Electric charge much lower than expected in plate capacitor

Hi there,

the charge I get from global evaluation is much lower than expected on my terminals.

My model is a bending beam, which should touch the bottom of a cavity by electrostatic attraction. I started off with electrostatics, but global evaluation of the terminal charge returns a 1E-9 smaller value.

Preliminary considerations are based on a plate capacitor ( Q = V * C ) with 30 V potential difference, 20 mm^2 plate area, 70 um plate distance and the relative permittivity is 80. This results in a charge of about 6.07 C. But global evaluation of the terminal charge returns 6.06E-9.

However, when I set the terminal constraints to charge, an electric field is not generated at all.

Any idea where I could be mistaken?

Thanks in advance,

Jonas