Lenze E94A - Manual (Page 554)

5 Function blocks
5.160 L_TbCompare - comparison
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Lenze · 9400 function library · Reference manual · DMS 6.7 EN · 08/2014 · TD05
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5.160.1 Function 1: dnIn1 = dnIn2
Selection: C04085 = "0"
• This function compares two signals with regard to equality. They can, for instance, provide the
comparison "actual speed equals setpoint speed " (n
act
= n
set
).
• Use the input dnTolerance to select the window within which the equality is to apply:
• Use the input dnHysteresis to select a hysteresis if the input signals are not stable and the output
oscillates.
[5-113] Function 1: Switching performance

Tip!
With this function, the FB must be used in a fast task to achieve optimum sampling of the
signals.
[5-114] Function 1: Example
TRUE
FALSE
bOut
dnTolerance dnTolerance
dnHysteresis dnHysteresis
dnIn2
dnIn1
dnIn1
dnHysteresis
dnTolerance
dnIn2
dnTolerance
dnHysteresis
TRUE
FALSE
bOut
t
t