User manual for RTD,TC,mV/4-20mA converter module SPT-86L
0.5). The returned result is calculated accordingly to the expression:
W
=
U
n
−
U
p
×
[
Y
PH
−
Y
PL
]
[
X
PH
−
X
PL
]
×
100
Y
PL
where Y(PH), X(PH), Y(PL), X(PL) mean values of X and Y coordinates of PH i PL points.
If the normalized result exceeds the user defined characteristic values, then specific
utmost segment, defined by two next points, is used for calculations. If characteristic
from figure below is used, and if U
n
>1 then segment defined by points X(PL) =
”
90.0.
”, X(PH) = ”
100.0.
” will be used.
Fig. 6.4 Example of user defined characteristic
6.2.
EXAMPLES OF CALCULATIONS
Example 1: Selection of the permissible input range (”0-100” mode)
If in ”0-100” mode the user sets ”
InputHiRange
” = 10.0%, then permissible input voltage
range will be equal: 0÷110 mV. Upper border of the range is the result of calculations: 100 mV
+ 100 mV × 10%.
Example 2: The normalized U
n
result calculation
Let assume the input mode ”0-100” is chosen. The normalized U
n
result is calculated
accordingly to the expression on page 11. Assume that U
inp.
= 37.5 mV, this value should be
divided by the width of input range (100 mV). Finally the normalized result: U
n
= 37.5/100 =
0.375.
In case when input voltage exceeds nominal measurement range, calculations are similar. For
14
R
e
tu
rn
e
d
va
lu
e
Prąd wejściowy [mA]
0
20
40
60
80
100
Y (PH)
0
0,2
0,35
0,5
0,7
1
0,9
Y (PL)
X = „20.0.”
X = „35.0.”
X (PL) = „50.0.”
X (PH) = „70.0.”
X = „90.0.”
X = „100.0.”
Input voltage [mV]
Normalized measurement Un (for 0-100 mVrange)
5-segment characteristic
i
