GEORGE FISCHER +GF+ SIGNET 2550, Инструкция по эксплуатации

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3.8 Custom K-factor calculation
K-factors can be calculated for any pipe using the
pipe id and the ft/s engineering unit options. The
procedure is based on the relationship between
the frequency output and the flow velocity:
20 ft/s = 500 Hz. therefore 1 ft/s = 25 Hz.
1. Install the 2550 in pipe according to sec 2.2.
2. Enter the pipe ID into the menu, and select
Feet per Second (FPS) as the engineering unit.
3. Establish a stable flow rate in the pipe. It is
not important to know what the rate is, just that it
be stable.
4. Read the flow rate from display and multiply
the display value (ft/s) by 25. (frequency can be
verified by monitoring TS2 if desired.)
Record the result _____ ft/s = ________Hz.
5. Change the display to read in desired engi-
neering units.
Do not change flow rate!
Record the result
_____GPM = ________Hz.
6. Divide the flow rate by the frequency result of
step 3. Record the result:
Flow Rate/Hz = A =_______________
7. K = 60 / A = _________________
23
Example illustrates calculating
a custom K-factor in GPM for
pipe with 3.068 in. id.
Unit =
ft/s
Display = 5.2 ft/s
5.2 x 25 = 130 Hz
5.2 ft/s = 130 Hz.
Unit = GPM
Display = 120 GPM
120 GPM = 130 Hz.
A = 120
÷
130 = 0.92
K = 60
÷
0.92 = 65.2