Lenze 8400 - Manual (Page 1196)

18 Function library
18.1 Function blocks | L_ComparePhi_1
1196
Lenze · 8400 protec HighLine · Reference manual · DMS 3.0 EN · 03/2013 · TD05
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18.1.28.3 Function 3: dnIn1 < dnIn2
This function serves, for instance, to implement the comparison "actual speed is lower than a limit
value" (n
act
< n
x
) for one direction of rotation.
[18-16] Function 3: Switching performance
Functional sequence
1. If the value at dnIn1_p falls below the value at dnIn2_p, bOut changes from FALSE to TRUE.
2. Only if the signal at dnIn1_p exceeds the value of dnIn2_p - hysteresis again, bOut changes back
from TRUE to FALSE.
[18-17] Function 3: Example
 C001671 : Hysteresis
TRUE
FALSE
bOut
dnIn2_p
dnIn1_p
Œ
 C001671 : Hysteresis
dnIn1_p
dnIn2_p
TRUE
FALSE
bOut
t
t
Œ