Rosemount 8732C - Page 56

Rosemount Model 8732C Integral Mount Magnetic Flowmeter System
4-10
Example
The external counter is ranged for 350 gpm. You want to set 1 pulse for
every gallon of flow. What is the maximum frequency output? (Assume
the pulse width = 0.5 ms.)
Example
Set the pulse output scaling to get the most accurate reading from the
totalizer (highest resolution). The 20 mA point = 3,000 gpm.
(Hint: Range 1000 Hz to full scale analog reading.)
Frequency
Flow Rate (gpm)
(60 s/min)(Pulse Scaling gal/pulse)
--------------------------------------------------------------------------------------
=
350 gpm
(60 s/min)(1 gal/pulse)
-------------------------------------------------------
=
5.833 Hz=
Pulse Scaling
Flow Rate (gpm)
(60 s/min)(Frequency)
------------------------------------------------------
=
3000 gpm
(60 s/min)(1000Hz)
-----------------------------------------------
=
0.05 gal/pulse=
1 Pulse 0.05 gallon=