At the end of the 1980s improved electrode materials led to higher capacitance values.
Symmetry implies that both electrodes have the same capacitance value.
In this case the required capacitance value has to be recalculated for every application condition.
They have no significant aging processes and the capacitance value is nearly independent from the voltage applied.
Hence the capacitance value of class 2 capacitors is nonlinear.
Cracks are usually detected by a short circuit or a change of the capacitance value in the deflected state.
Note: This is only correct if all capacitance values are equal.
This allows for a higher voltage rating or capacitance value using a smaller total volume.
The capacitor's plate area can be adapted to the wanted capacitance value.
The actual capacitance value should be within its tolerance limits, or it is out of specification.