Static discharge from metal tv stand

[JT]

This may sound completely irrelevant to some, but it freaked me out. In one of my rooms I have my 27" TV and VCR mounted on the wall with one of those heavy duty rotating stands with a carriage under it for the VCR; kind of like you would see in a hospital or hotel. I have been experiencing some color fluctuation and a lot of dust built up on the TV. There is no ground on either my tv or vcr. When I went to clean my tv screen yesterday, when I sprayed the TV with cleaning solution, my tv stand started arcing to the metal case on my vcr. Were talking an official arc that lasted a few seconds. It was enough current to resent the info in my vcr and shock me real damn hard. I've been shocked many times, and that was one hell of a jolt considering it was nothing but static that had built up on the ungrounded metal stand and TV screen. Has anyone ever heard of this? It seems to me like the mounting unit/stand should have come with a grounding wire or something. So I ran a wire from the stand to a solid ground. I think that should take care of any future problems. I am interested in hearing comments on this phenomon. My IRD sits on the table underneath the TV, and was unaffected. I am virtually positive that it was just static build up. I do not think there is anything wrong with my TV or VCR. The color fluctuation in the corner of the TV is gone now as well. Any thoughts?

[sub56]

Maybe you drilled your bracket into a power cord....

[niknak]

Jack
Be carefull. What you described is a polerazation problem between two AC devices. If you measure the TV to VCR grounds you will see the 120vac potential. That's why the AC plug on all AC appliance connectors have a large pin and a small pin. That's so the plugs polerize correctly and not shock you. Yours looks like one device is not polerized correctly.

The best way to verify that is to mesure the voltage between the wall ground pin to each chassis ground. One will read a voltage, one won't. Fix the wrong one that reads the voltage. If you don't have a meter put some dry shoes on. Put the back of your hands hair on top of the metal chassis ground on each device ONE AT A TIME. The one you feel your hair move is the one that is not polerized correctly. Just rotate the plug on the wrong one or do something to repolerize the plugs. Sometimes the AC source in the wall is not polerized correctly.

niknak

[JT]

My recepticles/outlets in the wall and the ends of both my TV and VCR cords will not allow what you just described niknak. In both cases the plugs are shaped to fit only one way, and on both ends of the power cords. I am convinced that it was just the result of months of static build up. It's not as if the problem begins as soon as I put power to the units, it takes a long time to build up; at least a few months. In about 5 years of having the TV mounted like it is, this is the first time something like this has happened. I think the small electric field generated in the air by the TV screen just built up in the metal stand and had no where to go until.... I think the clincher is the degousing effect I got when I cleaned the outside of the screen and grounded the charge out of the stand. I'm still very interested to hear if anyone else has had something like this happen or if there are any other theories.

[slimthugga]

i guess thats why they say to ground sat dishes??????

[Killer-D]

Static Electricity can do some pretty amazing things.

I would think that depending on the design of the metal stand you could basically have a giant capacitor and the static field of the tv is what is charging it. Although I would think that unless you have your tv turned on all the time that the charge would bleed off eventually.

Many years ago I worked at the SuperCollider, if you dont know what the SuperCollider is, never mind its not important. We used to test our magnet designs in vats of oil to keep them from arcing. When we wanted to change something on the magnet we would pump the oil into large plastic barrels. Just the effect of the oil swirling around inside the plastic barrel as it filled up was enough to generate a HUGE amount of static electricity. By the time the barrel was full, all of the absorbent material we had spread out on the floor was stuck to the side of the barrel. Of course then one of us had to remove the hose and put it in another barrel, that was the test of who the REAL men were. hehe. Was good for a little intern training too. :)

[4x4]

This may sound completely irrelevant to some, but it freaked me out. In one of my rooms I have my 27" TV and VCR mounted on the wall with one of those heavy duty rotating stands with a carriage under it for the VCR; kind of like you would see in a hospital or hotel. I have been experiencing some color fluctuation and a lot of dust built up on the TV. There is no ground on either my tv or vcr. When I went to clean my tv screen yesterday, when I sprayed the TV with cleaning solution, my tv stand started arcing to the metal case on my vcr. Were talking an official arc that lasted a few seconds. It was enough current to resent the info in my vcr and shock me real damn hard. I've been shocked many times, and that was one hell of a jolt considering it was nothing but static that had built up on the ungrounded metal stand and TV screen. Has anyone ever heard of this? It seems to me like the mounting unit/stand should have come with a grounding wire or something. So I ran a wire from the stand to a solid ground. I think that should take care of any future problems. I am interested in hearing comments on this phenomon. My IRD sits on the table underneath the TV, and was unaffected. I am virtually positive that it was just static build up. I do not think there is anything wrong with my TV or VCR. The color fluctuation in the corner of the TV is gone now as well. Any thoughts?

JT , put a board in between the TV and the stand ..
Also don't spray the cleaner right on the TV , srpay it on a cloth first ...

[mr.jeepster]

that happen to me too,but no lighting bolt to my vcr.Dont ever clean a tv like that,spray it on rag and clean it.That picture tube can hold a charge for a long time and zap you hard( when its off too) my grandpa use to fix tv's years ago and told me storys about that,those sucker have 80,000 kv volts to them when charged up.You did the right thing with the ground strap,but put a connector on that wire you have for a ground to the face plate screw hold down or a good ground-good luck

[JT]

Yeah, I don't turn my TV off very much. I can't sleep without it on....I know, your not supposed to do it that way. And yes, next time I will spray the cleaner on the rag first. I'm telling you guys, it was like my tv stand was plugged in for a few seconds. It was very suprising. Now the stand is grounded to the recepticle, so that should never happen again. In hindsight, I guess it's not all that suprising, I just never thought of the elecromagnetic field from my TV generating a charge in the metal stand until now. The design of the stand is perfect for acting as a capacitor.

[mr.jeepster]

after you got shock good,you respect the laws on electric!you had no ground on the wall at all( studs=wood none conductor) you made the complete curcuit!

[JT]

Yeah, I got to thinking about it; my TV stand is a large C shaped metal object with a metal clamp on the top and a metal plate on the bottom, with the TV right in between. The metal parts are less than an inch from the screen. In hindsight, it's not suprising at all that static charge could have built up in the stand. Oh well, now it's grounded just as if you were grounding a metal recepticle box for an outlet. It won't happen again.

[cojones]

Damn a free buzz what are you complaining about?