2-6 Installation and Operation 5707070-A
Advanced Energy
®
meter is not performing ideally. A point to remember is that turbulence is a non-linear
function of flow, so turbulence can create reflected signals. Interpret readings near
turbulent flows with caution.
Sources of turbulence are elbows, flanges, valves, orifices, wedges, pumps, pipe
openings, and pipe irregularities (rust, corrosion, and buildup). Always avoid vertical
pipe runs (especially downhill pipe runs).
Note: Accuracy is dependant on flow profile, and is related to the percentage of sound
reflectors and their size variation and distribution.
Figure 2-1 provides straight run examples.
Table 2-2. Flow meter distance from turbulence and reading accuracy
Upstream Downstream % Accuracy
20 diameters 10 diameters ±1% to 3% of full scale
10 diameters 5 diameters ±3% to 5% of full scale
5 diameters 2 diameters ±5% to 10% of full scale
