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unit in division mode, the K-factor can be entered as the scaling factor directly, and the display
would give a readout in litres per second.
Calculating a scaling factor
The scaling factor is often most easily calculated by considering the maximum input frequency
expected and by deciding what the display should read at this frequency. The scaling factor
can then be determined from the appropriate calculated result equation.
A few common examples are given below for reference:
�� is the displayed value in the desired units
��
is the measured frequency in pulses per second (Hz)
!
��
is the required scaling factor
!
Gear in RPM:
�� = ( ��
)
× ��
!
!
()
��
=
!
*
Flowmeter in litres per minute (lpm):
#
!
�� =
$
!
+
��
=
!
()
Vehicle speed e.g. km per hour, miles per hour:
�� = ( ��
)
× ��
!
!
()×()×∆-
��
=
!
*
The scaling factor range is 0.000001 to 9999999 (unsigned) or -999999 to 999999 (signed) and
it may be necessary to round off the calculated value to fit within this range. When setting
the scaling factor it is important to ensure that with the decimal point position selected, there
are enough digits to display the maximum value for the application. Otherwise, the number
of decimal places will need to be reduced or the display units altered, with the scaling factor
adjusted accordingly.
where �� is the number of teeth on the target gear.
where �� is the flowmeter K-factor in pulses per litre.
where ∆�� is the distance travelled per rotation of the target gear.
�� is the number of teeth on the target gear.
7
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