GESTRA NRG 211-1 User manual

1
EN
English
Level Electrode
NRG 211-1
Original Installation Instructions
810425-05

2
Contents
Page
Important notes
Usage for the intended purpose...............................................................................................................4
Function..................................................................................................................................................4
Safety note..............................................................................................................................................4
Directives and standards
PED (Pressure Equipment Directive) ........................................................................................................5
LV (Low Voltage) Directive and EMC (Electromagnetic Compatibility)........................................................5
ATEX (Atmosphère Explosible) .................................................................................................................5
Note on the Declaration of Conformity / Manufacturer's Declaration ...................................................5
Technical data
NRG 211-1 .............................................................................................................................................6
Scope of supply ......................................................................................................................................7
Name plate / marking ............................................................................................................................7
Installation
Dimensions NRG 211-1...........................................................................................................................8
Key .........................................................................................................................................................8
Welding standpipe...................................................................................................................................9
NRG 211-1..............................................................................................................................................9
Tools .......................................................................................................................................................9
Examples of installation ........................................................................................................................10
Key .......................................................................................................................................................10
Electrical connection
Tools .....................................................................................................................................................11
NRV 2-30 ..............................................................................................................................................12
Wiring diagram .....................................................................................................................................12
NRV 2-30, wiring connecting terminals .................................................................................................13

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Contents
Page
- continued -
Commissioning procedure
Applying supply voltage.........................................................................................................................13
Checking switching functions................................................................................................................13
Key .......................................................................................................................................................13
Troubleshooting
Indication, diagnosis and remedy ..........................................................................................................14
Checking voltage...................................................................................................................................14
Checking temperature sensor ...............................................................................................................15
Resistance values .................................................................................................................................16
Replacing electronic module .................................................................................................................16
Maintenance
Safety note............................................................................................................................................17
Checking ceramic insulator ...................................................................................................................17
Removing and disposing of the level electrode
Removing and disposing of level electrode NRG 211 .............................................................................17

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Important notes
Usage for the intended purpose
The level electrode NRG 211-1 is designed for measuring the water level in condensate lines.
In conjunction with level switch NRS 2-4 the electrode can be used as max. limit switch with high
level alarm.
Function
The level electrode together with the electronic module NRV 2-30 works according to the capacitance
measurement principle, translating the level changes into level-dependent current signals.
The electrode is self-monitoring, i. e. a fault in the insulating seal will cause a malfunction alarm.
In addition, a defined switching signal is given when the fluid reaches 395 °C because for physical
reasons the level cannot be determined exactly in this temperature range.
The level electrode works with the level switch NRS 2-4 to detect the max. limit and raise a high level
alarm. This equipment combination can be used as part of a controlled draining system in power
plants.
The electrode with welding standpipe is installed in vertical pipes.
Safety note
Danger
When loosening the electrode steam or hot water might escape!
This presents the risk of severe scalding all over the body!
It is therefore essential not to dismantle the electrode unless the boiler pressure is veri-
fied to be 0 bar.
The electrode becomes hot during operation.
Risk of severe burns to hands and arms.
Before carrying out installation and maintenance work make sure that the equipment is
cold.
Attention
The name plate specifies the technical features of the equipment. Do not commission or
operate any item of equipment that does not bear its specific name plate.
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.

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Directives and standards
ATEX (Atmosphère Explosible)
According to the European Directive 2014/34/EU the equipment must not be used in explosion-risk
areas.
Note on the Declaration of Conformity / Manufacturer's Declaration
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.
PED (Pressure Equipment Directive)
The equipment fulfils the requirements of the Pressure Equipment Directive 2014/68/EU and can be
used for fluids of group 2.
The equipment has the CE marking on the name plate.
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.

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NRG 211-1
Limiting conditions for level electrode
Material of flange/welding standpipe 1.5415 1.7380 1.4922
Admissible service pressure [barg] 320 200 320 200 320 230
[psig] 4642 2901 4642 2901 4642 3336
Admissible service temperature [°C] 120 450 120 500 120 550
[°F] 248 842 248 932 248 1022
Mechanical connection
Special flange PN 320 with welding standpipe for pipes DN ≤ 100 with tee-piece or
for pipes DN ≥ 100 with lateral bore
Material of wetted parts
Protection tube up to 500 °C 1.0305
Protection tube up to 550 °C 1.7380
Strainer 1.4571
Insulating seal of electrode Special ceramic
Flange seal 1.4541/silver
ph value
Max. admissible: 10
Temperature sensor
Pt 1000
Weight
Level electrode approx. 5.6 kg
Welding standpipe approx. 4.5 kg
Electronic module NRV 2-30
Supply voltage
12 V DC
Output
≥ 0 – ≤ 10 V DC
Enclosure
Terminal box: made of aluminium, enamel finish
Electrical connection
Six-pole connector, cable glands Pg 11
Protection
IP 54 to EN 60529
Max. admissible ambient temperature
70 °C
Technical data

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Scope of supply
NRG 211-1
1 Level electrode NRG 211-1
1 Gasket with serrated faces
1 Installation manual
Technical data
Name plate / marking
Equipment designation
Safety note
Disposal note
CE Marking
Manufacturer
Pressure rating, flanged connec-
tion, material number, protection
Fig. 1
Material number
320 bar/120°C
200 bar/450°C
T amb=70°C (158 °F)
Mat.-Nr.:
Pmax
Tmax
PN 320 DN50 1.5415 IP 54
GESTRA AG D-28215 Bremen
Betriebsanleitung beachten
See installation instructions
Voir instructions de montage
Application
range
- continued -

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Installation
Dimensions NRG 211-1
~118
~80
334.5
478
97
∅43.5
Fig. 2 7
8
6
0
9
5
3
1
2
Key
1Transit protection
2Fixing screw
3Flange
7Strainer
8Protection tube
9Temperature sensor
4Groove for gasket
5Stuffing box
6Measuring electrode
4
0Expansion bolt
aTerminal box
in electronic
module
a

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Attention
nHandle level electrode with care. Do not let if fall down.
nDo not subject electrode rod to physical shocks..
nUse only the supplied joint ring!
nUse high-temperature lubricant (e. g. Dag 156) for the expansion bolt !
nDo not lag electrode body above the hexagonal section!
nIf the the level electrode is removed for inspection work make sure it is stored in a
vertical position.
Installation
Welding standpipe
Note
nTo connect the equipment to pipes (tee-pieces) with DN ≤ 100 use full-penetration butt
welding 22 DIN 2559.
nFor larger pipes the welding standpipe can be introduced through a lateral penetration
and then be welded in place.
nThe joint ring has serrated faces and silver coated rings at both ends which must not
be removed.
NRG 211-1
1. Check seating surfaces. Clean end flange facings.
2. Insert joint ring into the groove of the welding standpipe.
3. When putting the level electrode in place make sure that the connector at the terminal box points
downwards.
4. Tighten expansion bolt 0in diagonally opposite pairs with a torque of 70 Nm .
5. Tighten expansion bolt 0in diagonally opposite pairs with a torque of130 Nm.
6. Remove the fixing screw 2of the transit protection 1.
Weld standpipe inclined upwards by at least 5° - 10° onto vertical pipe to ensure that the standpipe
can completely empty if the level falls. Make sure that the marking TOP is on top. Fig. 3.
Danger
nDuring the welding process or post weld treatment of the standpipe the temperature
of the flange seating surface must not exceed 350 °C (danger of scalding).
Tools
nOpen-end spanner A. F. 27, DIN 3110, ISO 3318
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Installation
Examples of installation
b Provided by customer
c Welding standpipe (GESTRA)
d Marking TOP
Key
d
DN ≤ 100/4"
≈12
∅63.5
≈24
∅63.5
DN > 100/4"
b
b
d
c
c
Fig. 3
- continued -
≥ 5° - 10°
5° - 10°