Siemens 353, Руководство пользователя

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UM353-1B Function Blocks
April 2012 3-49
3.2.49 MTH_ - Math
MTH_ function blocks provide universal arithmetic
capability. As shown in the block diagram, each input has
gain and bias scaling. The resulting signals are then applied
to configurable math operations (DIV, MUL, ADD and
SUB). Operation A will be performed first on inputs A and
B. Operation B will be performed next on the resultant and
input C.
Unused inputs to a MUL or DIV operation will be set to 1.0
and those to an ADD or SUB operation will be set equal to
0.0. The operation of those inputs will function normally
so it is important to insure that the bias and gain settings are
set properly.
In a DIV operation, when a divisor is 0.0 the output will go
to the maximum Real number with the sign determined by
the numerator. If the numerator is 0 the output will be 0.
O1
A
C
BLOCK DIAGRAM
O utput 1
IN put A
MATH
BIAS
IN put B
GAIN
IN put C
GAIN
+
+
+
IN put A
GAIN
IN put B
BIAS
IN
put
C
BIAS
OP eration A
Add, Sub, Mul, Div
OP eration B
Add, Sub, Mul, Div
OUT put
GAIN
+
OUT
put
BIAS
B
I nput C
I nput B
I nput A
+
+
+ + +
.
.
Rev2
Input A
MATH
N
OUT put GAIN
(S)
....................................... Real
(1.0)
O1
O
utput
1
ADD, SUB, MUL, DIV
MTH_ ESN = 000
I A
A
B
C
MATH
Input B
Input
C
INPUT C
(H)
...................... loop tag.block tag.output
(null)
E xec. S eq. N o.
(H)
............................ 001 to 250
I
I
I N
N
N P
P
P U
U
U T
T
T A
B
S E N
INPUT B
(H)
......................
loop tag.block tag.output (null)
INPUT A
(H)
...................... loop tag.block tag.output
(null)
OP eration A
(S)
...................... Add,Sub,Mul,Div
(Add)
C
G T U O
N I A G A N I
N I A G B N I
N I A G C N I
S I A B T U O
A N I
B N I
C N I
S I A B
S I A B
S I A B
A O P
B O P
IN put C GAIN
(S)
....................................... Real
(1.0)
IN
put
B GAIN
(S)
....................................... Real
(1.0)
IN put A GAIN
(S)
....................................... Real
(1.0)
OUT put BIAS
(S)
....................................... Real
(0.0)
IN put C BIAS
(S)
....................................... Real
(0.0)
IN put B BIAS
(S)
....................................... Real
(0.0)
IN put A BIAS
(S)
....................................... Real
(0.0)
OP
eration
B
(S)
...................... Add,Sub,Mul,Div
(Add)