FW: NON-static shocks from unpowered secondary?

["Tesla list" <tesla-at-pupman-dot-com>]

Original poster: "Lau, Gary by way of Terry Fritz <twftesla-at-qwest-dot-net>" <Gary.Lau-at-compaq-dot-com>


Patrick Leonard, the originator of this thread is having email troubles and
asked me to post his response:

 

Patrick wrote:

I'm responding to you directly since my email with the list is messed up. If
you wouldn't mind posting this, along with your response back to the list, that
would be great.

 

Gary wrote:

>Normally, the base of the secondary coil is tied to ground.  You say that
>you get shocks from touching either terminal of the coil.  How can you get
>a shock from touching the grounded end of a coil, unless YOU are at some
>elevated voltage?  

 

Patrick replied:

The shocks I'm talking about occur when the coil is physically removed from the
tesla system. It could be on the other side of the room for storage. Both ends
are "free". 

 

Gary wrote:
>I'm assuming that by "unpowered secondary", that you mean that the Tesla
>Coil is not running.  Or do you mean that there is an operating Tesla Coil,
>and near by is another, unconnected secondary coil, and it's this secondary
>that is shocking you?  This would be no surprise.

 

Patrick replied:

The tesla coil is not running (nor is any other tesal coil) and the coil is
completely removed from the rest of the system. As mentioned above, I could be
putting the coil away for storage or something. 

 

Gary concludes:

Ahh, I see!  A static DC charge is the only possible source of energy that
could persist for a time span of seconds after turning off the power.  There is
no mechanism to keep an AC oscillation alive for so long.  If the ground
connection to the base of the coil is disconnected after the coil is turned
off, then the coil and top load could become charged to a DC static potential
relative to ground from the static charge that accumulated on the surface of
the secondary.  

 

Regards, Gary Lau

MA, USA