Static electricity/Measuring high voltages

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Problem[edit]

How are voltages of 600,000 volts measured? The actual voltage created during static discharge to a doorknob may be measurable.

Conceive[edit]

Looking at the length of the spark, the voltage can be estimated. But there has to be a way to measure the actual voltage. Requirements are:

  • convincing safety precautions
  • certification tutorial
  • demonstration video

Design[edit]

Show how measuring voltage is done by measuring how far apart leaves of metal become in the presence of the static field.

Draw diagrams showing how the high voltage probe should be connected to a DVM and to the high voltage source.

Implement[edit]

The HP High Voltage Divider Probe (Model 3411A) is to be used to extend a DC voltmeter's measurement range by a factor of 1000.

A manual for it can be found here
It is recommended that the operation section of the manual be read for safe operation

Voltage Probe.jpg

Operate[edit]

The probe is designed to allow a normal voltmeter, such as one that has a range of 0-20 volts, to measure voltages 1000 times the original, extending the range to 0-20k volts.

Maximum Voltage: 40k volts
A division ratio of 1000:1, meaning any voltage measured will be stepped down by a factor of 1000.
The voltmeter will read out should be multiplied by 1000, so If 15.2 is displayed, it means the voltage measured is 15200 volts.
Hook up the COM lead to the voltmeter common (ground) and input terminals.
Ensure to clamp the earth ground lead to an earth ground, such as a grounded metal door frame.

High Voltage probe input and ground leads.jpg

Demo[edit]

Next Steps[edit]

  • Review high voltage safety
  • Find procedures at NIST
  • Develop test procedure
  • Predict test statistical results
  • Generate static on balloons, human body and measure