Detailed Explanation of Leak Detector Operating Principle

The test cycle is normally initiated by a signal from the Test Station Photoswitch. The test head cylinder valve is turned on, bringing the test head down to seal on the bottle. At the same time, the pressurization valve is turned on, allowing the bottle to pressurize. When the pressure in a bottle rises past a threshold, the pressurization valve is turned off. After a short delay, the pressure in the bottle is measured (Pressure A). The bottle remains sealed for the remainder of the test time. At the end of the test, the pressure in the bottle is again measured (Pressure B). The test head is then retracted.