α
2 Simple Application Controllers
Function Blocks 6
6 - 69
6.25
Subtraction Block
The function block is used to subtract inputs B from A hence produce the resultant Y.
Table 6.33: Subtraction Function Block
Setup of the Subtraction Function Block directly from the
α
2
Series Controller
1 ) Allocate the input pin to be used for the function block.
2 ) Press the “OK” key with the cursor in the function block. The function block edit screen is
displayed as shown.
3 ) Press the “OK” Key and enter the function block settings using the “ and ” keys. The
Subtraction operation y=A-B must be specified.
4 ) Using the “ and ” keys highlight Constant A and press the “OK” key to enter either a
Directset, Analog In or FB Value.
5 ) Repeat step 4 for Constant B and return to the FBd using the “ESC” key.
Function
Set Item
Description
I
Input pin for subtraction function block
FB
This function block operates the expression Y=A-B.
The value of Y,A and B is in the range: -32768 to 32767
a) A,B
- Constant value (Setting range:-32768 to 32767
- Analog value
- FB value
Output
1) Word Output
When the input pin is ON, Y=A-B is executed and the word output will
be given the result. When the input pin is OFF the expression is not
executed and the Y value will retain the last result.
2) Bit Output
- Operation result Y<-32768: Output pin turned ON and the operation
result Y will be set to -32768
- Operation result Y>32767: Output pin turned ON and the operation
result Y will be set to 32767
0
0
0
U
S
O
I
B
P
B 0 0 1 : S
C h a n g e N o
D e l e t e
F B
B
U
S e t u p
F B
O u t p u t
a
V
l
y = A - B
0
B 0 0 1 : S B
U
D i r e c t S e t
A n a l o g
I n
F B V a l u e
B 0 0 1 : S B
U
