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LRR 1-52, LRR 1-53, URB 55 - Installation & Operating Manual -
850645-01
Function
The LRR 1-52, LRR 1-53 conductivity controller is a 3-position stepping controller. It evaluates the signals
from a conductivity electrode (e.g. LRG 16-60, LRG 16-61 or LRG 17-60) or conductivity transmitter.
The conductivity controller indicates when MAX or MIN conductivity has been reached, opens or closes a
continuous blowdown valve and can actuate an intermittent blowdown valve.
Function tests and failure diagnosis can be performed using the URB 55 visual display and operating unit.
Behaviour when MIN/MAX conductivity is reached
If the minimum or maximum conductivity is reached, the appropriate output contact is opened.
What happens if the MAX limit is exceeded
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If used as a conductivity limiter, the LRR 1-52, LRR 1-53 conductivity controller does not interlock
automatically when the MAX limit is exceeded.
Possible combinations of functions and equipment
Combining the LRR 1-52, LRR 1-53 conductivity controller with the conductivity electrodes, conductivity
transmitters and URB 55 visual display and operating unit provides the following common functions:
Conductivity controller
LRR 1-52
LRR 1-53
Conductivity measurement with an LRG 1.-.. conductivity electrode and separate Pt
100 resistance thermometer (TRG 5-..)
or
Conductivity measurement with an LRG 16-9 conductivity electrode with integrated
resistance thermometer.
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Evaluating the temperature-compensated current signal of a connected
LRGT 1x-x conductivity transmitter.
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3-position stepping controller with proportional plus integral control (PI controller)
and actuation of an electrically operated continuous blowdown valve.
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MAX alarm when the conductivity limit is exceeded.
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MIN alarm when conductivity drops below the minimum limit.
Alternatively, MIN relay for automated intermittent blowdown.
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The valve position can be displayed if a potentiometer is connected (in the continuous
blowdown valve). The valve position is then shown on the URB 55 visual display and
operating unit.
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Switchable (DIP3) actual value/manipulated variable output, e.g. for remote actual value
display or direct connection to a continuous blowdown valve (manipulated variable
output)
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Volt-free input 24 V DC (standby) for inputting an external command
Control OFF / Valve CLOSED / Intermittent blowdown OFF
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Fig. 3