GESTRA NRG 16-51 User manual

Level Electrodes
NRG 16-51
NRG 17-51
NRG 19-51
Original Installation &
Operating Manual
850692-00
EN (USA)
English

2NRG 16-51, NRG 17-51, NRG 19-51 - USA - Installation & Operating Manual - 850692-00
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
Admissible system components....................................................................................................... 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................................................................................................................. 13
Overall view of the NRG 16-51, NRG 17-51, NRG 19-51 .................................................................... 14
Dimensions of the NRG 16-51, NRG 17-51, NRG 19-51 with four-pole connector ........................... 15
Overall view of the NRG 16-51F, NRG 17-51F, NRG 19-51F................................................................ 16
Dimensions of the NRG 16-51F, NRG 17-51F, NRG 19-51F with aluminum terminal box................. 17
Preparing for installation ................................................................................................................... 18
Installation.......................................................................................................................................... 19
Installing the NRG 16-51, NRG 17-51, NRG 19-51, step 1 .............................................................. 21
Installing the NRG 16-51, NRG 17-51, NRG 19-51, step 2 .............................................................. 22
Installing the NRG 16-50F, NRG 17-50F, NRG 19-50F with aluminum terminal box......................... 23
Installing the NRG 16-50F, NRG 17-50F, NRG 19-50F, additional information .................................. 24

3NRG 16-51, NRG 17-51, NRG 19-51 - USA - Installation & Operating Manual - 850692-00
Contents
Installation examples with dimensions............................................................................................. 25
Electrical connection.......................................................................................................................... 27
NRG 16-50, NRG 17-50, NRG 19-50 with four-pole connector........................................................ 27
Connecting the level electrode....................................................................................................... 28
NRG 16-50, NRG 17-50, NRG 19-50 with four-pole connector........................................................ 28
NRG 16-50F, NRG 17-50F, NRG 19-50F with aluminum terminal box.............................................. 28
Wiring diagram .............................................................................................................................. 29
Bringing into service, fault indications and troubleshooting ........................................................... 30
Taking out of service.......................................................................................................................... 30
Removing the NRG 1..-51 level electrode....................................................................................... 30
Removing the NRG 1..-51F level electrode..................................................................................... 30
Disposal .............................................................................................................................................. 31
Returning decontaminated equipment.............................................................................................. 31
UL components................................................................................................................................... 31

4NRG 16-51, NRG 17-51, NRG 19-51 - USA - Installation & Operating Manual - 850692-00
Content of this Manual
Product:
■ Level Electrodes NRG 16-51, NRG 17-51, NRG 19-51
First edition:
BAN 850692-00/08-2021cm
© 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 16-51
1 level electrode NRG 16-51
1 washer with set screw
(enlarged measuring surface) (optional)
1 retaining ring (optional)
1 Installation & Operating Manual
NRG 17-51
1 level electrode NRG 17-51
1 washer with set screw
(enlarged measuring surface) (optional)
1 retaining ring (optional)
1 Installation & Operating Manual
NRG 19-51
1 level electrode NRG 19-51
1 washer with set screw
(enlarged measuring surface) (optional)
1 retaining ring (optional)
1 Installation & Operating Manual

5NRG 16-51, NRG 17-51, NRG 19-51 - USA - Installation & Operating Manual - 850692-00
How to use this Manual
This Installation & Operating Manual describes the correct use of NRG 1..-51 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
accessible 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 &
Operating Manual.
Hazard symbols in this Manual
Danger zone, dangerous situation
Illustrations and symbols used
1. Action to be taken
2.
■ Lists
◆ Bullet points in lists
A Keys to illustrations
Additional
information
Read the relevant
Installation & Operating Manual

6NRG 16-51, NRG 17-51, NRG 19-51 - USA - Installation & Operating Manual - 850692-00
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.

7NRG 16-51, NRG 17-51, NRG 19-51 - USA - Installation & Operating Manual - 850692-00
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 16-51, NRG 17-51, NRG 19-51 - USA - Installation & Operating Manual - 850692-00
Usage for the intended purpose
NRG 1...-51 level electrodes are used in conjunction with the NRS 1-51 level switch as a
high-level alarm for steam boilers and hot water installations.
A high-level alarm prevents the defined high water (HW) level from being exceeded and switches
off the feedwater supply, for example, to achieve this.
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
Applicable directives and standards
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.
Admissible system components
According to UL 60730-2-15, the NRG 1...-51 level electrode can be operated with the NRS 1-51
level switch and regarded as a protective control.
To ensure proper use in all applications, please also read the Installation & Operating
Manuals for the system components used.
■ You can find the latest Installation & Operating Manuals for other system compo-
nents on our website:
http://www.gestra.com

9NRG 16-51, NRG 17-51, NRG 19-51 - USA - Installation & Operating Manual - 850692-00
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 1...-51 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 1...-51 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 16-51, NRG 17-51, NRG 19-51 - USA - Installation & Operating Manual - 850692-00
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.
Fig. 1
Notes on product liability
The manufacturer cannot accept any liability for damages resulting from improper use of the
equipment.