The Fixed Volume Sample System (TS13, MDFV) is designed to take a specified amount of sample. It can be used in both low and high pressure applications. A fixed amount of sample is isolated from the process, then low-pressure nitrogen (or available motive force) is used to blow the sample down into the sample container. Process Needle Purge removes any residual sample. The entire operation of the TSI3 is performed with a single valve.