USF Wallace & Tiernan DEPOLOX 4, Manual

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17.5 ENDING THE ADAPTATION SEQUENCE
The adaptation sequence may be stopped at any time using the MAN/AUTO key. The
set parameters remain unchanged.
17.5.1 ENDING OF THE ADAPTATION WITHOUT ERROR
After the loop periods (dead time Tu and raise time Ts) have been determined without
an error, calculation of the control parameters Xp and Tn starts. This is indicated by
display "Adapt 10". The calculated parameters are marked off (Xp between 1...999
% and Tn between 0.1 ... 99.9 min.) and entered into the menu. Then the chlorinator
is run to 0 % or the metering pump is switched off (display "Adapt 12"). After the
adaptation has been completed the amplifier is switched to the AUTOMATIC mode.
The loop periods are entered into the menus "Tu (min)" and "Ts (min)" for control.
If a disturbance of the control loop takes place during the adaptation period, wrong
loop takes place during the adaptation period, wrong loop periods and consequently
wrong controller parameters may be determined.
NOTE!
Carrying out the adaptation does not influence the other control parameters Ymin, Ymax
and Tp. The parameters Xp and Tn are fixed for Ymin = 0 % (no basic load of the
metering pump) and Ymax (no feedrate limitation). If the plant should require a basic
load Ymin or a feedrate limitation Ymax, it must be noted that this will limit the control
range. This involves the risk of overchlorination (Ymin too high) or underchlorination
(Ymax too much limited). The controller parameter Tp must always be adapted to the
metering pump used:
Pump strokes/min. <=20 20-40 40-80 80-125 125-200
Tp value 120 100 60 30 15
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