GESTRA NRR 2-52 User manual

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EN
English
Level Controller NRR 2-52
Level Controller NRR 2-53
Operating & Display Unit URB 50
NRR 2-52
NRR 2-53
URB 50
Original Installation Instructions
819222-03

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Contents
Page
Important notes
Usage for the intended purpose...............................................................................................................5
Function..................................................................................................................................................5
Safety note..............................................................................................................................................6
Directives and standards
VdTÜV Bulletin "Wasserstand 100" (= Water Level 100)..........................................................................6
LV (Low Voltage) Directive and EMC (Electromagnetic Compatibility)........................................................6
ATEX (Atmosphère Explosible) .................................................................................................................6
UL/cUL (CSA) Approval ............................................................................................................................6
Note on the Declaration of Conformity / Declaration by the Manufacturer ........................................6
Technical data
NRR 2-52, NRR 2-53...............................................................................................................................7
Scope of supply ......................................................................................................................................9
In control cabinet: Mounting level controller
Dimensions NRR 2-52, NRR 2-53..........................................................................................................10
Key .......................................................................................................................................................10
Installation in control cabinet.................................................................................................................10
Name plate / marking ...........................................................................................................................11
In control cabinet: Installing the operating & display unit
Dimensions URB 50 ..............................................................................................................................12
Key .......................................................................................................................................................12
Installation in control cabinet.................................................................................................................12
Name plate / marking ...........................................................................................................................12
In control cabinet: Wiring level controller
Wiring diagram for level controller NRR 2-52.........................................................................................13
Key .......................................................................................................................................................13
Wiring diagram for level controller NRR 2-53.........................................................................................14
Key .......................................................................................................................................................14
In control cabinet: Wiring the operating & display unit
Back of equipment, position of connector..............................................................................................15
Connection of supply voltage.................................................................................................................15
Pin assignment for data line NRR 2-52, NRR 2-53 - URB 50 .................................................................15
Key .......................................................................................................................................................15

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Contents - continued -
Page
In control cabinet: Wiring the level controller / the operating & display unit
Connection of supply voltage.................................................................................................................16
Connecting output contacts...................................................................................................................16
Connecting level electrode, level transmitter .........................................................................................16
Connection of data line for the level controller / operating & display unit ...............................................16
Connecting the potentiometer (for indication of valve positions), connections IN ../ OUT / 4-20 mA........16
In the plant:
Wiring level electrode / level transmitter
Connecting level electrode, level transmitter .........................................................................................17
Level controller: Factory settings
Level controller NRR 2-52, NRR 2-53 ....................................................................................................17
Level controller: Changing factory settings
Changing function and input for level electrode/transmitter...................................................................18
Tools.....................................................................................................................................................19
Before putting the level control system into operation
Establishing measuring range ...............................................................................................................20
Operating & display unit URB 50
User interface .......................................................................................................................................21
Key .......................................................................................................................................................21
Switch on supply voltage.......................................................................................................................21
Explanation of icons ..............................................................................................................................22
Commissioning procedure
Adjusting the MIN/MAX switchpoints and setpoint .................................................................................24
Numberpad...........................................................................................................................................24
Key .......................................................................................................................................................24
Establishing measuring range for level electrode NRG 2.-......................................................................25
Setting the control parameters ..............................................................................................................26
Additional information on control parameter settings.............................................................................26
Key .......................................................................................................................................................26
Setting the control parameters for 3-element control (optional) .............................................................27
Key .......................................................................................................................................................27
Only NRR 2-52: Calibrating the potentiometer for indication of valve position ........................................28

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Contents - continued -
Page
Operation
Manual actuation of control valve..........................................................................................................28
Trending................................................................................................................................................29
Key .......................................................................................................................................................29
Testing MIN/MAX alarm, entering date and time ...................................................................................30
Setting up a password and logging in ..................................................................................................31
Key .......................................................................................................................................................31
Log out .................................................................................................................................................33
Alarm & malfunction list........................................................................................................................34
Key .......................................................................................................................................................34
Error, alarm and warning messages
Indication, diagnosis and remedy ..........................................................................................................35
Further Notes
Action against high frequency interference............................................................................................36
Decommissioning / replacing the level controller NRR 2-5.....................................................................36
Decommissioning / replacing the operating & display unit URB 50 ........................................................36
Disposal................................................................................................................................................36

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Important notes
Usage for the intended purpose
The functional unit consisting of the operating & display unit URB 50 and the level controller NRR 2-52 /
NRR 2-53 in conjunction with level electrodes NRG 2.-.. or level transmitter NRGT 26-1 is used as water
level controller and as limit switch, for instance in steam boilers, (pressurized) hot-water installations as
well as condensate and feedwater tanks.
The functional unit consisting of the URB 50 and the level controller NRR 2-5.. is designed for use with
level electrodes NRG 21-.. or NRG 26-21 as well as level transmitter NRGT 26-1.
The operating & display unit URB 50 and the level controller NRR 2-52, NRR 2-53 form a functional
unit featuring the following properties:
Level Controller NRR 2-52 NRR 2-53
Evaluation of the voltage signal of the level electrode NRG 2-.. and standardized
measuring range X X
Evaluation of current signal of level transmitter NRGT 26-1 X X
3-position stepping controller with proportional-plus-integral control action
(PI controller) and control of an electrically actuated control valve X
Continuous controller as PI controller for the control of an electro-pneumatically
operated control valve X
Indication of MIN / MAX water level limit X X
Current inputs for steam and feedwater flowrate (3-element control) (optional) X X
Indication of valve position if control valve is provided with a potentiometer X
Actual value output 4-20 mA (optional) X X
Operating & display unit URB 50
Indication of actual value (indicated in percent and as bar graph) X
Indication of valve position (indicated in percent and as bar graph) X
Standardized measuring range if level electrode NRG 2.-.. is connected X
Indication/adjustment of control parameters X
Standardization and evaluation of current inputs for steam and feedwater flowrate (3-element
control) (optional) X
Trend record X
Indication and listing of errors, alarms and warnings X
Test of MIN / MAX output relays X
Manual/automatic operation X
Password protection X
Function

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Important Notes - continued -
Safety note
The equipment must only be installed, wired and commissioned by qualified and competent staff.
Retrofitting and maintenance work must only be performed by qualified staff who - through adequate
training - have achieved a recognised level of competence.
Danger
The terminal strips of the equipment are live during operation.
This presents the danger of electric shock!
Always cut off power supply to the equipment before mounting, removing or
connecting the terminal strips!
Attention
The name plate specifies the technical features of the equipment. Note that any piece of
equipment without its specific name plate must neither be commissioned nor operated.
Directives and standards
VdTÜV Bulletin "Wasserstand 100" (= Water Level 100)
The functional unit consisting of the operating & display unit URB 50 / level controller NRR 2-52, NRR
2-53 in conjunction with level electrode NRG 2.-.. and level transmitter NRGT 26.-.. is type approved
according to VdTÜV Bulletin "Wasserüberwachung (= Water Monitoring) 100".
The VdTÜV Bulletin "Wasserstand (= Water Level) 100" specifies the requirements made on water level
control and limiting equipment for boilers.
ATEX (Atmosphère Explosible)
According to the European Directive 2014/34/EU the equipment must not be used in explosion risk areas.
LV (Low Voltage) Directive and EMC (Electromagnetic Compatibility)
The equipment meets the requirements of the Low Voltage Directive 2014/35/EU and the EMC
Directive 2014/30/EU.
Note on the Declaration of Conformity / Declaration by the Manufacturer
For details on the conformity of our equipment according to the European Directives see our Declaration
of Conformity or our Declaration of Manufacturer.
The current Declaration of Conformity / Declaration of Manufacturer are available in the Internet under
www.gestra.com/documents or can be requested from us.
UL/cUL (CSA) Approval
The equipment meets the requirements of Directives: UL 508 and CSA C22.2 No. 14-13, Standards for
Industrial Control Equipment. File E243189.

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NRR 2-52, NRR 2-53
Supply voltage
24 VDC +/– 20%
Fuse
external 0.5 A (semi-delay)
Power consumption
5 VA
Connection of level electrode / level transmitter (switch-selectable)
1 input for level electrode NRG 21-.. or NRG 26-21, with 3 poles and screen or
1 analogue input 4-20 mA, e. g. for level transmitter NRGT 26-1, with 2 poles and screen
Supply voltage of level electrode
12 VDC
Input/output
Interface for data exchange with operating & display unit URB 50
Inputs
1 analogue input potentiometer 0 - 1000 Ω, two-wire connection
(indication of valve position, only NRR 2-52)
1 analogue input 4-20 mA (steam flowrate) (optional)
1 analogue input 4-20 mA (feedwater flowrate) (optional)
Outputs
NRR 2-52: 2 volt-free change-over contacts,
8 A 250 V AC / 30 V DC cos ϕ= 1 (control valve).
2 volt-free change-over contacts,
8 A 250 V AC / 30 V DC cos ϕ= 1,
De-energizing delay: 3 seconds (MIN/MAX alarm).
NRR 2-53: 4 volt-free change-over contacts, 8 A 250 V AC / 30 V DC cos ϕ= 1,
De-energizing delay: 3 seconds (MIN 1, MIN 2 / MAX 1, MAX 2 alarm)
1 analogue output 4-20 mA, max. load 500 ohm (manipulated variable Y).
Provide inductive loads with RC combinations according to manufacturer's specification to ensure
interference suppression
NRR 2-52, NRR 2-53: 1 analogue output 4-20 mA, max. load 500 ohm (e. g. for actual value indication)
(optional)
Indicators and adjustors
1 tri-colour LED indicator (start-up = amber, power ON = green, malfunction = red)
1 code switch with four poles for configuration
Housing
Housing material: base: polycarbonate, black; front: polycarbonate, grey
Conductor size: 1 x 4,0 mm² solid per wire or
1 x 2.5 mm2per stranded wire with sleeve to DIN 46228 or
2 x 1.5 mm2per stranded wire with sleeve to DIN 46228 (min. ∅ 0.1 mm)
terminal strips can be detached separately
Fixing of housing: Mounting clip on supporting rail TH 35, EN 60715
Electrical safety
Pollution degree 2 for installation in control cabinet with protection IP 54, completely insulated
Protection
Housing: IP 40 to EN 60529
Terminal strip: IP 20 to EN 60529
Technical data

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NRR 2-52, NRR 2-53 - continued -
Weight
approx. 0.5 kg
Ambient temperature
when system is switched on: 0° ... 55 °C,
during operation: –10 ... 55°C,
Transport temperature
–20 ... +80 °C (<100 hours), defrosting time of the de-energized equipment before it can be put into
operation: 24 hours.
Storage temperature
–20 ... +70 °C, defrosting time of the de-energized equipment before it can be put into operation:
24 hours.
Relative humidity
max. 95%, no moisture condensation
Approvals:
TÜV certificate VdTÜV Bulletin "Water Lever 100" (= Water Level 100):
Requirements made on water level limiting & control equipment.
Type approval no. TÜV · WR · XX-427
(see name plate).
UL/cUL (CSA) Approval UL 508 and CSA C22.2 No. 14-13, Standards for Industrial
Control Equipment. File E243189.
Technical data - continued -
URB 50
Supply voltage
24 VDC +/– 20%
Fuse
internal automatic
Power consumption
8 VA
Input / output
Interface for data exchange.
User interface
Analogue resistive touch screen, resolution 480 x 271 pixels, illuminated.
Dimensions
Front panel: 147x107 mm
Panel cut-out: 136x96 mm
Depth: 56 + 4 mm
Electrical connection
1 connector with 3 poles,
1 D-SUB connector with 9 poles.

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URB 50 - continued -
Technical data - continued -
Scope of supply
NRR 2-52
1 Level controller NRR 2-52
1 Installation manual
NRR 2-53
1 Level controller NRR 2-53
1 Installation manual
URB 50
1 Operating & display unit URB 50
1 Data line L = 5 m
Protection
Front panel: IP 65 to EN 60529
Back: IP 20 to EN 60529
Weight
approx. 1.0 kg
Ambient temperature
when system is switched on: 0 ° ... 55 °C,
during operation: –10 ... 55 °C
Transport temperature
–20 ... +80 °C (<100 hours), defrosting time of the de-energized equipment before it can be put into
operation: 24 hours.
Storage temperature
–20 ... +70 °C, defrosting time of the de-energized equipment before it can be put into operation:
24 hours.
Relative humidity
5 - 85 %, no moisture condensation

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In control cabinet: Mounting level controller
Dimensions NRR 2-52, NRR 2-53
Fig. 1
1Upper terminal strip
2Lower terminal strip
Key
Installation in control cabinet
The level controller NRR 2-52, NRR 2-53 is clipped onto the support rail type TH 35, EN 60715 in the
control cabinet. Fig. 1 4
3 Housing
4 Supporting rail type TH 35, EN 60715
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2
100
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120