62
LRR 1-52, LRR 1-53, URB 55 - Installation & Operating Manual -
850645-01
Configuring the conductivity controller
Setting the control parameters
Parameter
Control deviation
Control valve
Proportional
band Pb
Pb
> higher
Large remaining deviation
Responds slowly
< lower
Small remaining deviation
Responds quickly and may open/close
continually
Example:
Measuring range 0 - 6000 µS/cm
Set point SP = 3000 µS/cm
Proportional band Pb = +/- 20 % of set point = +/- 600 µS/cm
With the measuring range and set point mentioned above, the proportional band
is then +/- 600 µS/cm or in the range 2400 µS/cm to 3600 µS/cm.
Reset time
Ti
> higher
Slow correction of deviations
Responds quickly
< lower
Fast correction of deviations, the control
loop may tend to overshoot
Responds slowly
Neutral
zone
> higher
Correction of deviations starts with a
delay
In this range, the manipulated variable
does not change.
Responds only if the control
deviation is greater than the “neutral
zone”.
< lower
Correction of deviations starts rapidly
Valve runtime
Tt
Establish the real valve runtime, e.g.
from “Closed” to “Open” (0 - 100 %).
Operating position
Specified opening of the continuous
blowdown valve. Closed during stand-
by operation.
Fig. 23
Open the control parameter
screen.
Guide to setting control parameters