Re: Electrometer insulators (fwd)

["High Voltage list" <hvlist@xxxxxxxxxx>]

Original poster: Steven Roys <sroys@xxxxxxxxxx>



---------- Forwarded message ----------
Date: Tue, 31 Oct 2006 16:35:44 +0800
From: Peter Terren <pterren@xxxxxxxxxxxx>
To: High Voltage list <hvlist@xxxxxxxxxx>
Subject: Re: Electrometer insulators (fwd)

I am surprised that you hope to measure minute charges in the presence of 
rotating magnets that will induce fields and currents in everything metallic 
unless you have huge shielding against both static fields and varying 
fields. But I have little background in electrostatics if that is even what 
you are planning.

Peter
http://tesladownunder.com




> ---------- Forwarded message ----------
> Date: Mon, 30 Oct 2006 20:09:18 -0500
> From: Richard Hull <rhull@xxxxxxxxxxxxxx>
> Sapphire is the normal super insulator of choice in high end electrometer
> work.  Polystyrene and teflon are about an equal #2.
> Richard Hull
>
>> ---------- Forwarded message ----------
>> Date: Mon, 30 Oct 2006 9:11:32 -0800
>> From: David Dameron <ddameron@xxxxxxxxxxxxx>
>> To: High Voltage list <hvlist@xxxxxxxxxx>
>> Subject: Electrometer insulators
>> Does anyone know of a web page with characteristics of insulators 
>> suitable
>> for electrometer work? I am investigating an experiment with a metal box
> which would hold gel-cell batteries, a motor, rotating magnets, etc. The 
> charge
> which  could be induced on the box is in the range of  10E-14 Coulomb. 
> This
>>metal box would be enclosed in and insulated from an Faraday cage.
>> One candidate is polystyrene, say 4 columns 10cm long. I know teflon is
>> good for small printed-circuit use, but do not know how it would perform
> in this
>> type of use. The insulator should not be too much piezoelectric, with
>> likely vibrations from the rotating elements.
>>
>> -Dave D.