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Can a neon sign transformer with an output of 12000V and 30mA kill you?
retrolefty:
From the Wik:
--- Quote ---Magnitude[edit]
The minimum current a human can feel depends on the current type (AC or DC) as well as frequency for AC. A person can feel at least 1 mA (rms) of AC at 60 Hz, while at least 5 mA for DC. At around 10 milliamperes, AC current passing through the arm of a 68-kilogram (150 lb) human can cause powerful muscle contractions; the victim is unable to voluntarily control muscles and cannot release an electrified object.[5] This is known as the "let go threshold" and is a criterion for shock hazard in electrical regulations.
The current may, if it is high enough, cause tissue damage or fibrillation which leads to cardiac arrest; more than 30 mA[6] of AC (rms, 60 Hz) or 300 – 500 mA of DC can cause fibrillation.[7][8] A sustained electric shock from AC at 120 V, 60 Hz is an especially dangerous source of ventricular fibrillation because it usually exceeds the let-go threshold, while not delivering enough initial energy to propel the person away from the source. However, the potential seriousness of the shock depends on paths through the body that the currents take.[7] If the voltage is less than 200 V, then the human skin, more precisely the stratum corneum, is the main contributor to the impedance of the body in the case of a macroshock—the passing of current between two contact points on the skin. The characteristics of the skin are non-linear however. If the voltage is above 450–600 V, then dielectric breakdown of the skin occurs.[9] The protection offered by the skin is lowered by perspiration, and this is accelerated if electricity causes muscles to contract above the let-go threshold for a sustained period of time.[7]
If an electrical circuit is established by electrodes introduced in the body, bypassing the skin, then the potential for lethality is much higher if a circuit through the heart is established. This is known as a microshock. Currents of only 10 µA can be sufficient to cause fibrillation in this case
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uncle_bob:
--- Quote from: Florin on February 01, 2016, 08:08:52 pm ---I just saw a video https://youtu.be/EOVpldbaGq4?t=24s where this transformer is limited to 30mA and I was wandering if it can kill you.
(PS: It's my first post and i'm not sure if i choose the correct category).
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Hi
Here's the trick that you may see:
You take the neon driver transformer and convert it's output to RF (with a Tesla Coil). You get marvelous looking arcs. The current can be quite high. Since it's RF, your body reacts differently to it than to DC or low frequency AC. You can still get burns (energy -> heat). You don't get the same interaction with the nervous system. It's a great way to do dramatic demo's. It's also a good way to give people the wrong impression about electrical safety.
30 ma at a couple of KV (DC or low freq AC) will knock you across the room from the muscle contraction.(no it does not knock you, your muscles knock you, the result is the same and it hurts). Yes I have empirical data ...
Bob
janoc:
Oh and don't forget the lovely deep burns through the tissue where the arc has shot through. Those take very long time to heal and if they get infected because of the dead tissue deep in the muscle, you can end up with sepsis or an amputation.
That is not a voltage to take on lightly, even if it was just 1-2mA and not 30.
CatalinaWOW:
The following link implies that neon signs have killed at least one person, but probably not dozens and dozens. (It is interesting reading overall on the topic of electrical safety.)
http://apps.ocfl.net/dept/county_admin/public_safety/risk/Construction_Workers_Getting_Electocuted.pdf
Anecdotes from people on various forums (including this one) show that many people survive contact with these supplies. All mention that it was absolutely no fun. Very painful and frightening. My own experience with a lesser source confirms this.
Seems like treating it as if it could kill you is a smart move. Even if you don't save your life you will avoid a lot of pain.
Brumby:
--- Quote from: CatalinaWOW on February 02, 2016, 03:21:29 am ---Anecdotes from people on various forums (including this one) show that many people survive contact with these supplies.
--- End quote ---
That has been said on many occasions about supplies that are eminently capable of killing. Any reader should not take that as an observation, not an invitation to regard them with any less respect.
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