Flowserve NRGS 11-2 User Manual

GESTRA Steam Systems

NRGS 11-2
NRGS 16-2

Installation Instructions 810366-01

Level Electrode Types
NRGS 11-2, NRGS 16-2



1

2

Contents

Page

Important Notes

Usage for the intended purpose ..............................................................................................................4

Safety note ............................................................................................................................................. 4

Danger ...................................................................................................................................................4

Attention .................................................................................................................................................4

ATEX ( Atmosphère Explosible) ...............................................................................................................4

Explanatory Notes

Scope of supply ......................................................................................................................................4

System description .................................................................................................................................5

Function .................................................................................................................................................5

Design ....................................................................................................................................................5

Technical Data

NRGS 11-2, NRGS 16-2 ......................................................................................................................

Corrosion resistance ...............................................................................................................................7

Sizing .....................................................................................................................................................7

Name/marking ........................................................................................................................................7

Dimensions ............................................................................................................................................. 8

Design

NRGS 11-2, NRGS 16-2 .......................................................................................................................... 9

Key ....................................................................................................................................................... 11

Functional Elements

NRGS 11-2, NRGS 16-2 ........................................................................................................................ 10

Key ....................................................................................................................................................... 11

Installation

NRGS 11-2, NRGS 16-2 ........................................................................................................................12

Table 1 .................................................................................................................................................12

Attention ...............................................................................................................................................12

Note .....................................................................................................................................................12

Tools .....................................................................................................................................................12

Example of installation ..........................................................................................................................13

Key .......................................................................................................................................................14

5, 6

Contents continued

Page

Wiring

NRGS 11-2, NRGS 16-2 ........................................................................................................................ 15

Wiring diagram .....................................................................................................................................15

Attention ...............................................................................................................................................15

Tools .....................................................................................................................................................15

Basic Settings

Factiory settings ..................................................................................................................................16

Switch selection fo measuring range ....................................................................................................16

Attention ...............................................................................................................................................16

Tools .....................................................................................................................................................16

Commissioning

Warning ................................................................................................................................................17

Wiring check ......................................................................................................................................... 17

Application of mains voltage ................................................................................................................. 17

Check assignment of switching functions .............................................................................................17

Check low-level alarm .......................................................................................................................... 17

Operation

Resetting low-level alarm .....................................................................................................................17

Troubleshooting

Fault finding list .................................................................................................................................... 18

Annex

Declaration of conformity ......................................................................................................................19

3

4

Important Notes

Usage for the intended purpose

Use level electrodes NRGS 11-2 and NRGS 16-2 only for indicating liquid levels.

Safety note

The equipment must only be installed 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

When loosening the electrode steam or hot water might escape.
This presents the danger of severe scalds to the whole body.
It is essential not to mount or dismantle the electrode unless the boiler pressure is
verified to be 0 bar. The electrode becomes hot during operation. Touching the hot
equipment presents the risk of severe burns to hands and arms. All installation and
maintenance work must only be performed when the equipment is cold.

The terminal strip of the NRGS 11-2, NRGS 16-2 is live during operation.
This presents the danger of electric shock.
Cut off power supply before fixing or removing the housing cover.

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.

ATEX ( Atmosphère Explosible)

According to the European Directive 94/9/EC the equipment must not be used in potentially explosive
areas.

Explanatory Notes

Scope of supply

NRGS 11-2

1 Compact system type NRGS 11-2
1 Joint ring (of stainless steel 1.4301) D 33 x 39 to DIN 7603
1 Installation manual

NRGS 16-2

1 Compact system type NRGS 16-2
1 Joint ring (of stainless steel 1.4301) D 33 x 39 to DIN 7603
1 Installation manual

Explanatory Notes continued

System description

The compact system NRGS 11-2, NRGS 16-2 works according to the conductivity measurement prin
ciple. With the NRGS 11-2, NRGS 16-2 a maximum of 3 levels can be signalled in conductive liquids:

■ Low level alarm, pump ON, pump OFF with a normally open contact
The NRGS 11-2 / NRGS 16-2 has its level switch integrated in the electrode case for the control of all

functions. An external switching device is not required.
The NRGS 11-2 / NRGS 16-2 has two electrode tips for the detection of low water level. The signalling

of the low-level alarm is effected via two separate switching channels.

Function

The conductivity of the liquid is used to signal the liquid level. Some liquids are conductive, which
means that they allow an electric current to flow through them. For the safe functioning of this device
a minimum conductivity of the liquid to be measured is required.
The conductivity measurement method can detect two conditions: electrode tip submerged or ex­posed, meaning switchpoint reached or not reached. Before installation, the length of the electrode
tip must be cut to the required switching levels, e. g. for max./min. alarm, controlling of a valve or
pump.

Designs

NRGS 11-2: Screwed design 1" BSP, EN ISO 228-1, PN 6.
NRGS 16-2: Screwed design 1" BSP, EN ISO 228-1, PN 40. Fig. 1

Technical Data

-

NRGS 11-2, NRGS 16-2

Type approval n°

TÜV · WR/WB · 02-392

Max. service pressure

NRGS 11-2: 6 bar g at 159°C, NRGS 16-2: 32 bar g at 238 °C

Connections

Screwed 1", EN ISO 228-1

Materials
Terminal box Die cast aluminium 3.2161 G AlSi8Cu3

Stem

S.S. 1.4571 CrNiMoTi17-12-2
Housing 1.4571
Flange Forget steel 1.0460 C22.8

Measuring electrodes
Electrode insulation PTFE
Spacer disc PTFE

S.S. 1.4571 CrNiMoTi17-12-2

5

6

Technical Data continued

NRGS 11-2, NRGS 16-2 continued

Lengths supplied

500 mm
1000 mm
1500 mm

Mains supply

230 V +/– 10%, 50/60 Hz
115 V +/– 10%, 50/60 Hz
24 V +/– 10%, 50/60 Hz (option)

Power consumption

5 VA

Fuse
Thermal fuse T

Sensitivity

Range 1: 10 µS/cm
Range 2: 0.5 µS/cm

Electrode voltage

10 V

Output

4 volt-free relay contacts for low level alarm, 1 normally open contact (e.g. for pump).
Max. contact rating with a switching voltage of 24 V, 115 V and 230 V a. c.: resistive 4 A,
inductive 0.75 A at cos ϕ 0.5.
Max contact rating with a switching voltage of 24 V d. c.: 4 A.
Contact material: silver, hard-gold plated.

Indicators and adjustors

2 red LEDs for signalling “Low water”,
1 green LED for signalling “Pump ON”,
1 four-pole code switch for changing sensitivity,
1 button “TEST” for checking low-level alarm
1 button “RESET” for resetting the low-level alarm

Cable entry

Cable gland with integral cable clamp

M 16 (PG 9)
M 20 (PG 16)

Protection
IP 65 to DIN 40050

Max. admissible ambient temperature

70 °C

Weight

approx. 0.8 kg

= 102 °C

max

ss

Technical Data continued

NRGS 16 - 2

NRGS 11 - 2

115/230 V24 V

50 / 60 Hz 5VA 0,5 / 10 µS/cm

TÜV . WR/WB.

02-392

G 1 1.4571

PN 40

PN 6

250 V ~ T 2,5 A

Vor Öffnen des Deckels
Gerät freischalten!
Betriebsanleitung
beachten!

Before removing cover
isolate from power supplies
See installation instructions!

Avant d'ouvrir le couvercle
dèconnecter complètement
l'appareil!
Voir instructions de
montage!

TEST

ENTRIEGELN
RESET
DESENCLENCHER

6 bar ( 87psi)

159°C (318°F)
32 bar (464psi)

238°C (453°F)

Tmax
70°C

(133°F)

IP 65

Pmax
Tmax

GESTRA AG D-28215 Bremen

GB Reg. Design 2 053 113
US Pat. 5 719 342, Design 383 403

Corrosion resistance

Provided that the equipment is used for its intended purpose, its safety is not impaired by
corrosion.

Sizing

The body must not be subjected to sharp increases in pressure. Welds and flanges of the electrode
are designed to withstand dynamic loading (bending and alternating stress). The dimensional
allowances for corrosion reflect the latest state of technology.

Name plate / marking

Fig. 1

7

8

Technical Data continued

Dimensions

173

140

337.5

∅ 42

1", EN ISO 228-1

500, 1000, 1500

Fig. 1

Design

NRGS 11-2, NRGS 16-2

A

50

Fig. 2

D

C

B

∅ 40

≥ 14

65-70

1", DIN 228

N 8

Fig. 3

N 10

0.5

9

10

Functional Elements

GESTRA Steam Systems

GESTRA
NRGS 16-2

N

1 2 3 456 7 8 9 10 11 13

14

12

1 2 3

4

ON

NRGS 11-2, NRGS 16-2

E F G

5

6

Fig. 4

O

N

Fig. 5

123

M

L

4

H

K

J

I

6

5

Design / Functional Elements continued

Key

1 LED „Low-level alarm“

2 LED “Low-level alarm”

3 LED “Pump ON”

4 Code switch “Measuring range”

5 Button “TEST”

6 Button “RESET”

A Thermal insulation, provided on site, ∅ = 20 mm (outside of thermal insulation of steam boiler)

B Seating surface

C Joint ring (of stainless steel 1.4301) D 33 x 39 to DIN ISO 7603

D Electrode thread 1", EN ISO 228-1

E Housing screws M4

F Cable entry PG 9 /PG 11

G Housing cover

H Fixing screws for cover plate

I Separating segment

J Terminal strip

K PE connection

L Terminal strip ‘Test’

M Thermal fuse T

N Plug

O Cover plate

max

102 °C

11

12

Installation

NRGS 11-2, NRGS 16-2

1. Determine required measuring lengths of electrode tips and enter data in

table 1, Fig. 2.

2. Cut electrode tips 1 , 2 , 3 and 4 accordingly.
The electrode tips

1 and 2 (low level limiter) must have the same length.

3. Deburr faces of electrode tips.

4. Strip off 50 mm of PTFE insulation from the ends of electrode tips.

5. Check seating surfaces of threads or flange provided on vessel or boiler standpipe.

6. Place joint ring

C onto seating surface B of electrode Fig. 2. Use only joint ring

Fig. 3

(of stainless steel 1.4301) D 33 x 39 to DIN 7603 supplied with electrode.

7. Apply a light smear of silicone grease (e. g. DOW Corning 111 Compound) to electrode thread

8. Screw level electrode into threads or flange provided on vessel or boiler standpipe and tighten
with a 41 mm open-end spanner. The torque required is 140 Nm when cold.

Table 1

Function Function Electrode tip Length [mm]

Low-level alarm 1
Low-level alarm 2
e. g. Pump ON 3
e. g. Pump OFF 4

Enter data here!

Attention

D.

■

The seating surfaces of the threads or flange provided on the vessel or boiler standpipe

must be accurately machined.

■

Do not bend electrode tip when mounting.

■

Do not lag electrode body.

Note

■

For the approval of the boiler standpipe with connecting flange the relevant local and

national regulations must be considered.

■

See four examples of installation on page 13.

Tools

■

Open-end spanner 41 mm A. F. ■ Bolt cutter

■

Hacksaw

■

Flat file, medium cut

Fig. 3

Installation continued

Examples of installation

1" BSP

1

DN 50

4

∅ 20

2

3

20

5

6

8

≥ 10

≤ 90°
∅ 20

Fig. 6 Fig. 7

¾" BSP

0
!

1" BSP

1
2

DN 20

≤ 1500

4

8

≤ 90°

∅ 20

DN 50

≥ 10

1" BSP

1" BSP

20

∅

≤ 20

1
2

3

20

5
6

0
!

1
2

4

9
3

Fig. 8

DN 100

24.5 24.5

∅ 20

20

4

≤ 3000

5
7

ME

5

8

0

≤ 20

DN 20

13

≤ 90°

∅ 20

0
"

≥ 10

DN 20

Fig. 9

14

Installation continued

Key

Flange PN 40, DN 50 (2"), DIN 2527

1

Flange PN 40, DN 100 (4"), DIN 2527

For the approval of the boiler standpipe with connecting flange the relevant

2

regulations must be considered.

Vent hole

3

High water (HW)

4

Electrode tip ∅ = 5 mm

5

Protection tube DN 80

6

Protection tube DN 100

7

Electrode distance ≥ 14 mm

8

Electrode distance ≥ 40 mm

9

Low water (LW)

0

Reducer K-88.9 x 3.2 – 42.4x2.6 W to DIN 2616, part 2

!

Reducer K-114.3 x3.6 – 48.3x2.9 W to DIN 2616, part 2

"

Wiring

1 2

3 4

ON

1 2 3 4 5 6 7 8 9 10 11 13

14

12

1 223/4

43

N L

115V230

V

24

V

TEST RESET

Alarm

ON

MIN

PE

1

NRGS 11-2
NRGS 16-2

24V

NRGS 11-2, NRGS 16-2

Use multi-core flexible control cable with min. conductor size 1.5 mm² for wiring.

1. Unscrew screws

2. Unscrew union nuts of cable entry

The electrode terminal can be turned through +/- 180°.

3. Loosen plug

4. Turn electrode terminal into desired direction (+/- 180°).

5. Tighten plug

6. Remove terminal strip

7. Connect terminal strip according to wiring diagram, connect PE connection

8. Plug in terminal strips

9. Install cable entry

10. Replace housing cover

Wiring diagram

E, remove housing cover G Fig. 4

F.

N with 17 mm open-end spanner but do not remove. Fig. 5

N slightly.

J from board.

J.

F.

G, fasten screws E and install cable entry.

10 µS/cm

0.5 µS/cm

K.

Fig. 10

Tools

■

Screwdriver for cross head (“Phillips”) screws, size 1

■

Screwdriver for slotted screws, size 2.5; completely insulated according to VDE 0680

■

Open-end spanner 17 mm A. F.

Attention

■

Fuse supply cables with T 2.5 A.

Mains

Relays are shown in the
“power-off” position
(alarm condition)

15

16

Basic Settings

Factory setting

The compact system is delivered with the following default factory settings:

■

Measuring range ≥ 10µS/cm

Switch selection of measuring range

The measuring range can be switch selected between ≥ 0.5 µS/cm und ≥ 10 µS/cm
by means of the code switch 4:

1. Unscrew screws

2. Undo screws

E at the electrode terminal, remove cover G, Fig. 4, Fig. 5

H and remove cover plate O.

2

Code switch 1 – 4 OFF Measuring range

Code switch 1 – 4 ON Measuring range

3. Put cover plate

4. Replace cover

O in place and use screws H to fix it.

G and fasten screws E.

≥ 0.5 µS/cm.

≥ 10 µS/cm.

Attention

■

Do not damage the electronic components when setting the code switch.

Tools

■

Screwdriver for cross head (“Phillips”) screws, size 1

■

Screwdriver for slotted screws, size 2.5; completely insulated according to VDE 0680

Commissioning

Warning

The terminal strip of the NRGS 11-2, NRGS 16-2 is live during operation.
This presents the danger of electric shock.
Cut off power supply before removing or replacing housing cover.

Wiring check

1. Check whether the system NRGS 11-2, NRGS 16-2 has been wired according to wiring
diagram

2. Check whether mains supply corresponds to the wiring of the equipment.

Application of mains voltage

1. Switch on mains supply and check the correct functioning of the equipment at the
corresponding switchpoints.
LEDs 1, 2, 3 are provided for visual check of switchpoints. Fig. 5

Remove housing cover G to check LEDs 1, 2, 3. See Fig. 4 and 5

Check assignment of switching functions

1. Check the switching function “Low level alarm” of the electrode tips and .
For this test the level in the vessel must fall below the low level mark.
The low-level alarm must then be activated by the level switch.

2. Check the switching functions “Pump ON” and “Pump OFF”.

Check low-level alarm

The function of the low-level alarm can be simulated by pushing the button “TEST” 5 . Fig. 5
The low-level alarm must then be activated.

Fig. 10.

2

1

See table 1.

Operation

Resetting low-level alarm

You can reset an activated low-level alarm by pushing the RESET button 6. Fig. 5

17

18

Troubleshooting

Fault finding list

Level has exceeded switchpoint “High Water” – no function

Fault: Mains voltage has not been applied.
Remedy: Apply mains voltage. Wire equipment according to the wiring diagram.

Fault: The thermal fuse has been triggered.
Remedy: In case of defective thermal fuse the mains voltage has not been connected to terminal L:

Replace defective thermal fuse (Order No. 051629)
The ambient temperature must not exceed 70°C.

Fault: The electric conductivity is too low.
Remedy: Set code switch 4 to ≥ 0.5 µS/cm.

Fault: The electrode housing does not have earth connection to the boiler.
Remedy: Clean seating surfaces and insert metal joint ring (of stainless steel 1.4301) 33 x 39 to

DIN 7603. Do not insulate compact system with hemp or PTFE tape!

Fault: Electronic board is defective.
Remedy: Replace board, Order No. 391556 (115/230 V a.c.), 391636 (24 V a.c.).

Level has fallen below switchpoint “Low Water” – no function

Fault: The electrode tips have earth contact.
Remedy: Change installation position.

Fault: The vent hole in the protection tube does not exist, is obstructed or flooded.
Remedy: Check protection tube and, if necessary, provide vent hole.

Fault: The isolating valves of the external measuring pot (optional extra) are closed.
Remedy: Open isolating valves.

Switchpoint has been reached – incorrect function

Fault: The switching function has not been correctly allocated. Electrode tips have been cut to
the wrong size.

Remedy: Identify electrode supply wire and reconnect accordingly.

If faults occour that are not listed above, please contact our subsidiary or agency in your country.

Annex

Declaration of conformity

We hereby declare that the equipment NRGS 11-2 and NRGS 16-2 conform to the following Euopean
guidelines:

■ LV guideline 73/23/eec version 93/68/eec

■ EMC guideline 89/336/eec version 93/68/eec

■ LV standard EN 50178

EMC standard EN 50 081-2, EN 50 082-2

■

This declaration is no longer valid if modifications are made to the equipment without consultation
with us.

Bremen, 3rd January 2005

GESTRA AG

Dipl.-Ing. Uwe Bledschun

Head of the Design Dept.

Dipl.-Ing. Lars Bohl

Quality Assurance Representative

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GESTRA

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GESTRA ESPAÑOLA S.A.

Luis Cabrera, 86-88
E-28002 Madrid
Tel. 00 34 91 / 5 15 20 32
Fax 00 34 91 / 4 13 67 47; 5 15 20 36
E-mail: aromero@flowserve.com

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Flowserve Flow Control (UK) Ltd.

Burrel Road, Haywards Heath
West Sussex RH 16 1TL
Tel. [phone] / 31 44 00
Fax [phone] / 31 45 57
E-mail: gestraukinfo@flowserve.com

Italia

Flowserve S.p.A.

Flow Control Division
Via Prealpi, 30
l-20032 Cormano (MI)
Tel. 00 39 02 / 66 32 51
Fax 00 39 02 / 66 32 55 60
E-mail: infoitaly@flowserve.com

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GESTRA POLONIA Spolka z.o.o.

Ul. Schuberta 104
PL - 80-172 Gdansk
Tel. 00 48 58 / 3 06 10 -02 od 10
Fax 00 48 58 / 3 06 33 00
E-mail: [e-mail]

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Flowserve Portuguesa, Lda.

Av. Dr. Antunes Guimarães, 1159
Porto 4100-082
Tel. [phone]
Fax [phone]
E-mail: jtavares@flowserve.com

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2341 Ampere Drive
Louisville, KY 40299
Tel.: 00 15 02 / 502 267 2205
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E-mail: dgoodwin@flowserve.com

GESTRA AG

P. O. Box 10 54 60, D-28054 Bremen
Münchener Str. 77, D-28215 Bremen
Telephone [phone]
Fax [phone] - 393
E-Mail gestra.ag@flowserve.com
Internet www.gestra.de

810366-01/406cm · © 2004 GESTRA AG · Bremen · Printed in Germany

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