Diagnostic method and apparatus for a pressurized gas supply system

A pressurized gas supply system including:

• a. a source of compressed gas;
• b. a supply line adapted to communicate with a receiving vessel for delivering compressed gas to said receiving vessel from the source of compressed gas;
• c. a control valve in the supply line operable between opened and closed conditions to control the flow of gas through said supply line into the receiving vessel;
• d. a flow controller for controlling the operation of the supply system to deliver compressed gas from the source of compressed gas to the receiving vessel through the supply line and the control valve at a desired ramp rate, said flow controller also being operable to close the control valve in the event of a malfunction resulting in the pressure of gas being directed into the receiving vessel exceeding an upper limit of a percentage deviation that is set relative to an intended pressure at the desired ramp rate;
• e. a pressure monitor downstream of the control valve for continuously measuring the pressure of gas being directed into the receiving vessel and continuously transmitting a signal representative of said pressure of gas to said flow controller, said flow controller comparing the actual pressure of gas with the intended pressure at the desired ramp rate and operating the control valve to a fully closed position if the actual pressure exceeds the upper limit of the percentage deviation.