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Re: Definitions of High Voltage



Original poster: "Barton B. Anderson by way of Terry Fritz <twftesla-at-qwest-dot-net>" <tesla123-at-pacbell-dot-net>

Hi Jonathon,

Tesla list wrote:

> Original poster: "by way of Terry Fritz <twftesla-at-qwest-dot-net>"
<Kidd6488-at-aol-dot-com>
>
> As
> per North's paper (High Voltage Insulation, pg1), any voltage below
> approximately 340V will not discharge through
> air, regardless of spacing or barometric pressure
>
> what about 120 VAC? ever unplug sumthing while its still on? Those are the
> same sparks you get from 12kV...
> ---------------------------------------
> Jonathon Reinhart
> hot-streamer-dot-com/jonathon

Yes I have. Whenever you open a closed contact (wall plug, relay,
whatever), an arc
is possible. It depends on the load power and how the variation of contact
resistance changes as the contact opens. As the resistance changes, the voltage
inversely follows, and when high enough will ionize the gas to arc the gap
created
as the contact is just opened. The arc can also be pulled much longer than it's
initial allowable gap arc distance once the gas is ionized and conducting
current.

Thus, 120Vac at the wall plug does not mean the voltage that caused the arc was
120Vac. As a matter of fact  -  definately not.

Read up on relay's (voltage produced by opening contact). It's the opening that
causes the contact deterioration. Even when a relay is closed, it bounces
and opens
on each bounce causing deterioration of the contacts.

Regardless, I was talking about arcing across an open gap (no initial contact
required). Thus, at whatever voltage "that" is, I see that as "high
voltage". But
hey, that's just my definition. Bottom line for me is, if I shock is possible
without physically touching the "whatever", then I consider it high voltage.

Take care,
Bart