General Instructions - Global Water FP101 User Manual

Congratulations on your purchase of a Global FP101 or FP201 Flow Probe!
Our Flow Probe has been field-tested in several hundreds of locations throughout the world. Our customers
praise the product's ease-of-use, accuracy, durability, portability, and reasonable cost. Please follow the sim-
ple procedures for operation presented in this manual and you will be accurately and reliably monitoring real-
time flow in no time.
1) Make sure the Flow Probe's propeller turns freely by blowing strongly on the prop.
2) Point the propeller directly into the flow you wish to measure. Face the arrow inside the prop housing
downstream. The FP101 probe handle is a two piece rod expandable from 3' to 6', and the FP201 is a
three section rod expandable from 5' to 15'. To expand the rod for correct placement in flow, loosen the
locking nut on the handle, pulling out the top piece and retightening the nut.
3) Scroll with the right button until the "V" for velocity appears on the left hand of the screen. The top num-
ber in "V" mode is the instantaneous velocity to the nearest 0.1 ft/sec. Push the left button to toggle the
bottom number between maximum ("mx") and average ("av") velocities to the nearest 0.01 ft/sec.
4) With the propeller placed at your measuring point, push both the right and left buttons simultaneously and
release to clear the computer and reset the average and maximum velocities. Hold the probe in place for
several seconds until the average velocity reading steadies and then remove the probe. The average
velocity will freeze once the propeller stops turning. See Average Velocity section for more information on
obtaining average velocities.
5) Measure/calculate the cross-sectional area of your flow stream in square feet. If you are measuring flow in
round pipes, measure the depth of water and use the enclosed tables to determine cross-sectional area
(see Calculations section). If you are measuring flow in another channel type, manually measure water
depth at several points across the flow. These measurements are most easily recorded by drawing a dia-
gram on graph paper with a scale of 1 square foot per graph paper square. Cross-sectional area (in
square feet) can then be found by counting the number of squares in the stream.
6) The average velocity (calculated with the Flow Probe in feet/second) times the cross-sectional area
(square feet) equals flow in cubic feet per second (cfs), or Q = V x A.
7) If the propeller gets fouled while measuring flow, clean it until the prop turns freely and start over.
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G G e e n n e e r r a a l l I I n n s s t t r r u u c c t t i i o o n n s s
FP101/FP201 - 1
Global Water Instrumentation, Inc.