Agilent Technologies G8610A Operation Manual page 62

62
Agilent Technologies Helium Leak Detector
Pressing Zero while introducing helium tracer gas to the test
NOTE
object, or while the helium background is varying significantly,
could result in the suppression of a real leak. Only use the Zero
button after the helium tracer gas source has been removed.
The Zero capability allows the testing of sensitivity levels that are
below the system background. This feature also reduces test cycle
times by reducing the amount of time required for background lev-
els to naturally clean up or by allowing testing to begin at relatively
high test pressures. It is recommended to zero out only two
decades of signal.