Siemens 353, Руководство пользователя

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UM353-1B Function Blocks
April 2012 3-63
3.2.60 OR_ - OR Logic
OR_ function blocks perform a logical OR on the three
inputs. Any unused input will be set low (0).
3.2.61 ORSL - Override Selector
ORSL
function blocks are used on a one per loop basis
and they enable a primary input signal, such as the output
from a controller, to be overridden by other signals. For a
selector configured as LO, the function block outputs the
lower of the primary or override inputs. For a selector
configured as HI, the function block will output the higher
of the primary or override inputs. Override signals can be
hard limits, coming from HOLD blocks, or signals coming
from other controllers. Block override inputs 1 and 2 can
be used as HI or LO selector functions. Additional
override inputs can be accommodated by connecting these
inputs to signal selector (SEL) blocks.
When the output of the ORSL block is not the primary
input, the output OS will be high (1). In addition, the
block can cause the operator faceplate to display
‘OVERRIDE’ status when a priority level higher than 0, the default, has been selected.
If an override input is not configured the individual selector will output the other input. When no inputs are
configured, the block will output 0.0 and the OS status will be set low (0).
BLOCK DIAGRAM
A
O1 B
C
OR TRUTH TABLE
A B C O utput 1
0 0 0 0
0 0
0
0
0
0 0
0
0
1
1
1 1
1
1
1
1
1
1
1 1 1
OR
1
1
1
1
1
1
.
.
P rimary Input
OVERRIDE SELECTOR
L C S E
P
I N U P
R O
I R
SELECT or 1
(S)
......................... LO/HI (LO)
SELECT
or
2 (S)
......................... LO/HI (HI)
INPUT P
(H)
.......
loop tag.block tag.output (null)
O ver R ide PRIOR ity
(S)
....... 0,1,2,3,4,5 (0)
O1
O utput 1
OVERRIDE
ORSL ESN = 000
T P
R
P
1
2
SELECTOR
Override Input 1
OS
O verride S tatus
I
I N
N
P
P U
U T
T 1
2
INPUT 1
(H)
.......
loop tag.block tag.output (null)
INPUT 2
(H)
........
loop tag.block tag.output (null)
E S N E xec. S eq. N o.
(H)
............... 001to 250
E 1 T
2
T
C E
L E
S
Override Input 2
O
Input A
OR
O1
O utput 1 OR
OR_ ESN = 000
A
E S N E xec. S eq. N o.
(H)
................. 001 to 250
C T U P N I
INPUT B
(H)
..........
loop tag.block tag.output ( null )
Input B
B
B T U P N I
INPUT C
(H)
..........
loop tag.block tag.output ( null )
Input C C
A T U P N I
INPUT A
(H)
..........
loop tag.block tag.output ( null )
BLOCK DIAGRAM
SELECTOR
P O1
HI/ LO
1
SELECTOR
HI /LO
2
OS
1
2
O verride S tatus
O utput 1
Override Input 1
Override Input 2
.
.