Abstract
Differential pressure transmitter with orifice is widely used in process automation system. Since the most frequent problem they present is blockage in impulse line, online blockage detection method is required. The authors developed an impulse-line blockage detection algorithm, which applied to non-compressible fluids in previous works. The purpose of the paper is to apply the detection algorithm to compressible fluid such as air, which is also used in process automation systems. The experimental result shows that proposed detection algorithm is able to detect blockage before measurement of differential pressure is affected by the blockage. In addition, it is evidenced that the blockage condition when differential pressure is affected by blockage is more slight degree in air line than that in water line.
