GESTRA LRR 1-52, Original Installation & Operating Manual

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14 LRR 1-52, LRR 1-53, URB 55 - USA - Installation & Operating Manual -
850703-00
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 16-4, LRG 16-9) or conductivity transmitter
(LRGT 16-3, LRGT 16-4, LRGT 17-3).
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 operat-
ing unit.
What happens if 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
■
If used as a conductivity limiter, the LRR 1-52, LRR 1-53 conductivity controller does not inter-
lock 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, con-
ductivity transmitters and URB 55 visual display and operating unit enables the following common
functions to be performed:
Conductivity controller LRR 1-52 LRR 1-53
Conductivity measurement with an LRG 1.-.. conductivity electrode and sepa-
rate Pt 100 resistance thermometer
or
Conductivity measurement with an LRG 16-9 conductivity electrode with inte-
grated resistance thermometer.
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Evaluation of 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 action
(PI controller) and actuation of an electrically operated continuous blowdown
valve.
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MAX alarm when conductivity rises above the maximum limit.
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MIN alarm when conductivity drops below the minimum limit.
Alternatively, MIN relay for automatic intermittent blowdown.
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If a potentiometer is connected (in the continuous blowdown valve), the valve
position can be displayed. The valve position is then shown on the URB 55
visual display and operating unit
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Switch-selectable (DIP3) actual value/manipulated variable output, e.g., for
separate indication of the actual value 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