Controlling fibre optic vortex shedding flowmeters.

摘要

A digital control system (10) for fibre optic vortex shedding flowmeters has a new and improved preamp circuit (26) and a computer (56) for correcting temperature, linearity and hysteresis effects. The control system (10) overcomes the inherent non-linearity of the vortex shedding phenomena and also provides two-way communication, via interfaces (66, 68), between a central control unit (the computer) and the fibre optic vortex shedding flowmeter. The improved preamp circuit (26) increases the low-end range of fibre optic vortex shedding flowmeters.