Electrostatic state determination for checking electret filter, involves applying potential set such that sign of sensor current is same as sign of sensor current caused by absorption of ions, to amperometric probe

摘要

A sensor of an amperometric probe is introduced into a gas flow and a specific potential is applied to the probe for measuring the primary sensor current caused by the absorption of ions. A secondary potential is applied to the probe such that the sign of the secondary sensor current is the same as the sign of the primary sensor current. An electrostatic variable is determined from the applied potentials and detected sensor currents. An Independent claim is also included for an electrostatic state determining device.