Re: Field Mills (fwd)

[Steven Roys <sroys@xxxxxxxx>]

---------- Forwarded message ----------
Date: Sun, 11 Jul 2004 09:51:07 -0300
From: Antonio Carlos M. de Queiroz <acmdq@xxxxxxxxxx>
To: High Voltage list <hvlist@xxxxxxxxxx>
Subject: Re: Field Mills (fwd)

High Voltage list wrote:

> From: Matthew Smith <matt@xxxxxxxxxx>

> Even in an indoor lab setting, I think it would be a good idea to isolate from
> your (expensive) equipment using internal opto-isolators.  I think Antonio's
> problem shows a good example of this.  Those meter terminals should have been
> via an opto-isolator.  When you connect the wrong thing to them, you burn out
> the opto-isolator.  Unplug and put in a new one for $1...

Indeed, one of these field mills fried the serial port of the
controlling computer when I tried to observe the field generated by a
large electrostatic machine in front of it. Or possibly it was not
even powered, but just there connected to the computer, serving as
a capacitive antenna, while the machine was producing long sparks
one meter away.

Antonio Carlos M. de Queiroz