Azbil MagneW Plus+ NNK140/941, User Manual

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Appendix Azbil Corporation
Appendix-2
NNK-MagneW 3000 FLEX/PLUS Smart Electromagnetic Flowmeter Open channel Type Detector
Figure A-1 Detector size selection graph
~Note
The expression “200mm(3)” refers to the structure consisting of one 200mm
detector and two 200mm dummies. (“200mm” referts to the detector’s size
or aperture and “(3)“means that the total number of detectors including
dummy detectors.)
[How to use the graph]
The flow rate is graduated from left to right along the lower horizontal axis.
If a line is drawn perpendicular to his axis, up wards to the top of this graph
by drawing a lines directly left from the points of intersection.
[Example] Water head differential and flow velocity at flow rate of 500m
3
/hr
Draw a line upward from the point of 500mm
3
/hr, and it will intersect with
the following diagonal lines:
400mm(4), 400mm(3), 600mm(2) {=200mm(8), 400mm(1) {=200mm(4)},
200mm(3), 200mm(2) {=100mm(8)}, 200mm(1) {=100mm(4)}
When the line intersects with 200mm(2), the water head differential H1 is
found to be about 0.26m and the flow velocity per detector V(m/s) is about
2.2m/s.
Example for a maximum flow rate of 500 (m
3
/h) and weir plate width of 2
(m):