USF Wallace & Tiernan DEPOLOX 4, Руководство пользователя

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16.5 CONTROL PARAMETERS AND THEIR INFLUENCE ON THE
CONTROL LOOP
Xp proportional factor
With the proportional factor the controller influence (gain) is affected by a control
deviation.
Gain = (1/Xp) x 100 %
For example, Xp = 100 % signifies that a control deviation of 10 % (measuring range
1.0 mg/l, setpoint 0.50 mg/l, actual value 0.40 mg/l) is amplified by the factor 1.
With the setting Xp = 50 % the same control deviation is amplified by the factor 2.
Effect: The smaller the selection of the proportional factor Xp as a %, the greater
will be the amplification of the deviation from the setpoint and the faster the
attempt by the controller to correct the control deviation.
The gain can be changed within limits Xp = 1% (factor 100) to Xp = 999% (factor
0.1).
Tp operating cycle (only valid for metering pumps)
The operating cycle Tp defines a period in seconds which is to be adjusted to the type
of pump in question (see 12.3.2).
If an operating cycle of 30 sec. is selected, the pump starts every 30 sec. The running
time duration is dependent on the control deviation and the other set parameters. The
pump-on-time and pump-off-time always make the selected operating cycle Tp, in the
above example, 30 sec.
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