7 Configuration
66
Functional limitations
Output level monitoring is not active in the following cases:
• Proportional band Xp = 0
• Autotuning active
• Manual mode
• Ramp function active
• Controller operating as program controller
Parameter dimensioning
Appropriate dimensioning of parameters used for determining the mean output level is required for the
output level monitoring to function correctly.
The controller differential band around the actual value defines the corrected state. It should be di-
mensioned so that it is adhered to during normal operation. The progression of the actual value can, for
example, be recorded with the startup function of the setup program. Determination of the mean output
level starts when the actual value enters the control differential band. Calculation of the mean output lev-
el starts over if there is temporary deviation from the control differential band during output level deter-
mination or if the setpoint value is changed by more than 0.5 × control differential band Δx.
A mean output level is calculated via the determination time using a moving average. The time chosen
should be long enough to ensure as accurate a calculation as possible. The determination time is fol-
lowed by a waiting period of 0.5 x reset time Tn, during which it is checked whether the actual value and
output level move within the specified limits. If one of the limits is exceeded, the calculation restarts. After
successful calculation, the output level monitoring is active.
x
y
T
C
Δy
Actual value
Output level
Determination time
Output level band
w
y
A
rt
Δx
Setpoint value
Average output level
Reset time
Controller differential band
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