Hach SIGMA 900 - Section 5 Programming - 4-20 mA Flow Signal Calculations (Part 3); 4-20 mA Signal to Pulse Conversion Calculations

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Flow Proportional Operation
8837prg.fm
Section 5
3. Multiply Q x t x 10.
Therefore, the value entered for
INTV = _ _ _ _ CNTS is 50.
Example 5
It is desired to collect 30 samples over a 2-day period.
Average Flow Rate = 0.25 cfs (average flow rate over the 48-hour period)
Maximum Flow Rate = 1 cfs
a = 2,880 minutes
1. Calculate Q.
2. Calculate t.
3. Multiply Q x t x 10.
Therefore, the value entered for
INTV = _ _ _ _ CNTS is 240.
You will notice from the previous five examples that the average and
maximum flow rate can be expressed in any units, i.e. mgd, gpm, cfs, etc.
However, express the average and maximum flow rate in the same units for
any given situation.
0.33 mgd 15 min/sample× 10× 49.5=
Q
Average Flow Rate
Maximum Flow Rate
------------------------------------------------------
0.25 cfs
1 cfs
-------------------- - 0.25 cfs===
t
a
n
---
2,880 min
30 samples
------------------------------ - 96 min/sample== =
0.25 cfs 96 min/sample× 10× 240=