Simex SRP-147, Руководство пользователя

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User manual - METER SRP-147
Volume of tank can be write by general formula:
V
=
∫
P
p
⋅
dh
Possible combination of tank shape for calculation the volume:
cylindrical
tank in
vertical
position
cylindrical
tank in
horizontal
position
parameter
s setting
(for vertical
and
horizontal
position of
tank)
t h2=0
t h3=0
t h3=0 t h2=0 t h1=0
t h3=0
- t h1=0 t h1=0
t h2=0
10.2. EXAMPLES OF CALCULATIONS
Example 1: Selection of the permissible input range (“4-20” mode)
If in “ 4-20 ” mode the user sets “Lo r” = 20,0% and “Hi r” = 10,0%, then permissible
input currents range will be equal: 3,2 mA ÷ 22 mA. Lower border of the range is the result of
calculations: 4 mA - 4 mA × 20%, and the higher : 20 mA + 20 mA × 10%.
Example 2: The normalized I
n
result calculation
Let the input mode = 4-20 mA. The normalized I
n
result is calculated accordingly to the
expression on page 42, so if I
in
= 10 mA then 10 mA - 4 mA = 6 mA, and this result should be
divided by the width of input range (16 mA). Finally the normalized result: I
n
= 6/16 = 0,375.
In case when input current exceeds nominal measurement range, calculations are similar. For
example if input current is equal 2,5 mA then I
n
= (2,5 - 4)/16
≅
-0,0938, and if input current is
equal 20,5 mA then I
n
= (20,5 - 4)/16
≅
1,0313.
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