Abstract: A medical infusion testing device has a pair of identical measuring tubes with valves to direct flow to one tube while draining the one tube down to a predetermined level. The level of liquid in the tubes is measured by an optical charge coupled device. A logic device is arranged to measure a spot reading over a small flow or an averaged flow over an entire reading.

Abstract: A flow measuring device for checking on medical infusion devices comprises a vertical tube 5 having at least three level sensers 10 and 11 for sensing when a liquid reaches the level of each senser. A logic unit 12 containing a timing device triggered by the first senser measures the time taken for the liquid to reach the second senser and the logic unit compares this time with a predetermined time and if the time is less than the predetermined time sets the device to compare a time taken to reach the third senser but if the time is more than the predetermimed time calculates the flow rate. A multiway valve 1 at the inlet of the device under the control of the logic unit permits flow from the infusion device under test to the tube, from the device under test to a drain 15 or to that drain and the tube, or from the tube to the drain or blocks all flows.