shocked by lamp

[norwintd]

i had an interesting occurrence today . I was holding a blow lamp in my hand that i had removed from a fixture. I want to grab it with my other hand and it shocked me. It felt like getting shocked by a car battery and the sting lasted for a minute or so. It made a loud enough snap that the person beside me heard it. I was wondering if this has ever happened to anyone else?
Could a lamp store a charge like a capacitor or was it a static charge amplified by the lamp.
it was a EHD lamp if that helps

[gafftaper]

Hold on so you had already removed it from the base? Exactly how were you holding it? What part did you touch with the other hand? You know you can't give yourself a shock so the charge would have to be insulated between the one hand and the other somehow. I've read things about ancient glass jar capacitors that aren't that much unlike a lamp turned upside down.

SHIP!!... We need your help on this one big guy!

[avkid]

What were you standing on/near?
It could just have been a huge static build up that used the lamp as a conductor.

[derekleffew]

norwintd, you had FIRST unplugged the fixture before removing the lamp cap, right? Just wanted to eliminate the possibility of an electrical circuit between: What you were standing on -> your feet -> your hand -> lamp cap -> grounding pin -> building's electrical ground. Was it dry that day in Irwin, PA? What was the relative humidity inside your building? I feel that gafftaper's "I've read things about ancient glass jar capacitors that aren't that much unlike a lamp turned upside down," hypothesis is plausible, and worth exploring. Did you save the 500W EHD lamp? What was the make and model of the fixture in question? What color, if any was inside the glass envelope? Was there an obvious break in the filament? What brand lamp? This may sound sadistic, but are you able to re-create the incident? Peculiar that norwintd describes "like getting shocked by a car battery and the sting lasted for a minute or so." Car (all) batteries are DC.

Since Ship is our resident expert on "all things lamps," I look forward the hearing his thoughts.

[Van]

Originally Posted by gafftaper

.......................... I've read things about ancient glass jar capacitors that aren't that much unlike a lamp turned upside down...................
!

Yeah, but a Leyden Jar, <early battery/capacitor>, has to have some form of electrolyte inside the glass envelope. While it would be plausible to think that the two leads could act as electrodes for the "Battery" what would act as the electrolyte. We know that the halogen gas in the envelope is "Noble" and therefore incapable of holding a charge. If there were an even microscopic hole in the envelope, which happens occasionally, it could have let in some atmosphere, which is often what causes the cool discolorations on the inside of blown lamps. Perhaps, some form of Tungsten oxide could then have been suspended inside the lamp. Now for this to work properly, the envelope would have to have been breached, the filament blown, and the envelope then resealed in very short order. So let's say a microscopic hole develops, atmosphere rushes in, oxygen reacts with filament creating Tungsten Oxide Gas, Filament breaks at weak point caused by oxidation, white-hot filament hits Quartz envelope at precisely the point where the microscopic hole had developed, White-hot filament causes quartz envelope to melt and re-seal itself resealed envelope contains some bizarre ionic compound hither to unknown to modern science, Said Ionic compound then stores a static charge not unlike a Leyden Jar of old, and then Shocks the heck outta poor Norwintd.

How's that ?
For an experiment hold the glass in a set of insulted pliers, rub it up and down someone wearing a wool sweater, then bring the contacts close to something metallic and grounded, like a piece of bare conduit, to see if it discharges.

[JD]

No big Ham Radio rigs around? I remember a girl that got her butt zapped sitting on a sofa while her boyfriend was keying his rig in the next room!

[Logos]

Can't wait to hear some more on this one. I love Van's explanation for turning a lamp into a Leydon Jar. I am not tempted to experiment.
Everything that can possibly happen eventually will.

[norwintd]

ok guys i will try to answer some of the questions

yes it had been removed from the base by one of my students carried from the stage to our storage room behind our light booth. probably about 75 foot walk. He handed it to me. i had it in my hand for a 20 -30 seconds then I got nailed. I believe i had it by the base in one hand and hit the glass with the other. The filament was broke and there was a hole melted through the glass after i got shocked(not sure if the hole was there beforehand)

I do still have the lamp I will take a closer look at it tomorrow.

I think avkid is on the right track. After thinking about it, our storage room is actually part of the circulation system for the auditorium it has two large air handlers in a not so large room. I think the room became one big static chamber
and the lamp became the conductor


I will see if i can recreate the occurrence, the weather is staying about the same the next few days so conditions should be similar.
Ill let you guys know
and hopefully Ship will drop in with some help

[Footer]

Originally Posted by norwintd

ok guys i will try to answer some of the questions
yes it had been removed from the base by one of my students carried from the stage to our storage room behind our light booth. probably about 75 foot walk. He handed it to me. i had it in my hand for a 20 -30 seconds then I got nailed. I believe i had it by the base in one hand and hit the glass with the other. The filament was broke and there was a hole melted through the glass after i got shocked(not sure if the hole was there beforehand)
I do still have the lamp I will take a closer look at it tomorrow.
I think avkid is on the right track. After thinking about it, our storage room is actually part of the circulation system for the auditorium it has two large air handlers in a not so large room. I think the room became one big static chamber
and the lamp became the conductor
I will see if i can recreate the occurrence, the weather is staying about the same the next few days so conditions should be similar.
Ill let you guys know
and hopefully Ship will drop in with some help

I doubt its acting as a capacitor with that long of a walk. You probably got a static shock. Now... every time I have got hit by 120, it tends to be a "warmer" shock, I think you were describing a quicker more high voltage shock like a static shock would be.

[Van]

Originally Posted by Footer4321

I doubt its acting as a capacitor with that long of a walk. .....................

But, you have to admit........ It is possible.