Liquid Controls SCAMP - Manual (Page 18)

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APPENDIX C: CALCULATING THE K-FACTOR FOR YOUR METER
STEP 1: Determine how many whole pulses per unit of measure per output channel are
desired for the application.
Discussion: If the output counter only counts one channel on one edge (whether rising or
falling), then the number desired is usually 1, 10, 100, or 1000 pulses per unit of volume.
If, however, the counter uses both channels (e.g. dispensers usually count on both
channels and on both edges) the number of whole pulses per unit of measure is the
number of edges divided by 4. Dispensers generally require 250 whole pulses per
gallon, which is 1000 edges divided by 4.
STEP 2: Determine the nominal number of pulse edges per unit of volume that the raw
pulser will output for your meter (refer to Meter Calibration Sheet).
Discussion: The LC 100-ppr POD pulser outputs 100 whole pulses per channel times
two channels, times two edges per channel or 400 pulse edges per revolution. Multiply
this by the revolutions per flow unit for your meter. For example, an M7 meter has a
nominal displacement of 5.555 revolutions per gallon. Therefore, the nominal number of
pulse edges per unit is 2222 edges/gallon.
Set the initial SCAMP k-Factor in Function 0 using the following number.
Initial k-Factor =
Input nominal pulse edges per unit volume
Output whole pulses per unit volume
The range of allowable k-Factors is 4.000 to 9999.
Examples:
1. An M7 meter is to be set to output 100 pulses per gallon into a single channel
counter.
Initial k-Factor = 2222 edges / gallon (nominal) = 22.22
100 pulses / gallon
Switch setting is dialed to 22222 (2222 with two decimal places). Put
function switch in function 0 and enter the value by pressing the Data
Entry pushbutton. The display will scroll “F22.22”.