Remarkable electric shock I experienced

[R Blankenship]

I experienced an electrical shock while replacing an A/C Fan Coil's 120vac, single phase motor that was above the ceiling grid in an office, while I stood on a fiberglass ladder and having no other voltage, neutral, nor ground point in the electrical shock -It was severe enough to lock me to it and leave blisters on entry and exit points. Here are the details: I was time constrained and in a hurry; and convinced of the concept of the "bird on a high tension wire" not getting shocked, and not troubling with turning off the breaker NOT putting on gloves, I began to strip the Stranded (THHN) "live" wire feed to make the necessary connection to the motor lead, using a wire stripper designed to strip solid copper insulated wire -this requires a little extra "umph" to pull the insulation off the stranded copper wire; so holding the Wire Stripper in my right hand (index Finger touching its metal, uninsulated portion of the Wire Stripper) and my left hand holding the "live" (120vac) wire by its insulated covering, I used my left Thumb against the Wire Stripper for the "umph" to pull the insulation away; at which point I compressed the Stripper to cut the insulation and pressed my thumb against the Wire Stripper to pull the wire apart from the end of the now stripped insulation; at which moment, I became hung to an electric current traveling through my Hands, Arms and Chest. I thought of walking down the ladder, to free myself; but thought I might NOT be able to break loose; so I slung my legs out side ways to cause the ladder to tip out and I fell to the floor, landing unconscious but freed of the shock! It taught me that a single voltage can cause death by electrical shock and the "bird on the wire" is a "false flag" concept.... My thought (as to how that was possible) is that the left Thumb and right index (less than an inch apart on the wire stripper) set up a capacitor circuit and my arms and chest became the dielectric!?!

 

[R Blankenship]

You have been incredibly lucky not to do any more damage....
In fact, you should mention this to a doctor, just in case.

Your analogy of a bird sitting on a wire is flawed.... The cables up there are possibly insulated... not by much, but there will need to be some... just to stop the cables corroding more than anything else.

Ive never actually tested how resistive a fibreglass ladder is..... but unless its marked as being safe f0r live work.... (like insulated screwdrivers) i would't trust it.

Littlespark, imagine how much weight is added to insulate transmission lines, if this were the standard. Or imagine the usefulness of an insulated electric cattleguard fence that a Rancher uses to discouraged their Cattle from traveling any further and upon which a bird safely perches itself without a shock.... Now,xI failed to mentionbthat on this service-Call, I had trouble-shot, found the motor had failed, cut the feed's "hot"/"live" wire and put a wire nut on its exposed end and set it aside to remove and replace the motor.... -I cut the wire with the same wire-Stripper with my right hand while holding the "live" wire's insulated wire with my left hand..., all without receiving a shock or henerating a spark on that "live" wire in which no current presently traveled.
I can assure that I am NOT the first NOR will I be the last to proceed along this path -That is partly why I posted this remarkable conditions for a shock.

 

[R Blankenship]

I would hope any senior electrical worker wouldn't be stupid enough to work on live wires.

Here, Westward10, is a little more background on that service Call: I trouble-shot the Fan-Coil and found the motor had failed. I then cut the feed's 120vac "live" wire with my wire-Stipper (holding the insulated wire with my left hand) and placed a wire nut on its now exposed tip and set it aside (no shock then, even though I used my hands without gloves or turning the Breaker off), while I replaced the motor. Once replaced, I then needed to remove 11/16" of the feed-Wire's outer -end insulation to "mate" it to the new motor's lead wire. It was then, after crimping and begin leveraging that 11/16" of insulation.off when, I guess, the movement caused the now exposed "live" wire to touch the wire-Stripper's exposed metal and set up a current that traveled back and forth through my left Thumb, hand and arm, chest, heart, right arm hand and index finger... -there was no other circuit components and NO other delta-V other than generated from Harmonics or other dirty signals on that wire.... My guess is that these Harmonics and variants generate a current and yhat this is what cause "heating" on the wire even when the circuit has NO demand from the end-User.

 

[R Blankenship]

I have never seen a bird stood on a step ladder, put a hand or any other part of their body on a live wire.

James, let me assist you, high tension transmission lines would be formidable to transmit long distance if weighted with insulation. But, check out a Rancher's electric fence with its high-tension, uninsulated wire that discourages the Rancher's Cattle from traveling past that point... -waolit and watch a bird safelyvperch itself on that high tension wire -or if in a hurry, go up to it and touch it with your hand while jumping into the air and experience for yourself how you only feel a shock when you land back on the ground while still touching that Rancher's electric Cattle guard fence.

 

[DPG]

James, let me assist you, high tension transmission lines would be formidable to transmit long distance if weighted with insulation. But, check out a Rancher's electric fence with its high-tension, uninsulated wire that discourages the Rancher's Cattle from traveling past that point... -waolit and watch a bird safelyvperch itself on that high tension wire -or if in a hurry, go up to it and touch it with your hand while jumping into the air and experience for yourself how you only feel a shock when you land back on the ground while still touching that Rancher's electric Cattle guard fence.

I think we all know the theory behind this to be honest, it's fairly basic and fundamental.

What you experienced was a completed circuit, however it was formed. Nothing to do with harmonics. And I'm not sure where you are going with your 'delta V' comments.

 

[R Blankenship]

I think we all know the theory behind this to be honest, it's fairly basic and fundamental.

What you experienced was a completed circuit, however it was formed. Nothing to do with harmonics. And I'm not sure where you are going with your 'delta V' comments.

"Delta" is engineering terminology for "difference" -whether 120vac and ground or whatever has a voltage difference in which current can potentially flow -in my circumstance the "delta V" existed on a single 120vac wire.... My guess is that "harmonics" on wires (seen often in commercial electrical wiring systems) generates heat due to the delta V of Harmonics in which multiple frequencies exist and so current will flow in a single "live" wire... -a concept my training never touched upon but nearly ended my life....

So more background on that troubleshooting and replacing a failed motor: Once determined the motor was bad, I cut the feed's "hot"/"live" wire with the same wire-Stripper and bare hands, then wire-nutted its exposed end and set it aside as I replaced the motor... all without being shocked, and my left hand only touching the "live" wire's insulation.

 

[timhoward]

I was time constrained and in a hurry; and convinced of the concept of the "bird on a high tension wire" not getting shocked, and not troubling with turning off the breaker NOT putting on gloves

Have you actually read back what you wrote?
There’s enough in those few words for an employer to send you on a week long training course.

Why would you ever bank on any solid object completely isolating you from earth, and rely on that as a means of safety?

In my career I’ve once realised that I should be getting a shock and wasn’t. I’d turned the wrong thing off and stupidly didn’t check. It was a very hot day, a very dry concrete floor and a wooden ladder (which dates it!) saved me. My learning point was certainly NOT that in these circumstances I don’t need to bother isolating in future.

You can write as much as you want but nothing will change the fact that it was a foolish gambit in the first place.

 

[DPG]

"Delta" is engineering terminology for "difference" -whether 120vac and ground or whatever has a voltage difference in which current can potentially flow -in my circumstance the "delta V" existed on a single 120vac wire.... My guess is that "harmonics" on wires (seen often in commercial electrical wiring systems) generates heat due to the delta V of Harmonics in which multiple frequencies exist and so current will flow in a single "live" wire... -a concept my training never touched upon but nearly ended my life....

So more background on that troubleshooting and replacing a failed motor: Once determined the motor was bad, I cut the feed's "hot"/"live" wire with the same wire-Stripper and bare hands, then wire-nutted its exposed end and set it aside as I replaced the motor... all without being shocked, and my left hand only touching the "live" wire's insulation.

I know what delta means! I was referring to your theory involving that and harmonics.

A completed circuit was formed which incorporated you. I don't know how because I wasn't there. But current flow needs a circuit. You have not discovered some new aspect of electricity here.

 

[littlespark]

Different animals (and different individuals of the same animal) take electricity different ways…

Electric fences, although just a nuisance to cattle, can give some humans a good crack, but others don’t feel it at all. ( high voltage, no current)

A momentary brush against mains voltage (230 in UK) can give a human a short lived “tingle”…. The same tingle can kill a horse.


Maybe birds don’t feel electricity the same? I haven’t tested any.

I know squirrels don’t like 400v up their tail️

 

[timhoward]

You have not discovered some new aspect of electricity here.

If he had, then by his own reasoning there would be a heck of a lot of dead birds, and things like this would not be possible:

 

[westward10]

Electric fences work on the principle of limitation of discharge of energy, this used to be on the old Periodic Inspection Reports.

 

[plugsandsparks]

I don't think there is any mystery here. I guess most if not all have experienced a shock when are best laid plans of working safely fail. I have experienced one, similar to the OP in that , in theory, there was not supposed to be a route to earth. It was just a momentary brush against a live wire but the actually emotional "shock" made me pull back so hard and fast that i banged my elbow and that really hurt for days.

I had never thought of trying to work out why at that point i had created a circuit when in theory it should not have happened as i have enough knowledge to know that there is no such thing as infinite resistance on the planet, it always has a value, clearly the value at that time was enough to enable a small current to flow.

In the ops case i don't believe harmonics on an open cct will make any difference as the human body is mainly resistive, it is more likely he had a route to complete the cct he was unaware of, perhaps through earth or maybe he was leaning on the a/c unit, who knows ?

 

[R Blankenship]

I know what delta means! I was referring to your theory involving that and harmonics.

A completed circuit was formed which incorporated you. I don't know how because I wasn't there. But current flow needs a circuit. You have not discovered some new aspect of electricity here.

Harmonics and "dirty"/variant voltages are induced back into a wire from end-use equipment such as computers or can get impressed into the wire from nearby circuit flow, etc. These voltage differentials set up current flow that causes the wire to be heated up beyond what is expected by the circuit"s end-use loads...; and apparently-
(from the phenomenon I experienced with left Thumb and right index Finger resting on the wire-Stripper's metal touching a single 120vac live wire, less than an inch apart) is enough with these delta-Vs to cause a current to flow from Thumb and Index Finger and all parts in between (re.: Left hand, arm, chest, heart, right arm and hand) strong enough to lock up associated muscles and cause me to either force a fall from, walk down (and hope I can break the circuit) the Ladder to breaks its deadly grip or suffer electrocution.

 

[R Blankenship]

Have you actually read back what you wrote?
There’s enough in those few words for an employer to send you on a week long training course.

Why would you ever bank on any solid object completely isolating you from earth, and rely on that as a means of safety?

In my career I’ve once realised that I should be getting a shock and wasn’t. I’d turned the wrong thing off and stupidly didn’t check. It was a very hot day, a very dry concrete floor and a wooden ladder (which dates it!) saved me. My learning point was certainly NOT that in these circumstances I don’t need to bother isolating in future.

You can write as much as you want but nothing will change the fact that it was a foolish gambit in the first place.

The "circuit" I was in had NO ground potential -the circuit was as single 120vac "live" wire, the wire-Strippers metal touching the "live" wire, my left Thumb, hand, arm, chest, heart, right arm, hand, and index Finger (which was approximately an inch away from the left thumb both contacting on the wire-Stripper); all of which could feel the current FLOW, and associated muscles that were in turned locked/held fast to. The circuit was broken when I swung my legs sideways to topple the Ladder and induce my fall and break the current that flowed through and blistered both entry and exit points (re.: left Thumb and right index finger).

 

[timhoward]

The "circuit" I was in had NO ground potential

The circuit was broken when I swung my legs sideways to topple the Ladder

So the shock stopped when the current path to ground was interrupted.
If you can't see that the ladder was simply not the insulator you were hoping for / banking on, then I've nothing more to add.
I'd hoped to convince you that working like this isn't safe. It seems I'm not able to do that.

 

[westward10]

Several posts now removed, no more side tracking please.