Mitsubishi Electric Q173DSCPU - Page 369

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5 OPERATION CONTROL PROGRAMS
(2) The method for output value calculation is either positive conversion (Input value:
point X, Output value: point Y) or inverse conversion (Input value: point Y, Output
value: point X) and is specified with (S1).
Each of the calculation methods is as follows.
(a) When the input value is between two points of scaling conversion data, the
output value is calculated from the nearest two points of the input value.
Positive conversion Inverse conversion
• X0  X (Input value)  XN-1
(X - X
i
)Y = Y
i
+
Y
i+1
- Y
i
X
i+1
- X
i
X
Y
(X
N-1,
Y
N-1
)
(X
0,
Y
0
)
(X
i,
Y
i
)
(X
i+1,
Y
i+1
)
Input value: X
Output
value: Y
• Y0  Y (Input value)  YN-1
X
Y
(X
N-1,
Y
N-1
)
(X
0,
Y
0
)
(X
i,
Y
i
)
(X
i+1,
Y
i+1
)
Output value: X
(Y - Y
i
)X = X
i
+
Y
i+1
- Y
i
X
i+1
- X
i
Input
value: Y
N: Number of points
(b) When the input value is other than (a), the output value is calculated from
the first or last two points of scaling conversion data.
Positive conversion Inverse conversion
• X (Input value) < X0
(X - X
0
)Y = Y
0
+
Y
1
- Y
0
X
1
- X
0
X
Y
(X
0,
Y
0
)
(X
1,
Y
1
)
Input value: X
Output value: Y
(Y < Y
0
)
• Y (Input value) < Y0
(X < X
0
)
(Y - Y
0
)X = X
0
+
Y
1
- Y
0
X
1
- X
0
X
Y
Input value: Y
Output value: X
(X
0,
Y
0
)
(X
1,
Y
1
)
• XN-1 < X (Input value)
X
Y
Input value: X
Output value: Y
(X
N-1,
Y
N-1
)
(X
N-2,
Y
N-2
)
Y = Y
N-1
+
(Y
N-1
< Y)
(X - X
N-1
)
Y
N-1
- Y
N-2
X
N-1
- X
N-2
• YN-1 < Y (Input value)
X
Y
Input value: Y
Output value: X
(X
N-1,
Y
N-1
)
(X
N-2,
Y
N-2
)
X = X
N-1
+
(X
N-1
< X)
(Y - Y
N-1
)
Y
N-1
- Y
N-2
X
N-1
- X
N-2
N: Number of points