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LRR 1-52, LRR 1-53, URB 55 - Installation & Operating Manual -
850645-01
Specialist terms/Abbreviations
Flushing the continuous blowdown valve
The continuous blowdown valve can be flushed automatically to prevent it from sticking. In this case, the
continuous blowdown valve is actuated at intervals (flushing interval) and opened for a certain time (flushing
time). After the flushing time, the valve moves to the position set by the control.
Operating position of the continuous blowdown valve
The operating position of the continuous blowdown valve ensures that the electrode comes into contact with
a representative amount of boiler water.
Standby mode (conductivity control)
To prevent loss of water, continuous blowdown control and automated intermittent blowdown (if enabled)
can be disabled in standby mode or when the burner is switched off. The continuous blowdown valve moves
to CLOSED position, triggered by an external control command. The MIN/MAX limits and monitoring function
remain active in standby mode.
When the equipment is back in normal mode, the continuous blowdown valve returns to the control position.
In addition, an intermittent blowdown pulse is triggered (if automated intermittent blowdown is enabled and
a blowdown interval and blowdown time have been set).
Pb (proportional band)
The proportional band enables the controller amplification to be adapted to suit the controlled system. For
further information, see page 62, guide to setting control parameters.
Ti (reset time)
The integral element ensures that control deviations can be fully corrected, with no remaining deviation.
For further information, see page 62, guide to setting control parameters.
Neutral zone
If the actual value reaches the (set point +/- of the neutral zone), the manipulated variable does
not change in this range, see page 62.
PI controller
Controller with proportional (P) and integral (I) control.
LRR .. / LRG .. / LRGT .. / URB ..
GESTRA equipment and type designations, see page 10.
SELV
Safety Extra Low Voltage