Siemens 353, Руководство пользователя

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UM353-1B Function Blocks
April 2012 3-23
ANALOG TREND DISPLAY
ATD
ANALOG TREND
R
A
E
TF
T rend F ull
R
R
an
G
e
P
oin
T
e
R
.........
loop tag.block tag (null)
G P T R
S M P T I M E
S a MP le TIME ....... 0.01 to 480.00 min. (0.10)
T R N D T Y P
TR e ND TYP e ..
P-P(peak/peak)/A(average)
(A)
O V E R W R I T
OVERWRIT e ......................... YES/NO (YES)
I N P U T A
I N P U T E
N
S E
INPUT A
............
loop tag.block tag.output (null)
INPUT E
............
loop tag.block tag.output (null)
E xec. S eq. N o. ................... 000 to 250 (000)
3.2.14 ASN_ - ARCSINE
ASN__
function blocks accept an input between -1.0 and 1.0 and
provide an output signal in radians of which the input is the sine.
3.2.15 ATD_ - Analog Trend Display
ATD_
blocks can be used as needed in loops (up to a
maximum of 5 per loop) to trend an analog variable
connected to input A. The block can store up to 170 data
points depending upon the use of the enable/disable
function (see below). A trend can be displayed using
Modbus commands. Data can be retrieved and displayed by
a remote operator station that can retrieve, interpret, and
display data packets from the station. A PC or i|station
running i|warePC operator interface software can display
trend data on a Loop Detail screen or Analog Detail screen.
Parameter TRND TYP allows data to be stored in one of
two formats: the average over each sample time or the
peak/peak values of the data over each sample time. All
data is stored in a normalized form based on the value of the
RG PTR (range pointer) input. The range information will
be part of the data packet when retrieved over the network
communications. When this input is unconfigured, a range
of 0.0 - 100.0 will be used.
Several inputs can control the operation of the ATD function block. Input E (enable) can be used to enable the trend
function when high (1) or unconfigured. Trend action can be disabled by setting E low (0). Each time the function
block is enabled a new trend packet will be created.
The block also includes parameter OVERWRIT that, when set to YES, will cause the block to overwrite old data
(i.e. circular file). When the parameter is set to NO, the block will stop trending when full and retain the data until
reset. When the full state is reached, output TF (Trend Full) will go high (1). This function can be used to enable a
second ATD block.
Input X
ARCSINE
O1 O utput 1
O
1
= ASIN (X)
ASN
ESN = 000
X
E
E
xec.
S
eq.
N
o. ..................... 000 to 250 (000)
X T
U
P N I
INPUT X ..............
loop tag.block tag.output ( null )
S N
BLOCK DIAGRAM
O1 X
Input X
O utput 1 .
.
ASIN (X)