Siemens 353, Руководство пользователя

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UM353-1B Function Blocks
April 2012 3-33
1. oncE will write once to the START CL (Modbus Starting Coil. The controller will write when any block input
value changes state.
2. P2P will update at the controller peer to peer rate set in the ETHERNET block.
3. Ct will update at the cycle time of the controller.
The Ct option is normally only used when writing time critical changes. Input T can be used to trigger a write. This
would be used in cases where the oncE option has been selected, input values do not change, and there may be a
concern that the receiving device has lost the values.
Output QS indicates the quality of the write operation and will go high (1) when the write is not completed
successfully. This is normally associated with failure of the destination device to receive data due to a
communication failure or a misconfiguration of the device.
3.2.26 DAM_ - Deviation Amplifier
DAM_
function blocks compute the difference between
inputs A and B, amplify the difference signal, and sum the
resultant with an internal BIAS and an external signal at
input C. Unused inputs are set to 0.0.
BLOCK DIAGRAM
A
O utput 1
-
GAIN
+
O1
BIAS
Input A
Input B
Input C
B
C
+
+
+
O1 = GAIN x (A - B) + BIAS + C
.
.
Input A
DEVIATION AMPLIFIER
N G
I N U C
GAIN
(S)
.................................... Real (1.0)
BIAS
(S)
..................................... Real (0.0)
INPUT C
(H)
..... loop tag.block tag.output (null)
O1` O utput 1
DEVIATION
DAM_ ESN = 000
I A
T P
A
B A I S
E S N
E
xec.
S
eq.
N
o.
(H)
............ 001 to 250
AMPLIFIER
Input B B
Input C
C
I N U
A T
P
I N U B T P
INPUT B
(H)
.....
loop tag.block tag.output (null)
INPUT A
(H)
.....
loop tag.block tag.output (null)