ADC sampling of voltage >500V

[samuelr]

Hi

I am thinking of sampling a 500Vdc line but I like to be as accurate as possible.
The device I am using (16-bit adc) to sample it has a range of 20V (-10V to 10V). This is selectiable to even 2V. I know that I have to use a voltage divider to bring down the voltage to the level that will not damage the meter but. I am thinking if I should use the 20V range or the 2V range. I believe that the 2V range should give me a better accuracy.
I am just looking for someone that might have other suggestions or disagrees.

 

[Zaphappy]

Your probably correct that the 2V range will be more accurate. The 20V range most likely has a divider and therefore has an additional ratio error.