Siemens SITRANS LUT400, Operating Instructions Manual

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A5E33329501 SITRANS LUT400 (HART) – OPERATING INSTRUCTIONS Page 115
mm
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H-Flume
• Sized by maximum depth of flume
• Approach is preferably rectangular, matching width and depth for distance 3 to 5
times the depth of the flume
• May be installed in channels under partial submergence (ratio of downstream level
to head). Typical errors are:
• 1% @ 30% submergence
• 3% @ 50% submergence
• For rated flows under free flow conditions, the head is measured at a point
downstream from the flume entrance. Refer to the following table.
Parameter Value
2.15.1. Primary Measuring Device (PMD)
H-Flume
2.15.4. PMD Dimensions
Flume height (D)
2.15.3.3. Maximum Head
2.15.3.4. Maximum Flow at 20 mA
2.15.3.7. Flowrate Units
2.15.3.1. Method of Flow Calculation
Ratiometric
Note: H-Flume can only be setup using ratiometric calculations
Flume Size
(Diameter in feet)
Point of Measurement
cm inches
0.5 5 1.75
0.75 7 2.75
1.0 9 3.75
1.5 14 5.5
continued on next page
Front View
Side View
point of measurement
transducer*
Plan View
flow
* The transducer must be above the maximum head by at least the blanking value (see
2.2.4. Near
Range
).
D