Siemens LOGO!, Manual

Page: 216 / 534

LOGO! functions
4.4 Special functions list - SF
LOGO!
216
Manual, 04/2011, A5E03556174-01
4.4.19 Analog differential trigger
Short description
The output is set and reset depending on a configurable threshold and a differential value.
Symbol in LOGO! Wiring Description
Input Ax Input Ax is one of the following analog signals:
• AI1 to AI8 (*)
•
AM1 to AM6 (if 0BA6) or AM1 to AM16 (if 0BA7)
• NAI1 to NAI32 (if 0BA7)
•
AQ1 to AQ2
• NAQ1 to NAQ16 (if 0BA7)
•
Block number of a function with analog output
Parameter A: Gain
Range of values: ±10.00
B: Zero offset
Range of values: ±10,000
On: On/Off threshold
Range of values: ±20,000
Δ: Differential value for calculating the off parameter
Range of values: ±20,000
p: Number of decimals
Range of values: 0, 1, 2, 3
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Output Q Q is set or reset, depending on the threshold and
difference values.
* AI1...AI8: 0...10 V corresponds with 0...1000 (internal value).
Gain and offset parameters
Please note the information on gain and offset parameters in topic "Calculating the gain and
offset of analog values (Page 154)".
Parameter p (number of decimals)
Applies only to the display of On, Off and Ax values in a message text.
Timing diagram A: Function with negative difference Δ
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