Ultrasonic flowmeter to measure the value of abnormal how to solve?

1The measured value negative display

Reason: A host and the sensor link ( on the downstream sensor, reverse ). B: is actually the reverse flow.

Solution: correct connection.

2 flow measurement and abnormal drift

Reason: A straight tube length is not enough. Around B causes fluid flow pump, valve and other disorders. C actual ripple.

Solution: A to ensure the length of the position ( 10D, 5D upstream downstream ). B installation distance maintained above 30D. C through the damping set, a corresponding increase in time.

3 Although the  water stop, measured value is not zero

Reason: A pipelined memory in the water convection B zeroing C when water flow stops, the water in a pipeline or empty state of discontent.

Solution: A B please stop completely normal in the current state to zero. C cannot keep ultrasonic propagation value, normal.

4The  measurement error

Reason: A input piping specification does not match with the actual. B old pipe scale deposition. C pipe length is not enough. D pipe in water or sediment accumulation state of discontent.

Solution: A can be inside 1% difference, about 3% of the error of measured value. B to input the correct diameter value. C will scale thickness as a lining value input. D cross-sectional area portion of reduced measurement error, resulting in increased. Moved to the vertical tube.