Evoqua WALLACE & TIERNAN MFC, Инструкция по эксплуатации

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MFC
Functions
4.
101
Tconst Defines the constant dead time in the compound-loop-controller
loop. Consists of the sample water line dead time and the dosing
delay time (for the calculation, see 4.5.3 “Compound-Loop-
Control" on page 81).
Tvar Defines the variable dead time in the compound-loop-controller
loop. The time to be entered is based on 100 % flow rate (for the
calculation, see 4.5.3 “Compound-Loop-Control" on page 81).
Max.lin.Corr This parameter monitors changes to already learned dosing
factors.
If new dosing factor changes are learned, which are larger than the
max. linearity correction, this dosing factor is used for all values in
the dosing curve = > initialisation of the curve.
Max.lin.Corr. = 0: No curve function; only one dosing factor
for all flow rates.
Example:
Max.lin.Corr. = 50 % (based on dosing factor):
Previous dosing factor:
30 %
Newly learned dosing factor: 48 %
max. permissible correction range: 30 ± (50 % from 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 %).
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:
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