Simex SRP-147, Руководство пользователя

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User manual - METER SRP-147
Example 3: The linear characteristic
Let the input mode = 4-20 mA, and parameters “Lo C” and “Hi C” equal to -300 and 1200
respectively. The calculations will be done for three different input currents from example 2.
a) I
in
=10 mA and I
n
= 0,375
Accordingly to expression on page 43 for linear characteristic:
0,375 × [1200 -(- 300)]
≅
562 and next, the “Lo C” value is added to the result , so the
displayed value:
W
≅
562 + (-300) = 262
b) I
in
= 2,5 mA and I
n
= -0,0938.
W
≅
-441.
c) I
in
= 20,5 mA and I
n
= 1,0313.
W
≅
1247.
Example 4: The square characteristic
Let the input mode = 4-20 mA, and parameters “Lo C” and “Hi C” equal to -300 and 1200
respectively. The calculations will be done for there different input currents from example 2.
a) I
in
=10 mA and I
n
= 0,375
Accordingly to expression on page 43 for square characteristic: (0,375) 2 × [1200 -(- 300)]
≅
211.
and next, the
“Lo C”
value is added to the result , so the displayed value:
W
≅
211 + (-300) = -89
b) I
in
= 2,5 mA and I
n
= -0,0938.
W
≅
-287.
c) I
in
= 20,5 mA and I
n
= 1,0313.
W
≅
1295.
Example 5: The square root characteristic
Let the input mode = 4-20 mA, and parameters
“Lo C”
and
“Hi C”
equal to -300 and 1200
respectively. The calculations will be done for there different input currents from example 2.
a) I
in
=10 mA and I
n
= 0,375
Accordingly to expression on page 44 for square root characteristic:
 0,375
× [1200 -(- 300)]
≅
919.
and next, the “Lo C” value is added to the result , so the displayed value:
W
≅
919 + (-300) = 619
b) I
in
= 2,5 mA and I
n
= -0,0938 , normalized result is negative , so the displayed value is equal
to “Lo C” parameter: W
≅
“Lo C” = -300.
c) I
in
= 20,5 mA and I
n
= 1,0313.
W
≅
1223.
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