Losing Your Fear of the ZERO Function

A standard feature on all helium leak detectors, the "zero" button adjusts the sensitivity of the unit to help detect smaller leak rates. New users may not be familiar with its function, and often, they feel apprehensive about pushing "zero" for fear of missing a key leak rate signal (as the button turns off the readout). But remember, the zero function is one of the most important buttons on a leak detector!

By pushing the "zero" button, the processor stores the ongoing leak rate and subtracts it from any further measurements - switching the leak detector to a more sensitive range, which helps find smaller leaks easier. This is a very effective way to find leaks even during the presence of an interfering background signal, for example, sniffer leak detection with a helium background of 5ppm in the ambient air. If the background signal is unstable, simply press the "zero" button just before you direct the probe tip at the assumed leak area.

When taking measurements in a vacuum chamber with a falling background signal, the "zero" enables earlier detection of the reject leak rate. This shortens the measurement times and increases the number of tested parts per shift. But the operator's fear is that the decreasing background could pull the signal below the zero line of the display and hide a small leak rate signal; the floating zero adjustment capability - a unique feature of INFICON leak detectors - is a reliable solution to that problem. The signal is measured continuously and the zero rate is reduced step by step while the background signal falls. The graph below demonstrates how a leak of 5⋅10^-10 mbarl/s can be detected precisely, even with a background signal in the 10^-9 mbarl/s range.

Unique Feature: The floating zero adjustment capability found in INFICON leak detectors provides clearer detection signals at lower leak rates.

Click here to learn more about INFICON helium leak detectors »