Evoqua WALLACE & TIERNAN SFC, Оригинальное руководство пользователя

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88
WT.050.590.000.DE.IM.0719
Functions
SFC
4.
Special case:
Example:
Control factor
Setting the ratio of control range and measuring range, in order to
adjust the control amplification Xp to the process.
Control factor=
(End of measuring range - start of measuring range): Control
range
Example:
PI shutdown
Defines a range for flow rate changes triggered by the YPI stop
function when the limit is exceeded. Factory setting = 5%, i.e. if the
change in flow rate is greater than 5% the PI controller is frozen for
a specific length of time. Adjustment range 5 to 100 %.
Max.lin.Corr. = 0: The curve function is turned off, only one
dosing factor is valid for all flow rates and
the higher-level single feedback closed loop
control remains active.
Max.lin.Corr. = 50 % (based on dosing factor):
Previous dosing factor: 30 %
Newly learned dosing
factor: 48 %
max. permissible
correction range: 30 ± (50 % von 30 %) = 30 % ± 15 %
Change in this case: 48 % - 30 % = +18 %
=> The new dosing factor is assumed for the entire curve,
because the new dosing factor (+ 48%) is greater than the
max.lin.Correction (+18%).
Start of measuring
range: pH 4
End of measuring
range: pH 9
Max. process control
range: ± 1 pH (=> 2 pH increments)=> Control
factor = (9 - 4) : 2 = 2,5