Liquid Controls SP2800 - Manual (Page 42)

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7-2.3 Calculating the K Factor for Analog
Inputs.
Step 1. Find out what value the maximum
input signal represents. This
should be specified on your device
or with its paper work.
Example #1: 20 mA = 100 gal / min
Example #2: 5 V = 10 ft / sec
Example #3: 10 V = 32 m
3 / hr
Step 2. The Rate K Factor is equal to
10000 divided by the value from
Step 1.
Example #1:
Base K Factor = 10000
÷
100 = 100
Example #2:
Base K Factor = 10000
÷
10 = 1000
Example #3:
Base K Factor = 10000
÷
32 = 312.5
Step 3. Enter the Rate K Factor.
(See Section 3-3, Menu Item 3).
Step 4. Modify the Rate K Factor to make
the time conversion to seconds for
the count display. This is done by
dividing the Rate K Factor by the
Time Conversion Factor. If no con-
version is necessary skip this step
and let the Rate K Factor be the
same as the Count K- Factor. USE
THE TIME CONVERSION CHART
AS NEEDED.
Example #1:
Convert pounds per min to pounds per sec
Count K Factor = 100
÷
0.01666667 = 6000
Example #2: No conversion needed.
Count K Factor =1000
Example #3:
Convert gal per hr to gal per sec.
Count K Factor = 312.5
÷
0.0002778 = 1124910
Step 6. Enter the Count K Factor. (See
Section 3-3, Menu Item 3)
7-2.4 Analog K Factor Formulas.
10000 = Rate K Factor
Maximum Input Signal
Rate K Factor = Count K Factor
Time Conversion Factor
Q. Is it possible to count in one system of
measurement and display rate in another?
A. Yes, modify the Count K Factor to reflect
any units conversions. This is done by divid-
ing the Count K Factor by another Units Con-
version Factor. REFER TO THE UNITS
CONVERSION CHART AS NEEDED.
UNITS CONVERSION CHART
To convert: divide by To convert: divide by
ft to m 0.3048 kg to lb 2.2046
ft 2 to m 2 0.0929 l to ft 3 0.0353
ft 3 to m 3 0.02832 l to gal 0.2642
ft 3 to gal 7.4805 m to ft 3.2808
gal to l 3.7854 m 2 to ft 2 10.7639
gal to m 3 0.00379 m 3 to ft 3 35.3147
gal to ft 3 0.1337 m 3 to gal 264.172
gal to lb(H
2
O) 8.3378 lb to kg 0.45359