available paths back to its source. If you want more of an explanation on this point, let me know.
? You are relying on the internal resistance of your testing device to limit the current through your hands to a small, non-harmful value. But all things made by human hands will someday fail. If your tester experiences an internal failure, it may no longer be able to limit the current flowing through your body. Thus, you are placing your life at risk, expecting an inexpensive and fragile device to keep you safe.
? If you are willing to post a statement warning others not to try your invention, including the warning that it might electrocute them, and if you are willing to continue to use the invention yourself, then you will need to explain to my why that is not a stupid idea.

 

[Cold Fusion]

---
? You are relying on the internal resistance of your testing device to limit the current through your hands to a small, non-harmful value. But all things made by human hands will someday fail. If your tester experiences an internal failure, it may no longer be able to limit the current flowing through your body. Thus, you are placing your life at risk, expecting an inexpensive and fragile device to keep you safe.
---

http://www.ltl.ca/p10_metering.html

http://www.ltl.ca/pdfs/Potential_Indicators.pdf

Charlie -
I have one of these in 15kV. I use it on circuits up to 13.8kV. It definitely operates by passing a miniscule current through one's body.

Are you saying that this type of device is inherently dangerous?

cf

 

[mxslick]

Apples and oranges

Apples and oranges

http://www.ltl.ca/p10_metering.html

http://www.ltl.ca/pdfs/Potential_Indicators.pdf

Charlie -
I have one of these in 15kV. I use it on circuits up to 13.8kV. It definitely operates by passing a miniscule current through one's body.

Are you saying that this type of device is inherently dangerous?

cf

Your statement makes no sense in the context of what's going on in this thread.

First off, let me quote from your second link:

<snip>The indicator comes with a ground screw on the handle end, and this should be utilized.
Wear insulating rubber gloves and other required safety equipment as per government
requirements or internal policy.

AND

1. The indicator shall always be checked by testing for the presence of voltage on a
known operating voltage. The lamp should glow normally. The purpose of this
test is to ensure the indicator is working. Attach a ground wire to a ground
source when checking for the presence of voltage. Wear appropriate PPE
utilizing proper work method.
i. To connect the unit to ground attached a Ground lead to the ground screw
and the other end to a know ground source.

Note that as a lineman you will be wearing rated gloves for the voltage at hand, and you should, according to the manufacturer's instructions, be using the ground screw provided.

InspectorRubens' device will be and is designed to be used bare-handed.

Second, I am sure the design, testing and quality of that rated hot line tool is much greater than the $20 neon tester used in this case. As was brought up before, what is the CAT rating of this modified $20 neon tester?:roll:

Third, the lineman tool will, ideally, be used ONLY by QUALIFIED and TRAINED persons. The tester in our discussion is open to being used by any one with internet access.

InspectorRuben, welcome to the forum and I am glad you decided to register here to learn more about why we feel is it a very bad idea. Most everyone here is strictly concerned with the safety of everyone who sees your device and for your safety as well. NOTHING anyone says is intended to be a personal attack but you will find a lot of folks here are very passionate in their beliefs and experiences.

And BTW, I have personally had 3 of the same neon testers you modified fail violently in normal use. (2 major burnouts and one where the tester smoked and stopped working.)

 

[Cold Fusion]

Your statement makes no sense in the context of what's going on in this thread. ...

I'm sorry, I couldn't tell that - especially since I read all of the posts and accurately quoted charley b.

I suspect you have never used one of these before - which would explain your comments about the ground wire and the lack of including the difference between checking AC and DC (which has a lot to do with the need for a ground wire).

I didn't say anything about "design, testing and quality", or "QUALIFIED and TRAINED persons" nor am I going to. So I don't have anything to say about the majority of your post

I have no intention of defending the person receiving the arrogant, demeaning bashing. I just have a minor objection to erroneous, all-incompassing statements.

But not to worry, I'll get over it.

cf

 

[mivey]

What's the CAT rating on those?

Cat-II 300v

 

[InspectorReuben]

Responses

Responses

Hi everyone,

Thanks for the replies. I'm new to this forum, so I'm not sure what the standard procedure is for responding to multiple posts... I'll try to make it short and sweet.

So when you are feeling the shock you are receiving at least .5 milliamps of current passing through your body. At 10 milliamps of current you can no longer let go of the conductor.

Chris

Hi Chris, thank you for the professional response.

I wrote "there is so much resistance in my tester that I can?t even feel it. If I?m standing on a concrete floor with wet feet and I try this test, I can feel a very slight tingle."

I certainly wouldn't use this tester barefoot, much less inspect houses barefoot. I included that part to put this in to perspective for anyone reading - my intention was to make it clear that I really am getting a shock. The only time I would use this tester is when I'm in a dry environment and wearing rubber soled shoes, and while not touching metal objects. The tester light is so faint under these conditions that it's just about impossible to see.

How many milliamps of current would you suppose is generated under those conditions? A safe amount?

Reuben-

The common NE2 neon lamp has a design current of between 0.3 and 0.7ma, since the lamp has a negative resistance coefficient (resistance goes down when current goes up) this is usually regulated by a resistor (maybe 80-150k). If either the resistor's value changes downward or it shorts, you loose that regulation and current can shoot up to over 5ma. That's a dangerous level for a human. If the neon lamp shorts, you're at the mercy of the single resistor. If both short, you're just grabbing the hot lead. There is no other protection. When you're gripping the device as shown, your fingers can readily lock onto it.

zbang - that's the most compelling argument I've heard for not doing this test.

On the other hand, what would make my device so different than a voltage probe? Please ignore the fact that my fingers could lock on to my device, whereas this wouldn't happen with the other device.

Reuben-

I think what's bothered people most is hacking up a fairly safe device to fill a need that is already filled by a quality commercial device. Now, I know, hot sticks cost more than outlet testers, but really, is your life worth more than $20? I'd think it is, so why get the right tool for the job?

I own several of those, but they only tell me that there is a live ungrounded conductor present. I still need to pull out a two lead tester to make sure there is also a live neutral at the outlet. Unless I'm missing something, you're suggesting that to test a two prong outlet, I do the following:

- put down my computer
- pull out my two lead tester and use both hands to test the outlet
- put the tester away
- pull out my hot stick (voltage sniffer?)
- verify the polarity is correct
- put the hot stick away
- pick my computer back up again.

Am I missing something?

This comment, however, I stand by, and will reiterate as many times as I believe to be necessary.I can freely declare an idea to be stupid, without including any reflection on the person who came up with that idea. Smart people sometimes do stupid things. I have no notion of how smart you may be, but the idea of intentionally taking a shock, however slight, is an extraordinarily stupid one. There, I said it again, and I offer no apology for having done so.

Fair enough.

You are relying on the internal resistance of your testing device to limit the current through your hands to a small, non-harmful value. But all things made by human hands will someday fail.

We all take risks every day. I imagine the chances of this device failing are pretty slim, and even if it does, I don't intend to be in contact with a grounded surface when that happens.

If your tester experiences an internal failure, it may no longer be able to limit the current flowing through your body. Thus, you are placing your life at risk, expecting an inexpensive and fragile device to keep you safe.

How is this so different than the voltage probe that I included a link to above, other than my obvious design flaw of having the entire tester covered in tape, rather than a very small portion?

And BTW, I have personally had 3 of the same neon testers you modified fail violently in normal use. (2 major burnouts and one where the tester smoked and stopped working.)

No kidding? Did your testers happen to be GFCI testers?

 

[mxslick]

I'm sorry, I couldn't tell that - especially since I read all of the posts and accurately quoted charley b.

Sorry too, and I'm not trying to bust your chops but what you wrote seems to indicate you are questioning Charlies' position. I don't see where he's saying anything about a LISTED, CERTIFIED device made by a manufacturer is inherently dangerous.

I suspect you have never used one of these before - which would explain your comments about the ground wire...

You're right, I haven't used one before BUT I have seen our local POCO
crews use a similar device and it was grounded before use.

...... and the lack of including the difference between checking AC and DC (which has a lot to do with the need for a ground wire).

I re-read the entire instructions provided on that same link and nowhere does it make a distinction vis a vis AC or DC testing, and it repeats the fact that a ground wire should be used. If you see something different (or perhaps the instruction sheet provided with the unit says differently) please post it here.

I didn't say anything about "design, testing and quality", or "QUALIFIED and TRAINED persons" nor am I going to. So I don't have anything to say about the majority of your post

I agree that you did not specifically say anything about "design, testing and quality" , but the idea of both a tested, quality and well-designed device and qualified and trained is part of what's in discussion here. We have someone who may not be qualified or trained building a potentially lethal device and showing it on the internet. You are qualified and trained to work on HV and know the proper proceedures and tools, whereas our subject may not. Surely that is relevant?

I have no intention of defending the person receiving the arrogant, demeaning bashing. I just have a minor objection to erroneous, all-incompassing statements.

I agree and your statement can be construed as erroneous in the context of the discussion here (and the instructions for the tool you linked to) which is why I commented on it.

But not to worry, I'll get over it.

cf

I hope there is nothing you need to get over, as I said it is not/was not my intention to bust your chops, but to point out some things that didn't make sense to me regarding your post, in the context of this thread.

 

[zbang]

On the other hand, what would make my device so different than a voltage probe?

Hard to say, since I don't have one of them. Probably not much. I suspect that the Raffael device isn't rated or tested for use on power line circuits. If it's not, the using the device would be a workplace safety violation. Or, it's no different and shouldn't be used, either.

I own several of those, but they only tell me that there is a live ungrounded conductor present. I still need to pull out a two lead tester to make sure there is also a live neutral at the outlet. Unless I'm missing something, you're suggesting that to test a two prong outlet, I do the following:
[...]
Am I missing something?

Yes, one hand holds the computer (do you put it down to climb a ladder or look under a sink?), the other uses a hot-stick, puts it back in the pocket and grabs another device and plugs that in the socket. For this, you can use the standard outlet tester on a 3-2 prong adapter or you can cut the ground pin off and tape it over. You can also tie a short string between the two to keep them close. (BTW, I don't like the two-wire neon lamp testers either.)

When I've done this sort of thing, I usually put down the clipboard and check all the outlets in the room. If they pass, I don't have anything to write down, so we pick up and move to the next room.

Again, for me part of this is simple quality and trust- I can get a cheap, battered, wooden stepladder at the local flea market or $5 or I can get a new fiberglass one for a lot more. Most of the time, they work just the same, but I trust the fiberglass to not dump me on the ground and to last a lot longer. And, if it breaks, they're someone to go after if necessary.

 

[K8MHZ]

InspectorReuben,

I use a Greenlee GT-11 Voltage Detector and it easily indicates which side of a receptacle is hot.

I guess it leaves the question about the neutral side, though. To me, the best way to check a two prong outlet, time being a consideration, would be to use a common 3 prong tester plugged into a two prong adapter. That would indicate the presence of both conductors. Unplug that and use the GT-11 to verify polarity. I can to that in 5 seconds and neither require two hands to use.

I have used many pen type detectors and the GT-11 is the best I have run across. Once you know how to use them they are very sensitive and seldom false.

You should have a non-contact tester anyway, why not make it one that works.

 

[InspectorReuben]

Tester burnout

Tester burnout

And BTW, I have personally had 3 of the same neon testers you modified fail violently in normal use. (2 major burnouts and one where the tester smoked and stopped working.)

Funny, I just had that happen to me today for the first time with my standard tester. The outlet had a lot of paint on it, and as I pushed my tester in to the outlet, there was a big flash and the circuit breaker tripped.

I cut my tester open to figure out what happened; the ground pin pushed itself back far enough to come in contact with one of the wires.

What a coincidence.

 

[InspectorReuben]

Yes, one hand holds the computer (do you put it down to climb a ladder or look under a sink?), the other uses a hot-stick, puts it back in the pocket and grabs another device and plugs that in the socket. For this, you can use the standard outlet tester on a 3-2 prong adapter or you can cut the ground pin off and tape it over. You can also tie a short string between the two to keep them close. (BTW, I don't like the two-wire neon lamp testers either.)

When I've done this sort of thing, I usually put down the clipboard and check all the outlets in the room. If they pass, I don't have anything to write down, so we pick up and move to the next room.

Yes yes, I know... that's what I already do. I was just being a little dramatic with my explanation to try to make my point: it's inconvenient to do two separate tests to make sure that a two-prong outlet is properly wired.

It would be very nice to have a device that does this in one swoop.

 

[InspectorReuben]

I have used many pen type detectors and the GT-11 is the best I have run across.

Ditto. I've had the same one for about three years now.

I guess it leaves the question about the neutral side, though. To me, the best way to check a two prong outlet, time being a consideration, would be to use a common 3 prong tester plugged into a two prong adapter.

Heck, why not use a night light?

 

[kwired]

Yes yes, I know... that's what I already do. I was just being a little dramatic with my explanation to try to make my point: it's inconvenient to do two separate tests to make sure that a two-prong outlet is properly wired.

It would be very nice to have a device that does this in one swoop.

I see a bigger inconvenience in testing three prong receptacles (especially in a home where you know there were at one time only two prong receptacles).

If you plug in your three wire tester and it says everything is OK and you move on how do you know someone didn't bootleg the ground pin off of the neutral conductor?

I see this as a bigger hazard than reversed polarity in most cases.

 

[mcclary's electrical]

Funny, I just had that happen to me today for the first time with my standard tester. The outlet had a lot of paint on it, and as I pushed my tester in to the outlet, there was a big flash and the circuit breaker tripped.

I cut my tester open to figure out what happened; the ground pin pushed itself back far enough to come in contact with one of the wires.

What a coincidence.

Welcome to the forum, Rueben. Good to have you. Anyone who read all the post knows I am the one that used the term "the guys an idiot". I want to offer my apology to you because as noted, that was unjustified.





ps: this picture is the type of failure we were concerned about. Or either failure of solid state circuitry.Both dangerous on your tool

 

[mivey]

On the other hand, what would make my device so different than a voltage probe? Please ignore the fact that my fingers could lock on to my device, whereas this wouldn't happen with the other device.

Other than the let-go issue (which I did not think about until someone mentioned it), the other device has been tested and listed as an outlet circuit tester.

If you were to go through the proper steps to have your device tested to ensure the design is relatively safe, you would get no complaints from me. Nothing wrong with a new idea, but the approach is the issue. Going about this in the wrong way is dangerous for you and for those that follow you. It is not fair to your family or those that depend on you for you to unnecessarily put your life at risk.

add: And welcome to the forum.

 

[tortuga]

Could you repost a picture of what this 2 prong tester is since it was removed?

We use an older version of the Ideal sure test 60-165 (I think a 60-155) with a custom made 2 prong version of a 61-176 adapter. Basicly we made a Y split cord out of an old computer monitor cord (thats what fits the suretest) one end is a standard two prong cord cap and the green wire goes to a 3 prong cord cap and it simply landed on a grounding pin the other pins are unused. We bring a 25 Foot extension cord and plug it in to a known grounded outlet. Then plug the 3 prong cord cap into the extension cord. It is a fancy way of bringing a green wire around the house or office with you.

It gives you all the readings of the sure test; polarity, voltage drop, impedance etc.

http://www.idealindustries.com/prodDetail.do?prodId=61-165
I can't count how many burning out pump, motor, or lamps issues I have solved by knowing voltage drop.
Anything above 8% is reason to upgrade wire size.
It sure will change your perspective on 14 awg wire for home runs if you get one.
Most newer homes (1970's - now) have end of the run bedroom receptacles with voltage drop around 7% pre 1970's older homes tend to have more #12 around here and better voltage drop.
It runs a timed test in GFCI's older GFCI's trip in 199ms newer ones 19ms. I recently tested an old QO GFCI from the 70's at 21ms.
It also showes real fast if that 1/2" EMT is a good grounding conductor since you see the real impedance of the grounding conductor. (I have never seen one fail)
Cheers

 

[wptski]

Could you repost a picture of what this 2 prong tester is since it was removed?

We use an older version of the Ideal sure test 60-165 (I think a 60-155) with a custom made 2 prong version of a 61-176 adapter. Basicly we made a Y split cord out of an old computer monitor cord (thats what fits the suretest) one end is a standard two prong cord cap and the green wire goes to a 3 prong cord cap and it simply landed on a grounding pin the other pins are unused. We bring a 25 Foot extension cord and plug it in to a known grounded outlet. Then plug the 3 prong cord cap into the extension cord. It is a fancy way of bringing a green wire around the house or office with you.

It gives you all the readings of the sure test; polarity, voltage drop, impedance etc.

http://www.idealindustries.com/prodDetail.do?prodId=61-165
I can't count how many burning out pump, motor, or lamps issues I have solved by knowing voltage drop.
Anything above 8% is reason to upgrade wire size.
It sure will change your perspective on 14 awg wire for home runs if you get one.
Most newer homes (1970's - now) have end of the run bedroom receptacles with voltage drop around 7% pre 1970's older homes tend to have more #12 around here and better voltage drop.
It runs a timed test in GFCI's older GFCI's trip in 199ms newer ones 19ms. I recently tested an old QO GFCI from the 70's at 21ms.
It also showes real fast if that 1/2" EMT is a good grounding conductor since you see the real impedance of the grounding conductor. (I have never seen one fail)
Cheers

I have a 61-165 Suretest but the one bad thing about is that if there's a GFCI on the circuit, the ground impedance test trips it. There are loop impedance testers on the market that don't but they aren't available in the USA. I guess that's because that type of testing isn't required here like it is in some other countries.

 

[mcclary's electrical]

Could you repost a picture of what this 2 prong tester is since it was remove?



Here ya go



http://www.structuretech1.com/blog/2010/08/two-prong-outlet-tester/#comments

 

[InspectorReuben]

Welcome to the forum, Rueben. Good to have you. Anyone who read all the post knows I am the one that used the term "the guys an idiot". I want to offer my apology to you because as noted, that was unjustified.

l

Thank you for that.