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NRR 2-60 - Installation & Operating Manual -
819693-00
Function
The NRR 2-60 level controller is a 3-point stepping regulator. It evaluates the data telegrams from a
level electrode (e.g. NRG 26-60 or NRG 26-61) or from a URW 60 universal converter in cycles.
In the level controller, the actual value is compared with the setpoint, and a corrective signal is formed
to compensate the control deviation. In addition, switching operations can be triggered by the output
contacts if defined switchpoints are reached.
The data are transferred to an ISO 11898 CAN bus via the CANopen protocol.
Function tests and failure diagnosis are performed using the URB 60 visual display and operating unit.
The data telegrams contain the following information:
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Level values from electrodes
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Error signals in the event of faults in electronic or mechanical parts
Behaviour in the event of MIN/MAX water level alarms
When MIN/MAX water level alarms arise, the appropriate output contact opens.
Possible combinations of functions and equipment
Combining the NRR 2-60 level controller with the level electrodes and the URB 60 visual display and operating
unit provides the following functions:
Level controller
NRR 2-60
Function
Evaluation of CAN bus data telegrams from connected
NRG 26-60 or NRG 26-61 level electrodes.
l
Evaluation of CAN bus data telegrams from the connected URW 60 universal converter
in combination with a 4-20 mA current output from a level electrode.
l
3-point stepping regulator with proportional plus integral control
(PI controller) and actuation of an electrically operated control valve.
l
MIN/MAX water level alarm.
l
Current inputs for steam and feedwater quantity
(3-component control)
l
Indication of valve position is possible if a potentiometer is connected (in the control valve). The
valve position is then shown on the URB 60 visual display and operating unit.
l
Actual value output 4-20 mA
l
Fig. 3
