Function block library
7-82
SHB9300CRV EN 2.0
Function
The description is an example for CMP1 and is also suitable for CMP2 and CMP3.
The function of these function blocks can be set under code C0680 (CMP1). The following
comparator functions are available:
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CMP1-IN1 = CMP1-IN2
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CMP1-IN1 > CMP1-IN2
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CMP1-IN1 < CMP1-IN2
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|CMP1-IN1| = |CMP1-IN2|
l
|CMP1-IN1| > |CMP1-IN2|
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|CMP1-IN1| < |CMP1-IN2|
7.6.19.1 Function 1: CMP1-IN1 = CMP1-IN2
This function is used to find out whether two signals are identical.
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Under code C0682 you can set the window of equality.
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Under code C0681 a hysteresis can be set if the input signals are not stable and therefore the
output oscillates.
The exact function can be obtained from the line diagram.
C0682
C0682
1
0
CMP1-IN2
CMP1-IN1
C0681
C0681
CMP1-IN2
C0681
C0682
C0681
C0682
CMP1-IN1
CMP1-OUT
t
t
Fig. 7-54 Equality of signals (CMP1-IN1 = CMP1-IN2)
Example:
Thisfunctionisused toobtainthecomparison”Actualspeed is equal tosetpoint speed (n
act
=n
set
)”.