[volt-nuts] Integrator errors from dielectric soakage?

[Andreas Jahn]

> Any ideas as to how much error the (presumably) Mylar integrator cap
> will introduce? In other words, will such error be significant in a
> mere 3.5 digits? 

Hello,

several years ago I built a integrating ADC.
2.5V Reference as "zero voltage" and integrating +5V and 0V 
against the input signal.
(0 .. 5V measured as -2.5 to 2.5 V).

Due to capacitor soaking I had a gap in the middle of the 0 to 5V 
range which was about 1mV (0.02%) as non linear jump. 

I could reduce the non linearity by replacing the mylar capacitor with
 a polypropylene capacitor by a factor of around 10.
 
So for a meter with 3,5 digits this should not play a role.

With best regards

Andreas