Gas supply system to provide a continuous supply of gas from at least two finite gas sources

摘要

A gas supply providing a continuous supply of gas from a gas source comprising at least first and second finite gas sources 1, 2, comprising: at least one gas inlet 7 for receiving gas from the gas source; a selector 9 for selecting which of the gas sources is to supply the gas supply system; a gas outlet 8 for providing a continuous supply of gas to a gas dispensing system; a first sensor S1 for sensing a first parameter indicative of or related to a quantity of gas remaining in the finite source of gas from which the gas supply system is currently arranged to receive gas; a second sensor S2 for sensing a second parameter indicative of or related to a pressure of gas supplied by the gas outlet to the gas dispensing system; and a controller arranged to actuate the selector 9 to select a different source of gas dependent upon the levels and/or rate of change of the first and second parameters.