Method of operating a helium leak detector and helium leak detector suitable for carrying out this method

摘要

Method for operating, a helium leak indicator (1) consisting of a helium detector (4) with evacuation devices comprising at least a high-vacuum pump (6), a backing pump (9) and a valve (16) whose level of flow conductance can be adjusted and serves to modulate the through-flow of test gas to be analyzed; in order to influence the sensitivity in a simple manner, the method provides that the modulation properties be changeable in such a manner that the effective pumping capacity at the inlet of the leak indicator is changed by the adjustment of the modulation properties.