Measuring High Voltage with Influence

AI Thread Summary
Measuring the voltage of a Kelvin Water Dropper can be challenging due to its high voltage and low charge. Suggestions for measurement include building an electroscope, using an electro field meter, or creating a generating voltmeter that employs a rotating fan to alternate exposure of capacitor plates. This method allows for the detection of voltage through capacitive coupling, even with DC sources like Van de Graff generators. The generated AC signal can then be measured with a high impedance scope or meter, providing a non-contact measurement solution. Overall, these techniques focus on utilizing influence and capacitive methods for accurate voltage measurement.
triac
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Hi!
I am looking for a way to measure the voltage on a Kelvin Water Dropper that I've built. This is quite problematic since the charge is small and the voltage is high. The only way to do it, as it seems to me, is to measure by influence. Any suggestions?
 
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You could also use the field. Some suggestions:
- build a simple Electroscope with an arm that moves up if the device is charged (some have a scale)
- buy an electro field meter
- attach your buckets to a plate capacitor and rotate a coil inside
- measure the force between two capacitor plates
- do something with a cathode ray tube
 
triac said:
Hi!
I am looking for a way to measure the voltage on a Kelvin Water Dropper that I've built. This is quite problematic since the charge is small and the voltage is high. The only way to do it, as it seems to me, is to measure by influence. Any suggestions?

Build a generating voltmeter. This is a rotating "fan" that alternately covers and uncovers capacitor plates. Feed the plates behind the rotating part to a high impedance scope or other High Z AC meter. AC signal will be proportional to the high voltage without contact. These are commonly used to sense the voltage on Van de Graff generators.
 
Ok, thanks for your help!
 
bjacoby said:
Build a generating voltmeter. This is a rotating "fan" that alternately covers and uncovers capacitor plates. Feed the plates behind the rotating part to a high impedance scope or other High Z AC meter. AC signal will be proportional to the high voltage without contact. These are commonly used to sense the voltage on Van de Graff generators.

How can this work if Van De Graff generators produce DC power?
 
taylaron said:
How can this work if Van De Graff generators produce DC power?

The rotating "fan" alternately shields and exposes the voltage on the target, producing an AC signal via capacitive coupling.
 
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