RE: Electrostatic Meters - AC not possible

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

Original poster: "John H. Couture by way of Terry Fritz <twftesla-at-qwest-dot-net>" <couturejh-at-mgte-dot-com>


Dan -

The electrostatic meter has no electronics unless you call two metal vanes,
one fixed and one moving as electronics. When an AC or DC voltage is applied
to the vanes of an electrostatic meter the oposite charges on the vanes will
attract one another causing the needle to move. Unlike meters that use
currents the electrostatic meter requires only an initial charge of current.
This means that the circuit being tested is very lightly loaded. If the
voltage is AC the charges are alternating but the force is still attraction.
The same scale can be used for both AC RMS or DC. The AC waveform is not
important as only the RMS value is used. The electrostatic meter has the
advantage that over voltages within reason will only flash over between the
vanes because there are no coils to burn out.

Do not confuse with so called moving vane meters which work by currents.
These meters use coils and work by magnetic forces. Note that electroscopes
are different than electrostatic meters because they work by the replusive
force of like charges. The electrometer is a device that uses electronics
and works by using currents and magnetic forces. Then there is the
electrostatic wattmeter! Electrical meters cover a large field of electric
and magnetic forces.

John Couture

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-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Tuesday, November 12, 2002 4:43 PM
To: tesla-at-pupman-dot-com
Subject: RE: Electrostatic Meters - AC not possible


Original poster: "Mccauley, Daniel H by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <daniel.h.mccauley-at-lmco-dot-com>



Is this meter a true electrostatic meter or does it have internal
electronics????

Dan



Dan -

I have an Electrostatic Kilovolter made by Hallmark Standards, Inc. It reads
from 0 - 2000 volts, AC or DC, Tolerance +/- one percent. I have tested the
E. meter for AC RMS and it is right on the mark. This E. meter will read AC
RMS or DC volts using the same non linear scale. Both terminals are
insulated and the meter is in a non metallic case.

John Couture

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-----Original Message-----
From: Tesla list [mailto:tesla-at-pupman-dot-com]
Sent: Tuesday, November 12, 2002 6:21 AM
To: tesla-at-pupman-dot-com
Subject: Electrostatic Meters - AC not possible


Original poster: "Mccauley, Daniel H by way of Terry Fritz
<twftesla-at-qwest-dot-net>" <daniel.h.mccauley-at-lmco-dot-com>



To prove that AC measurements using a electrostatic meter is NOT possible, I
went into our lab today and tried measuring 4000VAC (60Hz) using both an EIS
electrostatic meter and a Sensitive Research type electrostatic meter.

For each test, the negative terminal of the electrostatic meter was grounded
and connected to the return for the 4000VAC
source.  A true RMS multimeter with a high voltage probe was used to verify
any readings.

In each instance, the multimeter read the nominal 4000VAC rms, but the each
electrostatic meter read ZERO volts.

To verify the electrostatic meters were working i switched the source to
output 4000VDC and voila, the electrostatic meters both read 4000V on the
nuggin' !

Dan