A filter test device comprises an inlet which communicates with a gas source, an outlet which communicates with the inlet of a filter vessel, a pneumatic valve apparatus disposed between the inlet and the outlet of the filter test device for regulating the flow of gas from the source to the filter vessel, an electronic controller for controlling the pneumatic valve apparatus in accordance with one of a plurality of sets of parameters and including a memory circuit for storing all of the sets of parameters, and a mechanism for selecting one set of parameters from all the sets of parameters stored in the memory circuit.

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