AW Gear Meters RT-Ex15-Ex - Manual (Page 14)

AW-Lake Company 8809 Industrial Drive, Franksville, WI 53126  web: www.awgearmeters.com
 Tel: 262-884-9800  Fax: 262-884-9810  Email: [email protected]
RT-Ex15-Ex manual rev 6.13.11.docx Revision 3.3.10
14
Total Mode Programming
The Total parameters are programmed from the TOTAL A display screen. With the cover open,
use the MODE/DN button or magnetic switch to select the TOTAL A display. Press and hold
the ENT button or maintain the ENT magnetic switch. The display will first show a P in the
lower left-hand corner and will then display the first program variable for the TOTAL display
mode. Two parameters will be accessed from the TOTAL screen as follows:
TOTAL A
KFT A VALUE
ENG UNITS A
KFT A VALUE – Scaling factor to display totals in a desired engineering unit such as Gallons.
The KFT value entered here will also determine the decimal resolution of the total display. The
KFT is calculated using the K-factor of the transducer being monitored. The K-factor is the
number of impulses per engineering unit established by the transducer manufacturer or by a
calibration test. The K-factor and recommended KFT value are given on the AW-Lake
Calibration sheet.
Initial default is
10000. (Displays total pulses w/ no decimals)
The KFT factor is calculated using the following formula:
KFT= 10000/K-FACTOR
Where:
- 10000 is a constant
- K-FACTOR is the average number of pulses per desired
eng. unit that the transducer produces.
Determine the number of decimal places desired for total display, round off the result of the
formula to the desired accuracy and enter the KFT using only that number of decimal places.
Using too few decimal places can cause relatively large display errors up to several percent of
actual reading. Using too many decimal places can result in displays with a level of precision
exceeding the accuracy of the meter. It is recommended to use no more than four digits
regardless of decimal point position! The largest acceptable value for KFT is 65535 with the
decimal in any location.
For example:
A flow meter has a K-factor 2053.57 imp/Gal and the display should read in Gallons with
accuracy to three decimal places.
KFT = 10000 / 2053.7 = 4.869568 for Gallons
Round off 4.869568 to three decimal places and enter 4.870 for KFT.