  We investigate the influence of the high voltage scheme elements on the
stability of a detector based on a single $10\times10$ cm$^2$ area GEM with
respect to the secondary discharge occurrence. These violent events pose a
major threat to the integrity of GEM detectors and their Front-End Electronics
and need to be avoided by any means. For a single GEM setup, we propose a
detailed high voltage scheme that is designed to prevent secondary discharges.
We determine optimal values of the protection resistors and parasitic
capacitances introduced by cables used in the system. The results of this paper
may be used as a guideline for the optimization of more complicated multi-GEM
detectors.
