Electrical

Archive Public Archive
1

Originally Posted By: ekartal
This post was automatically imported from our archived forum.


Another newbie question… If a hot wire is touching the inside of a panel box isn’t that potentially lethal even if just touching with the back of the hand? If answer is yes, why do we do it? I know it’s a major part of the inspection but hey we don’t think twice about not climbing second story roofs…


Thanks Erol

2

Originally Posted By: mbailey
This post was automatically imported from our archived forum.


Erol,


I have always considered the ?back of the hand test? downright ignorant ? you have no idea what is in that panel or what has been done in that panel - that is why voltage testers, tic tracers etc? are made

I personally do not like to use my body as an electrical test instrument?

--
Mark Bailey
Stonegate Property Inspections LLC
Ponca, NE

3

Originally Posted By: gbeaumont
This post was automatically imported from our archived forum.


Hi Erol


yes a live touching the panel could kill you under the right circumstances.
you should touch the back of your hand against it first, as if it is live the natural reactions of your arm muscles will tend to throw your hand off the panel.

Despite the inherent potential dangers you must remove the panel cover so you can check for all manner of other issues like, aluminum brach wiring, illegal taps, burnt wires etc, at least with a roof you can see whats going on without climbing on to it, you cannot do the same with a panel

Regards

Gerry

--
Gerry Beaumont
NACHI Education Committee
e-mail : education@nachi.org
NACHI phone 484-429-5466

Inspection Depot Education
gbeaumont@inspectiondepot.com

"Education is a journey, not a destination"

4

Originally Posted By: ekartal
This post was automatically imported from our archived forum.


Thanks guys for your feedback. How about some more…


As everyone would agree, you can’t inspect what you do not see. I do not like the idea of touching a panel to see if I am going to get shocked or not.


I know there are hazards as part of this job, but I am now thinking about investing in a non-contact voltage tester for piece of mind if they will detect live wire in a panel box. Do they work? I already know they’re expensive…


Thanks Erol

5

Originally Posted By: cradan
This post was automatically imported from our archived forum.


. A much better way to avoid “becoming one” with the structure’s electrical system.[/url]

–
Chris


http://www.inspect4me.com


Chicago Illinois Home Inspections

6

Originally Posted By: gbeaumont
This post was automatically imported from our archived forum.


panel door it was as I was lifting the cover off, slipped and connected it to the SEC, now that woke me up icon_eek.gif


Regards

Gerry

--
Gerry Beaumont
NACHI Education Committee
e-mail : education@nachi.org
NACHI phone 484-429-5466

Inspection Depot Education
gbeaumont@inspectiondepot.com

"Education is a journey, not a destination"

7

Originally Posted By: jmyers
This post was automatically imported from our archived forum.


I know that I am not the smartest inspector out there but I always pull the cover off with two hands, tilting the bottom of the cover off toward me first, then lifting slightly upwards and then straight back toward my face. I figure I can live without a few fingers but that eyesight would certainly make me wanna die.


BTW...I do wear glasses. If you don't get some goggles. ![icon_biggrin.gif](upload://iKNGSw3qcRIEmXySa8gItY6Gczg.gif)

Joe Myers

8

Originally Posted By: Dennis Bozek
This post was automatically imported from our archived forum.


Again I refer to the “hot chassis” check. Promptly lick your index and middle finger and place against the panel. If you get a tingle, there could be a problem. If your hair curls, there is a problem! If you die…you deserve it cuza you listened to me icon_lol.gif


A voltage tic tracer will read a neutral wire as a hot in knob and tube wiring.....tis true. Most testers are more sensitive than others and a unterminated neutral can cause the thing to go off!!

If there is a hot wire touching the panel and it does not trip some breaker somewhere....the panel has no ground or bond from the neutral to the enclosure. Therefore panel is live and as long as you do not ground yourself....as you remove the cover....your hair will not curl. It is possible to grab the end of a stripped hot wire and hold it if you do not ground yourself. As soon as you do tho....chances are because house voltage is a alternating voltage.....it will kick you off in most cases....believe me I know....my hair is not naturally curly!!

--
This information has been edited and reviewed for errors by your favorite resident sparky.

9

Originally Posted By: mbailey
This post was automatically imported from our archived forum.


Dennis,


What the hell kind of answer was that. That has got to be the most irresponsible bunch of BS I have heard. Erol is a new HI learning the business, asking a legitimate question - and you are telling him that.

You proclaim your years of experience as an electrician on this board?what happened to maturity. This is message board ? no one can hear you chuckling as you write that crap. Not everyone can tell what is a joke and what is not!

Case in point might be Erol?s family after he gets fried because of some BS advice an experienced electrician gave him in answer to his question ? think about it!

--
Mark Bailey
Stonegate Property Inspections LLC
Ponca, NE

10

Originally Posted By: jmcginnis
This post was automatically imported from our archived forum.


Just a small but important bit of advice for Erol and the rest who are interested… even if you decide to use a meter of some kind to see if a panel or anything else for that matter is energized… the first thing you want to do is CHECK THE METER… a bad meter will give no indication and could lead you to believe that the circuit is dead when actually the meter is bad … so try the meter on a circuit that you know to be live first… and after you are sure the meter is operating then test the circuit that you will be handling…by the way… I always check with a meter and after the meter says it’s safe, then I use the back of the hand method rather than grab anything because of the very problem that Gerry mentioned about muscle contraction and getting frozen on the circuit… one more thing, 120 volts is 3 to 4 times the voltage necessary for a fatality and 1/10 amp (100 miliamperes) is all the current it takes to kill you … be careful!!!1

11

Originally Posted By: Dennis Bozek
This post was automatically imported from our archived forum.


I did put a laughing smiley on the end there Mark…sheesh. I also answered the question in that I stated certain things about tic tracers that some may not know…sheesh. The last statement is true as well, in that if you do not ground yourself…you wont feel any voltage or current traveling through your body…sheesh. So the point is…when removing a cover from a panel…don’t ground yourself…and pull it straight off…not at an angle which would give you a chance to dip the cover into the main lugs of the panel…sheesh…do all of those things and yes you wont curl your hair!! Maybe you are bald and just jealous of my unnaturally curly hair!

–
This information has been edited and reviewed for errors by your favorite resident sparky.

12

Originally Posted By: rmeyers
This post was automatically imported from our archived forum.


Erol,


On several occasions I have observed SEC or circuit wires laying against the front side of the panel box with the insulation damaged by the panel cover screws. (Homeowner replacement screws are often too long and pointed, a bad combination) Make sure the wires are pushed back far enough that reinstalling the panel cover screws doesn't penetrate the insulation of adjacent wires and cause a short or energize the panel cover.

This is another reason to carry an assortment of extra panel screws with you as recommended in a previous "tips" thread.

Be Careful & Good Luck!!!!!

--
Russ Meyers

13

Originally Posted By: Dennis Bozek
This post was automatically imported from our archived forum.


I hate to do this guys but I just have to say…the main panel must be grounded and the sub panel must be bonded back to the main panel equipment ground. If that panel is hot due to a wire touching it…something is wrong. If there is a hot wire laying against that panel, that breaker for that wire had best be tripped…if it is not…that panel is not grounded. If you encounter a panel that has it’s metal enclosure energized by a wire that is either touching it or has a tear in it’s insulation allowing it to touch the panel…I would recommend that a qualified electrician be contacted to properly ground the panel. If you are inexperienced with the handling of “live” electric, I suggest you leave it to the professionals. If you must remove the panel cover, use either rubber or leather gloves and thick rubber soled shoes so that you do not ground yourself in any way as you remove the cover. If you see a wire shorting out against the enclosure, you can use something insulated against electrical current, such as wood, rubber, even cardboard, to move the wire away from the metal. Find the breaker for the wire and turn it off. This will allow you to move the wire safely, if you want to play electrician. Either way…if the panel is properly grounded, the breaker for the wire that is touching the enclosure should trip…that is unless it is a FPE panel…in that case it may look like the 4th of July upon the removal of the panel cover!!!

–
This information has been edited and reviewed for errors by your favorite resident sparky.

14

Originally Posted By: ekartal
This post was automatically imported from our archived forum.


I plan on investing in a good non-contact voltage detector. If it detects a problem inside the panel I will not open it. I don’t care if that costs me business.


Erol

15

Originally Posted By: Dennis Bozek
This post was automatically imported from our archived forum.


Better safe than sorry Erol…sorry about my previous post…I was just having some fun…I am a sparky in case you didn’t know. Just be careful of the “tic” tracers. They often give false readings. They should first be used on a actual live circuit to determine fuctionability of the device before testing what you might think to be “live”. Another way to determine if a panel is hot is with a voltmeter. Touch the panel with one lead and a water pipe with the other. If you read voltage there is a good chance the metal on the panel is energized. Of course this only works well if the panel is grounded. You might have to scratch the paint to make good contact with the panel surface or better yet, just touch the panel screw.

–
This information has been edited and reviewed for errors by your favorite resident sparky.

16

Originally Posted By: roconnor
This post was automatically imported from our archived forum.


Forget the “back of the hand” thing … leave that up to licensed sparkies.


A sparky also once told me to first check out everything using a meter/ticker with one hand in your pocket (or at least think that way). Even if it looks okay, still treat everything as if it was hot. And use 3 layers of protection (insulated tools, insulated gloves, insulated boots, dry floor, etc).

A nasty shock from the panel can kill you! ... ![icon_eek.gif](upload://yuxgmvDDEGIQPAyP9sRnK0D0CCY.gif)

--
Robert O'Connor, PE
Eagle Engineering ?
Eagle Eye Inspections ?
NACHI Education Committee

I am absolutely amazed sometimes by how much thought goes into doing things wrong

17

Originally Posted By: ekartal
This post was automatically imported from our archived forum.


Robert,


Is a good non-contact voltage detector sufficient enough to detect a hot box panel?


Thanks Erol

18

Originally Posted By: jfarsetta
This post was automatically imported from our archived forum.


The theory behind the one hand rule when initially touching a panel is to touch it with the back of your right hand. The back of the hand means that your muscles are less likely to grab and cause you to hold on to the energized metal, and the right hand is the furthest hand (electrically) from the human heart.


I use a tic tracer. I test it at the start of the inspection. If the panel looks like Harry the Homeowner has had a piece of it, I'm extra careful.

19

Originally Posted By: jmyers
This post was automatically imported from our archived forum.


Joe F.


How can you tell that Harry the homeowner got there first, without opening up the panel?

Joe Myers

20

Originally Posted By: Dennis Bozek
This post was automatically imported from our archived forum.


The only way you will get a zing off of a live electrical panel enclosure is if you somehow provide a path for the voltage to go…or in other words you ground yourself in some way. Now as crazy at it may sound and as absurd as some of you might want to tell me about, it is possible to hold on to a single line of ac voltage without getting shocked…if you DO NOT ground yourself. There is no place for the voltage to go…therefore current cannot be produced using your body as a resistor…nor can you get shocked.


Now dipping the cover and hitting the main lugs of the panel will not shock you but it will scare the bajeebies out of ya as I am certain Jerry found out. By doing that you cause the phase A line to be shorted to the phase B line and you make a nice fireworks display that will definitely scare you half to death. The voltage does nothing to you but the current can kill. Do not complete a path for the voltage to go....and you have no current. If you suspect a panel to be live, where protective glove and a good pair of insulated boots.

A tic tracer may or may not be the way to go in determining a live panel. My suggestion would be to take a multimeter set on voltage. Touch one lead to the panel and the other lead to some sort of ground, like a water pipe or even your finger. If there is any potential on the panel the meter will read it. If so, take the proper precautions and remove the panel cover, being very sure you do not ground yourself, giving that voltage a place to go. When touching the panel with the voltmeter lead, touch it someplace that is not painted, such as the panel cover screw. If you touch it in a area that is painted, you might not read a thing because of the paint.

Once you determine the metal parts of the panel are not HOT, remove the panel cover by pulling it straight back. Dipping it or tilting it is dangerous for it can be dipped or tilted into the main lugs of the panel thus causing you and the panel to go BOOM. Moving the cover left or right as you pull it off can also open up breakers and if there are people in the house, perhaps on the computer, you can shut them down before they have a chance to save anything....that is a sure fire way to piss off a client.

Although they are not insulated against electrical shock, I as a sparky wear leather gloves. I work on live services and reconnect the loop wires to the service wires while wearing leather gloves. You can buy a reasonably priced pair of leather gloves from Walmart or Sears for about $10. Wear these gloves when removing the panel cover. They will help insulate you against any potential shock hazard. If you want to get extreme, for about $500 you can buy a pair of HOT gloves which are rubber insulated and protected to 20,000 volts. They have a rubber glove insert and then a outer glove which is typically leather or cowhide. They are quite bulky and very difficult to work in.

In regards to a recent response to me....I am not out to fry you guys. Lookie here...I've been doing sparky stuff forever....I touch live electrical lines every day.....and as long as I do not ground myself and allow a path for voltage to go....I will not get shocked. I am not telling you to try it or even asking you to, I am just stating the facts. Do not ground yourself and you won't get zapped. If you are holding on to some sort of conductive material when you put the back of your hand to the panel...WHAM.....you have just grounded yourself!! Stand away from the panel and secure the hand that you are not using by placing it in your pocket or behind your back and then touch the panel. However, you still would not know the panel is live for the voltage that might be present there is now in your body, but because it has no place to go..no path to follow....you feel nothing. The best and most efficeint way to determine if a panel is hot....is to measure it...to a grounded source, such as a water pipe. If you have to add 10 feet of wire to one lead to get back to a ground....do it. Touch one lead to ground the other lead to the panel cover screw and if you read zero....there is no voltage on that enclosure to make your hair curly.

--
This information has been edited and reviewed for errors by your favorite resident sparky.