Proximity current detector

[rick carpenter]

I'm looking for a simple, bullet-proof, and cheap proximity current detector that would not take more than five minutes to learn and could be stored in a disaster equipment trailer that might be unused for months at a time. It doesn't have to have any more features than place it close to the wire in question and tell me if the power is on or off. Any recommendations?

I was part of a team that did some tornado relief work last weekend in Rowlett TX. At the house in the pic and in countless others elsewhere, plenty of NM cable, main feed cable, etc is exposed and needs to be cut to remove material. In this case, they told us the power was off so therefore no problem cutting cables when we needed to. It is not enough just to trust what should be obvious and what we were told, I want to be able to see with my own eyes that it is true especially being a team leader and responsible for others. Here we knew the power was off because we saw that the main feed had been cut.

 

[wyliesdiesels]

I use these. Inductive voltage tester.

http://www.amazon.com/dp/B000EJ332O/?tag=atomicindus08-20

 

[kursplat]

probably going to get someone to disagree with this, but there is NO "proximity current detector" that is 100%.
we call them tic tracers at work.
my personal opinion: anything other than a meter that's been tested on a hot source, just before you use it on the "supposedly" de-energized equipment, is not 100%. and that isn't 100% unless you can see all the opens and it's shorted and grounded.
rarely do you get 100%

thanks for the relief work you do, stay safe

 

[theoldwizard1]

There are dozens of "non-contacting" voltage detectors out there. Buy a brand name. (Wylie linked a good one.) Buy extras. Buy extra batteries Do NOT store them with the batteries installed if they are going to sit for months. I would put the batteries in a small ziplock bag and then put that bag in another ziplock with the tester.

I don't think they will work through metal conduit or flexible armor like BX.


(Picking a nit: You can't have "current" until you have a completed path from a higher voltage to a lower voltage (ground). You are detecting the presence of a higher voltage.)

 

[jdieter]

I'm assuming your talking about residential wiring so beyond a reliable method of testing, if the main entrance panel is still intact you could ground the feeders. A set of battery jumper cables from each hot wire lug to the ground rod or neutral wire would work fine.

 

[wyliesdiesels]

I'm assuming your talking about residential wiring so beyond a reliable method of testing, if the main entrance panel is still intact you could ground the feeders. A set of battery jumper cables from each hot wire lug to the ground rod or neutral wire would work fine.

As long as the ground rod is bonded to the neutral bar that should work. Otherwise, need to go from hot to neutral.

 

[Zeke]

I'm assuming your talking about residential wiring so beyond a reliable method of testing, if the main entrance panel is still intact you could ground the feeders. A set of battery jumper cables from each hot wire lug to the ground rod or neutral wire would work fine.

As long as the ground rod is bonded to the neutral bar that should work. Otherwise, need to go from hot to neutral.

I don't think I'd like to be the one that hooks that arrangement up.

BTW, what would happen if an abrasive wheel were used to quickly cut through a hot SEC? The kind you see with a gas engine.

 

[Norcal]

I would call any of those testers" bulletproof" nor would I rely on them 100% either but still is not a bad idea.

 

[wyliesdiesels]

I don't think I'd like to be the one that hooks that arrangement up.

BTW, what would happen if an abrasive wheel were used to quickly cut through a hot SEC? The kind you see with a gas engine.

U would still get nasty sparks and flash.

Depending on the size of feeding transformer, the line cutouts may or may not pop.

 

[bczygan]

$11 @ HD:

http://www.homedepot.com/p/Commercial-Electric-Non-Contact-AC-Voltage-Detector-MS8907/205620398?keyword=ms8907

 

[Norcal]

$11 @ HD:

http://www.homedepot.com/p/Commercial-Electric-Non-Contact-AC-Voltage-Detector-MS8907/205620398?keyword=ms8907

Commercial Electric?????? Stay away.

 

[Mongo68]

We use these at work...
http://www.techtoolsupply.com/Telco-FVD-Foreign-Voltage-Detector-Pouch-p/tel-fvd.htm

 

[wyliesdiesels]

Damn those are pricey!

 

[ssdave]

Having used several, I like the Fluke best. Have worked the longest, and been the most reliable.

 

[firworks]

Real Tool Reviews just did a video on one:

 

[jdieter]

I don't think I'd like to be the one that hooks that arrangement up.

BTW, what would happen if an abrasive wheel were used to quickly cut through a hot SEC? The kind you see with a gas engine.

My assumption was the main entrance panel is dead as verified by a reliable tester. Grounding feeders after a verifying a de-energized circuit is standard practice in high voltage work.

 

[rlitman]

probably going to get someone to disagree with this, but there is NO "proximity current detector" that is 100%.
we call them tic tracers at work.
my personal opinion: anything other than a meter that's been tested on a hot source, just before you use it on the "supposedly" de-energized equipment, is not 100%. and that isn't 100% unless you can see all the opens and it's shorted and grounded.
rarely do you get 100%

thanks for the relief work you do, stay safe

I completely agree with you. Non-contact voltage detection is in no way 100% accurate, and I would in no way count on it in life-safety situations.

Real Tool Reviews just did a video on one:

I've got one of these, and the newer NCVT-2. I'd call them minimally acceptable.
Unacceptable, would be the myriad of non-contact testers that do not indicate their operational status, and have just one light for voltage detection.
The Klein models light up green, and change to red when detecting.
Even so, I wouldn't trust it at all unless I confirm it is able to detect a live voltage immediately before EACH use.

If you want to SEE that a circuit is not live, there are better ways, such as seeing that it is bonded to earth. Even testing with a real meter doesn't guarantee safety, as without the ground connection (or if you're within eyesight of a disconnect), how can you be sure the power will not be turned back on?

 

[Old Engineer]

I'm looking for a simple, bullet-proof, and cheap proximity current detector that would not take more than five minutes to learn and could be stored in a disaster equipment trailer that might be unused for months at a time. It doesn't have to have any more features than place it close to the wire in question and tell me if the power is on or off. Any recommendations?

I was part of a team that did some tornado relief work last weekend in Rowlett TX. At the house in the pic and in countless others elsewhere, plenty of NM cable, main feed cable, etc is exposed and needs to be cut to remove material.

I support that no NCVT is 100%. Especially in the example you give above. If you had NM exposed to the elements (tornado causing debris in rain), that wet NM could prevent the unit from detecting. This is shown in the video below.

With that said, I would suggest the Klein NCVT-3. It is not a simple On/Off detection with a single LED. It has 5 LED's which tell you how close to power you are. It also has a built-in Flashlight that could really help is a disaster situation, and add in the fact it is waterproof if there are still storms during the disaster. Also has a battery level indication. Best tester for the situation you described.

 

[simpler=better]

Whatever you buy, feed it energizer disposable lithium batteries. They don't leak, work in the cold, and have a 10+yr shelf life. Well worth the $2/battery for a case like this.