Abstract: The specification discloses an electronic dynamic balance leak testing system utilizing a "live zero", wherein a source of test medium at a predetermined desired pressure or vacuum is connected to a part to be tested, and after the part is filled with the test medium, and an interval is provided for the system to stabilize the affects due to wave front oscillations, the test part is momentarily isolated from said test media and a microcomputer system is utilized, both to cause said isolation, and to measure the differential pressure existing at two points during the test. In a modification of our system which can dynamically project leak and accept or reject parts much sooner because of this projection feature, the rate of change of the differential pressure transducer is examined and is compared to a curve which is characteristic of the rate of change of a volume which is experiencing a predominately leak based change of pressure.

Abstract: The specification discloses a method and apparatus for calibrating liquid flow meters of all types. The system includes a scale for dynamically determining the weight of a liquid flowing through a flow meter, together with means for measuring the flow through the flow meter being tested. In the case of a glass tube flow meter, a float detection system is used, whereby the operator will set the flow through the flow meter to a desired point, use the float detection system to make certain the float stays in a fixed position during the test, as well as to locate the float from a reference point, and use the system to measure the flow through the flow meter during a fixed period of time, thereby obtaining a reading, in engineering units, for each predetermined position of the float.

Abstract: The specification discloses a method and apparatus for detecting the position of the float in a glass tube flow meter, and determining the distance of said float from a reference line on the glass tube flow meter which is being calibrated. The blockage of an infrared light beam being sent from a transmitter to dual photo receivers, coupled to an optical conditioner circuit, provides an indication of whether float is high, low or in-band in relationship to the desired position, while a float follower, which is movable along the length of the flow tube by a stepper motor which is connected to a pulse encoder, provides through an optical conditioner circuit, an indication of the float position with regard to the reference line on the glass tube. The circuitry also provides for the automatic tracking of the float as its position is changed by the operator.