Siemens 353, Руководство пользователя

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Function Blocks UM353-1B
April 2012 3-90
3.2.89 TH_ - Track & Hold
TH_ function blocks can hold an initial value that will
transfer to the block output O1 on power up and it can be
used to track the TV input when input TC is high (1).
The HOLD value can be changed on line, using the pulser,
when the TH_.O1 block output is directly connected to X
or Y inputs in an ODC block. The range and resolution
used by the pulser making on line changes will be
determined by the X Range or Y Range inputs.
BLOCK DIAGRAM
TV
O1
O utput 1
TC
HOLD value
T rack C ommand
T rack V ariab le
INIT ial VAL ue
X03134S0
3.2.90 TOT_ - Totalizer
TOT_
function blocks accept a Boolean input and they
will retain a running total of the input transitions as the
block output as a real value for interconnection to other
blocks in the controller. The running total can be reset
when input R goes high (1). Input R is executed prior to
reading input S on each scan cycle.
Unconfigured inputs will be set to 0. When the
EDGETRIG parameter is set to 1, the total will
increment on each 0 to 1 transition on input S. When
the EDGETRIG parameter is set to 0, the total will
increment on each 1 to 0 transition.
The total will be retained during a WARM & HOT start
and will be initialized to 0.0 on a COLD start.
Input S
TOT
O1 O utput 1
TOT
TOT_
ESN = 000
S
E S N
E xec. S eq. N o.
(H)
................ 001 to 250
R T U P N I
INPUT S
(H)
..........
loop tag.block tag.output ( null )
Input R
R
S
T U
P
N
I
INPUT R
(H)
..........
loop tag.block tag.output ( null )
G D E T R G I E
EDGE TRIG
GER
(H)
......... 0-NO/1-YES 1
BLOCK DIAGRAM
S
O1
R
Totalizer
Total
Reset
Input Signal
T rack V ariable
TRACK & HOLD
INIT ial VAL ue
(S)
........................... Real (0.0)
O1 O utput 1 TRACK & HOLD
TH_
ESN = 000
TV
E S N
E xec. S eq. N o.
(H)
................ 001 to 250
L
T T U P N I
INPUT TV
(H)
.......
loop tag.block tag.output ( null )
T rack C ommand
TC
T T U P N I
INPUT TC
(H)
....... loop tag.block tag.output ( null )
A V
T
I
N I
V
C