Arduino measuring high-voltage electric fence I would like to know if someone has experience with measuring high voltages using an Arduino.
I know you can use resistors to lower the voltage, however.
I want to be able to measure the pulses of an electric fence used to prevent farm animals from escaping. These pulses are high-voltage and will not always be a similar voltage. I want to read these voltages, to scan for differences.
So, I wondered if someone has done something like that, and if the Arduino gets weird when it gets a voltage above 5V at a low amperage on its analog port.
--here some possible solutions for those wanting to know the answer--
-mostly based on comments and answers below-

Using resistors as a voltage divider while keeping an eye on the maximum spark gap distance and capacitive coupling.
using a transformer/coils to reduce the voltage.
using a high voltage probe to measure it.
using neon bulbs or other light sources to measure it.
charging a capacitor and measuring discharge time with high resistance(only works for the total power)

-this list is meant as a summary of what is discussed further ideas and solutions are still welcome-
You are talking about measuring 2kV to 10kV pulses, with about 1J to 5J of energy per pulse.
The maximum current may be very low, but the voltages you want to measure are very high, and will very probably damage your Arduino without proper measures.
You will at least need a voltage divider to reduce the voltage the Arduino sees to 5V (or 3.3V for some Arduinos) to be able to make a measurement with the Arduino's ADC.
The voltages are high enough to bridge a fair distance with a spark; they could well bridge a physically small resistor or the distance between two connections on your breadboard or PCB.
To be honest, I think you shouldn't go anywhere near such voltages with an Arduino, unless you know exactly what you are doing when preparing the signal for an Arduino's ADC pin.