Siemens 353, Руководство пользователя

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Function Blocks UM353-1B
April 2012 3-88
PRIORITIES - The priority assigned to SL PRIOR will affect the operation as follows (the outputs HS and LS will
go high with all priority assignments, including 0, when event is active):
1
. Bargraphs, event LEDs, and condition will flash. ACK button must be used to stop flashing.
2
. Bargraphs, event LEDs, and condition will flash. Flashing will stop if ACK or if event clears.
3
. Event LEDs and condition will flash. ACK button must be used to stop flashing.
4
. Event LEDs and condition will flash. Flashing will stop if ACK or event clears.
5
. Event LEDs and condition will turn on when event is active and off when the event clears.
0 . No display action occurs when event is active. The HL and LL status bits are always set to 0.
3.2.85 SRF_ - SR Flip-Flop
SRF_
function blocks perform a set dominant flip-flop
function as detailed in the truth table. An unused R input
will be set high (1) and an unused S input will be set low
(0).
POWER UP - During a warm start, when PU LAST is set
to YES, the block will initialize at the input/output states
at the instant power down occurred. A cold start will
initialize the input/output states to 0.
3.2.86 SRT_ - Square Root
SRT_
function blocks compute the square root of input
signal A. The input has a built-in low limit that will limit
the signal to the square root computation to 0.0.
BLOCK DIAGRAM
S
O1
R
SR FLIP-FLOP TRUTH TABLE
S R LO O1
1
0
0
0
X X
X 1
1
1 0
0 0 0
0
1
S - SET Input
R - RESET Input O1 - O utput
LO - Last O utput
O utput 1
S et
R eset
X (don't care)
.
.
BLOCK DIAGRAM
O1
O utput 1
LO Limit
0.0
A
A nalog Input
.
.
S et
SR FLIP-FLOP
O1
O
utput
1
SR FLIP-FLOP
SRF_ ESN = 000
S
E
E xec. S eq. N o.
(H)
................. 001 to 250
R T
U P
N I
INPUT R
(H)
..........
loop tag.block tag.output ( null )
R eset
R
S T U P N I
S N
INPUT S
(H)
..........
loop tag.block tag.output ( null )
L P U T S A
P ower U p LAST
(S)
.................. NO/YES (YES)
SQUARE ROOT
O1
O
utput
1
SQUARE ROOT
SRT_ ESN = 000
E S N
E xec. S eq. N o.
(H)
................ 001 to 250
A
INPUT A
(H)
...........
loop tag.block tag.output (null)
I T U
A
nalog Input A
P N