B-526-10N-E
38
11.3 Accumulated Total and Instantaneous Flowrate Calculations
(1) Total flow
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Both accumulated total and resettable total
Q = P
×
F
×
H
where P: Number of incoming pulses
F: Meter factor
H: Conversion factor
(2) Instantaneous Flowrate
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Valid only for input pulses of small periodic variation
The period of incoming pulses for the sample cycle number is measured in units of 30
μ
sec and substituted
in the following formulas for readout:
Hourly Flowrate = b1 =
3600
×
F
×
H
×
A
T
（
sec
）
Per-min. Flowrate = b2 =
b1
60
NOTE:
where A: Sample cycle number
F: Meter factor
H: Conversion factor
(3) Sample Cycle Number
It shows the number of sampling pulses in instantaneous flowrate computation. If indicated reading on the
display fluctuates, an average reading may be obtained by selecting a larger number.
If the fluctuation of indicated reading is excessive, pulsation of the flow is suspected among possible
causes and the pipeline should be inspected.
NOTE:
Sample Cycle Number
T (sec)
INPUT PULSES
If a setting A = 4 is chosen, the time is measured for 4 cycles of incoming pulses and, based on the
formulas above, calculation is made. Resolution of measurement is 30
μ
sec.
If the number of incoming pulses falls below the sample cycle number (A: Default 4) in the sampling time
(At: Default 5 sec), the instantaneous flowrate reads 0. Accordingly, if it is desired to read the instantaneous
flowrate in small flows, select a smaller sample cycle number.
Содержание ULTRA UF-II
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