GESTRA NRG 10-52 User manual

Level Electrode
NRG 10-52
NRG 16-52
Original Installation &
Operating Manual
850696-00
EN (USA)
English

2NRG 10-52, NRG 16-52 - USA - Installation & Operating Manual - 850696-00
Contents
Content of this Manual......................................................................................................................... 4
Scope of supply, product package....................................................................................................... 4
How to use this Manual........................................................................................................................ 5
Illustrations and symbols used............................................................................................................ 5
Hazard symbols in this Manual............................................................................................................ 5
Types of warning .................................................................................................................................. 6
Specialist terms, abbreviations ........................................................................................................... 7
Usage for the intended purpose........................................................................................................... 8
Applicable directives and standards.............................................................................................. 8
Improper use ........................................................................................................................................ 8
Basic safety information ...................................................................................................................... 9
Required personnel qualifications..................................................................................................... 10
Notes on product liability................................................................................................................... 10
Function .............................................................................................................................................. 11
Technical data .................................................................................................................................... 12
Rating plate, identification................................................................................................................. 12
Overall view ........................................................................................................................................ 13
Dimensions ......................................................................................................................................... 14
Preparing for installation ................................................................................................................... 15
Installation.......................................................................................................................................... 16
Installing the NRG 10-52, NRG 16-52, step 1 ................................................................................. 17
Functions table .............................................................................................................................. 17
Installing the NRG 10-52, NRG 16-52, step 2 ................................................................................. 18
Installation example with dimensions............................................................................................... 19
Electrical connection.......................................................................................................................... 21
Five-pole connector of the NRG 10-52, NRG 16-52 ........................................................................ 21
Connecting the level electrode....................................................................................................... 22
Assigning the five-pole connector of the NRG 10-52, NRG 16-52 ................................................... 22
Terminals in the contact block ....................................................................................................... 22

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NRG 10-52, NRG 16-52 - USA - Installation & Operating Manual - 850696-00
Contents
Bringing into service, fault indications and troubleshooting ........................................................... 23
Taking out of service.......................................................................................................................... 23
Disposal .............................................................................................................................................. 24
Returning decontaminated equipment.............................................................................................. 24
UL components................................................................................................................................... 24

4NRG 10-52, NRG 16-52 - USA - Installation & Operating Manual - 850696-00
Content of this Manual
Product:
■ Level Electrode NRG 10-52, NRG 16-52
First edition:
BAN 850696-00/08-2021cm
© Copyright
All rights reserved. Any misuse, particularly reproduction and dissemination to third parties, is not
permitted. The General Terms & Conditions of GESTRA AG apply.
Scope of supply, product package
NRG 10-52
1 Level electrode NRG 10-52
1 Installation & Operating Manual
NRG 16-52
1 Level electrode NRG 16-52
1 Installation & Operating Manual

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NRG 10-52, NRG 16-52 - USA - Installation & Operating Manual - 850696-00
How to use this Manual
This Installation & Operating Manual describes the correct use of NRG 10-52, NRG 16-52 level
electrodes. It applies to persons who integrate this equipment in control systems, install, bring
into service, operate, maintain and dispose of this equipment. Anyone carrying out the above-
mentioned activities must have read this Installation & Operating Manual and understood its
contents.
■ Read this Manual in full and follow all instructions.
■ Please also read the instructions for use of any accessories.
■ The Installation & Operating Manual is part of the product package. Keep it in an easily acces-
sible location.
Availability of this Installation & Operating Manual
■ Make sure this Installation & Operating Manual is always available to the operator.
■ If you pass on or sell the equipment to a third party, please also hand over the Installation &
Read the relevant
Installation & Operating Manual
Hazard symbols in this Manual
Danger zone, dangerous situation
Operating Manual.
Illustrations and symbols used
1. Action to be taken
2.
■ Lists
◆ Bullet points in lists
A Keys to illustrations
Additional
information

6NRG 10-52, NRG 16-52 - USA - Installation & Operating Manual - 850696-00
Types of warning
DANGER
Warning of a dangerous situation that results in death or serious injury.
WARNING
Warning of a dangerous situation that may possibly result in death or serious injury.
CAUTION
Warning of a situation that may result in minor or moderate injury.
ATTENTION
Warning of a situation that results in damage to property or the environment.

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NRG 10-52, NRG 16-52 - USA - Installation & Operating Manual - 850696-00
Specialist terms, abbreviations
Here, we explain some abbreviations, specialist terms, etc., which are used in this Manual.
NRGT .. / NRR.. / NRS.. / URS .. / URB .. / SRL .. / etc.
Equipment and type designations of GESTRA AG.
SELV
Safety Extra Low Voltage
Operating point (of the plant)
The operating point describes the operating parameters within which a plant or boiler is operated
in its nominal range. In a steam boiler, for example, these parameters would be output, pressure,
and temperature.
The design data may be a lot more stringent, however.
A boiler that is operated at 145psi (10bar) and 356°F (180°C) may be designed to withstand a
pressure of 870psi (60bar) and a temperature of 527°F (275°C), for example, which is therefore
not necessarily its operating point.

8NRG 10-52, NRG 16-52 - USA - Installation & Operating Manual - 850696-00
Usage for the intended purpose
In combination with NRS 1-.. level switches, the NRG 10-52, NRG 16-52 level electrode indicates
when up to four different water levels have been reached. The level electrode and level switches
are installed in steam boilers and hot water installations or in condensate and feedwater tanks,
e.g., as a water level controller with MIN/MAX alarm.
When used as intended, the level electrode can be combined in a circuit with the following level
switch: NRS 1-56.
Improper use
There is a danger of death due to explosion if the equipment is used in potentially
explosive atmospheres.
Do not use the equipment in potentially explosive atmospheres.
Do not bring any equipment into service that does not have its own specific rating
plate.
The rating plate indicates the technical features of the equipment.
Applicable directives and standards
The equipment has been tested and approved for use in the scope governed by the following
directives and standards:
Standards:
■ UL 60730-1 and CAN/CSA E60730-1
General Requirements for Automatic Electrical Controls
■ UL 60730-2-15 and CAN/CSA E60730-2-15
Requirements for Automatic Electrical Water Level Sensing Controls

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NRG 10-52, NRG 16-52 - USA - Installation & Operating Manual - 850696-00
Danger to life from scalding! Do not remove the level electrode under pressure.
Steam or hot water can spurt forcefully out of the equipment.
■ Only remove the level electrode at 0psi (0bar) boiler pressure.
Risk of severe burns! Do not perform work on a level electrode that is still hot.
The level electrode gets very hot during operation.
■ Allow the level electrode to cool.
■ Always wait for the level electrode to cool before performing any installation and
maintenance work.
There is a risk of electric shock during work on electrical systems.
■ Always switch off the voltage to the plant before performing connection work.
■ Check that the plant is not carrying live voltage before commencing work.
Danger to life! Hot steam or hot water can suddenly escape from a faulty
NRG 10-52, NRG 16-52 level electrode.
Shocks and impacts during transport or installation can result in damage to or leaks in
the level electrode, causing pressurized hot steam or hot water to escape through the
pressure relief hole.
■ To prevent damage during transport and installation, do not expose the electrode
rod to major shocks or impacts.
■ Before and after installation, check that the level electrode is completely undamaged.
■ Check that the level electrode is not leaking when bringing into service.
Attempts to repair the equipment will cause the plant to become unsafe.
■ The NRG 10-52, NRG 16-52 level electrode may only be repaired by the
manufacturer, GESTRA AG.
■ Only replace faulty equipment with identical equipment from GESTRA AG.
Basic safety information

10 NRG 10-52, NRG 16-52 - USA - Installation & Operating Manual - 850696-00
Required personnel qualifications
Activity Personnel
Integration in control system Specialist staff Plant designer
Installation/
electrical connection/
bringing into service
Specialist staff
The equipment may only be installed, wired
and brought into service by qualified and
competent staff.
Operation Boiler service technician Staff trained by the plant operator.
Maintenance work Specialist staff
Fitting and maintenance work may only be
performed by authorized staff who have
undergone specific training.
Refits Specialist staff Persons trained by the plant operator to work
with pressure and temperature.
Notes on product liability
The manufacturer cannot accept any liability for damages resulting from improper use of the
equipment.

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NRG 10-52, NRG 16-52 - USA - Installation & Operating Manual - 850696-00
The level electrode uses the conductivity of the water to measure the level. The switchpoints for
the various water levels are determined by the length of the respective electrode rods.
The level electrode is installed inside steam boilers and tanks or outside in a level pot. For internal
installation, a protective tube provided on site ensures reliable function (see section Installation
examples on p. 19).
The level electrode can be installed in a single protective tube or level pot together with a
GESTRA level electrode for water level limitation or for use as a high level alarm.
Safety information
The equipment may only be installed, wired and brought into service by qualified and competent
staff.
Fitting and maintenance work may only be performed by authorized staff who have undergone
specific training.
Function

12 NRG 10-52, NRG 16-52 - USA - Installation & Operating Manual - 850696-00
Mat-No.:
87psi (6bar)
327°F (164°C)
NRG 10-52
GESTRA AG Münchener Straße 77 28215 Bremen Made in Germany
Pmax
Tmax
1-11,5NPT 1.4404/F316L IP65
Betriebsanleitung beachten
See installation instructions
Voir instructions de montage
Tamb = 158°F (70°C)
NRG 10-52, NRG 16-52
Technical data
Service pressure
NRG 10-52: 87psi at 327 °F (6bar at 164 °C)
NRG 16-52: 464psi at 460°F (32bar at 238°C)
Mechanical connection
Thread 1" - 11.5 NPT
Materials
Screw-in body 1.4404 / F316L
Electrode rods 1.4571, X6CrNiMoTi17-12-2
Insulation, spacer PTFE
Five-pole connector 3.2161 G AlSi8Cu3
Lengths supplied
39.37 in (1000 mm), 59.05 in (1500 mm)
Electrical connection
Five-pole connector, cable glands PG 11
Protection
IP 65 according to EN 60529
NEMA type 1 according to NEMA 250
Admissible ambient temperature
Max. 158°F (70°C)
Weight
Approx. 3.53 lb (1.6 kg) [NRG 16-52 L = 39.37 in (1000 mm)]
Transport temperature
-4°F … 176°F (-20°C … +80°C) (<100hours), only switch on after a defrosting period of 24
hours.
Storage temperature
-4°F … 158°F (-20°C … +70°C), only switch on after a defrosting period of 24 hours.
Other information
Incorporated Type 1 action operating control, passive sensor
Pollution degree 3, impulse voltage 500 V
Equipment designation Safety information
Disposal information
CE marking
Type approval number
Manufacturer Pressure rating, thread type,
material number
Area of
application
Fig. 1
Rating plate, identification
Fig. 2
Input rating: Up to 5Vss
Ambient temperature: 32 158°F (0 70°C)--
Environmental rating: NEMA 1
Wiring: Use Copper Conductors Only,
Use 60/75°C Conductors,
Use No.18 16 AWG Wire Size Only.-
Use with accessory: NRS 1 52, NRS 1-53, NRS 1-54,
NRS 1-55, NRS 1-56
-
OPERATING CONTROL
E513189

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NRG 10-52, NRG 16-52 - USA - Installation & Operating Manual - 850696-00
123
Overall view of the NRG 10-52, NRG 16-52
Fig. 1
A
B
C
Key
A Five-pole connector
B Cover tube
C Electrode thread
D Electrode rods
E Spacer
D
E

14 NRG 10-52, NRG 16-52 - USA - Installation & Operating Manual - 850696-00
Dimensions
Fig. 3
NRG 1..-52 with five-pole connector
10.24 in (260 mm)
1234
0.8 in (20 mm)
Thermal insulation
provided on site
1" - 11.5 NPT
1.2 in (30 mm)
1.35 in
(50 mm)
0.55 in (14 mm)
2.55 - 2.75 in
(65 - 70 mm)
39.37 in (1000 mm), 59.05 in (1500 mm)
Size 41

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NRG 10-52, NRG 16-52 - USA - Installation & Operating Manual - 850696-00
You will need the following tools:
■Open-ended wrench size 41
■Scriber
■Bolt cutter
■Flat file
Preparing for installation
If the equipment is to be installed outdoors, outside the protection of a building,
environmental influences may adversely affect function.
■ Pay attention to the admissible ambient conditions in the technical data,
see page 12.
■ Do not operate the equipment if the temperature is below freezing.
◆ At temperatures below freezing, use a suitable heat source
(e.g., control cabinet heater, etc.).
■ Connect all parts of the plant to a central grounding point to prevent equalizing
currents.
■ Use a cover to protect the equipment from direct sunlight, condensation and
heavy rain.
■ Use UV-resistant cable ducts for routing the connecting cable.
■ Take further measures to protect the equipment from lightning, insects and
animals, and salty air.

16 NRG 10-52, NRG 16-52 - USA - Installation & Operating Manual - 850696-00
Installation
DANGER
Danger to life! Escaped hot steam can cause scalding.
Hot steam or hot water can escape suddenly if the level electrode is unscrewed under
pressure.
■ Reduce the boiler pressure to 0psi (0bar) and check the pressure before
unscrewing the level electrode.
■ Only remove the level electrode at 0psi (0bar) boiler pressure.
WARNING
The hot level electrode can cause severe burns.
The level electrode gets very hot during operation.
■ Always let the level electrode cool down before performing installation and mainte-
nance work.
■ Only remove level electrodes that have cooled down.
ATTENTION
Incorrect installation can lead to malfunctions in the plant or the level electrode.
■Always install the level electrode in a vertical position.
■Take care not to bend electrode rods during installation!
■Avoid subjecting electrode rods to hard impacts.
■Ensure a minimum of 1.2in (30mm) for the electrode tip insulation.
■Do not install the upper part of the level electrode cover tube Bin the boiler’s
thermal insulation!
■Do not coat the electrode thread with conductive paste or grease!
■Make sure there is a creepage path of at least 0.55in (14mm) between the
electrode tips and ground (flange, tank wall). Figs. 5, 6
■Ensure minimum clearances when installing the electrode.
Note
■An NRG 10-52, 16-52 level electrode can be installed in a single protective tube
or level pot [inside diameter 3.94in(100mm)] together with a GESTRA level
electrode, and a compact level switch or transmitter. If the level limiting elec-
trode is installed inside the vessel, it must be at least 1.57in (40mm) away from
the upper pressure relief hole.
■Check the boiler standpipe and flange during the preliminary boiler inspection.
■Installation examples can be found on pages 19 and 20.
■If installed outdoors, the level electrode must be equipped with a GESTRA
weatherproof hood.

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NRG 10-52, NRG 16-52 - USA - Installation & Operating Manual - 850696-00
Function Function
Please enter function!
Electrode rod /
terminal
Length [mm]
Please enter length!
Electrode body Functional ground
e.g., MIN alarm 1
e.g., pump off 2
e.g., pump on 3
e.g., MAX alarm 4
Installation
Installing the NRG 10-52, NRG 16-52, step 1
1. Determine the measured lengths of the electrode tips, enter the dimensions in the
Functions table and mark with a scriber.
2. Cut electrode tips 1234with a bolt cutter.
2. Deburr the end faces of the electrode tips.
3. Strip off 1.95in (50mm) of the PTFE insulation from the lower end of the electrode tip. Make
sure that the remaining insulation measures at least 1.2in (30mm), measured from the
lower edge of the screw thread, see Fig. 3.
Functions table

18 NRG 10-52, NRG 16-52 - USA - Installation & Operating Manual - 850696-00
Montage
Installing the NRG 10-52, NRG 16-52, step 2
■ Make sure that the internal and external threads are in perfect condition.
■ Do not apply more than three windings of PTFE insulating tape around the electrode thread.
WARNING
Do not use too much tape. Do not use fitting lubricants or pastes.
■ Fit the electrode and tighten first with your hand and then with a size 41 open-ended wrench.
Do not use a pipe wrench.
■ Recommendations for tightening torques cannot be given due to the conical/parallel type of
connection.
■ Avoid tightening excessively; part of the electrode thread should always remain visible.
The electrode body does not “sit” on the flange, i.e. the underside of the hexagon is not
in contact with the flange (also see Fig. 4). If it is in contact, the internal thread is outside
tolerance. In this case, the flange must be replaced.
After the electrode has been installed with PTFE sealing tape, you must ensure there is adequate
electrical contact between the electrode and the boiler wall.
To do this, after installation measure the resistance between the electrode body and the boiler with
a multimeter.
The reading must be < 10ohms.
If the reading is > 10ohms, connect the electrode to the boiler wall using a band grounding clamp.
(The band grounding clamp is available as an optional accessory)
Next, measure the resistance again.
The value must be < 10ohms and entered as followed:
Measured resistance: __________________________ ohms
Fig. 4
Boiler wall
Visible thread

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NRG 10-52, NRG 16-52 - USA - Installation & Operating Manual - 850696-00
Installation examples with dimensions
Fig. 5 Protective tube (provided on site) if electrode is used as an internal water level limiter
∅0.8in
(20mm)
∅0.8in
(20mm)
0.8 in
(20 mm)
NPS 2 (DN 50)
1" - 11.5 NPT
≤ 90°
0.39 in
(10 mm)
≥ 0.55 in (14 mm)
1
2
5
6
8
7
9
4
3

20 NRG 10-52, NRG 16-52 - USA - Installation & Operating Manual - 850696-00
Installation example with dimensions
Fig. 6 Level pot for external use
1Flange
2Perform preliminary inspection of standpipe and flange during the boiler inspection
3Protective foam tube/level pot
4Reducer
5Pressure relief hole
6High water HW
7Low water LW
8Electrode tip
9Electrode spacing ≥ 0.55in (≥ 14mm) (air gap and creepage path)
CD Center distance
Key
Pipe diameter
(DN)
CD
1" - 11.5 NPT
1
7
6
3
2
≥ 0.55 in
(≥ 14 mm)
8
9
4
Pipe diameter
(DN)
≥ Pipe diameter/2
(≥DN/2)
≥ Pipe diameter/2
(≥DN/2)