GESTRA LRGT 16-2 User manual

1
LRGT 16-1
LRGT 16-2
LRGT 17-1
KS 90
Installation Instructions 818726-02
Conductivity Transmitter LRGT 16-1
Conductivity Transmitter LRGT 16-2
Conductivity Transmitter LRGT 17-1
Industrial Controller KS 90
GESTRA Steam Systems
EN
English

2
Contents
Usage for the intended purpose ..............................................................................................................5
Safety Note.............................................................................................................................................5
Danger ...................................................................................................................................................5
ATEX (Atmosphère Explosible).................................................................................................................5
Note on the Declaration of Conformity / Declaration by the Manufacturer ..........................................5
Important Notes
Page
Explanatory Notes
Scope of supply......................................................................................................................................6
Description .............................................................................................................................................6
Function ............................................................................................................................................. 6, 7
Installation notes ..................................................................................................................................16
Attention...............................................................................................................................................16
Note .....................................................................................................................................................16
Mounting conductivity transmitter.........................................................................................................16
Installation
Electrical Connection
Technical Data
LRGT 16-1, LRGT 16-2, LRGT 17-1..................................................................................................... 8, 9
Name plate / marking ...........................................................................................................................10
Corrosion resistance.............................................................................................................................10
Sizing ...................................................................................................................................................10
Dimensions...................................................................................................................................11 – 13
Key.......................................................................................................................................................15
Examples of installation .................................................................................................................. 17, 18
Key.......................................................................................................................................................18
Tools.....................................................................................................................................................18
Examples of Installation
LRGT 16-1, LRGT 16-2, LRGT 17-1.......................................................................................................14
Key.......................................................................................................................................................15
Functional Elements
LRGT 16-1, LRGT 16-2, LRGT 17-1.......................................................................................................19
Connecting the conductivity transmitter..........................................................................................19, 20
Key.......................................................................................................................................................20
Safety power supply unit for LRGT 16-1, LRGT 16-2, LRGT 17-1...........................................................21
Tools ....................................................................................................................................................21
Wiring diagram for conductivity transmitter LRGT 16-1, LRGT 17-1 ......................................................21
Wiring diagram for conductivity transmitter LRGT 16-2.........................................................................22

3
Contents – continued –
Page
Fault-finding list for troubleshooting................................................................................................ 30, 31
Cleaning the measuring electrode.........................................................................................................31
Exchanging the electronic insert ...........................................................................................................32
Note .....................................................................................................................................................32
Malfunctions
Correcting the measured value .............................................................................................................27
Checking the temperature coefficient setting Tk....................................................................................27
Adapting cell constant ....................................................................................................................27, 28
Functional test......................................................................................................................................28
LEDs and malfunction indication...........................................................................................................29
Operation
Danger .................................................................................................................................................33
Exchanging the conductivity transmitter ...............................................................................................33
Disposal................................................................................................................................................33
Decommissioning
Basic Settings
Factory setting .....................................................................................................................................23
Establishing measuring range and actual value output ................................................................... 23, 24
Checking temperature coefficient setting Tk..........................................................................................25
Commissioning Procedure
Checking electrical connection .............................................................................................................26
Applying mains voltage.........................................................................................................................26
Note .....................................................................................................................................................26
Industrial Controller KS 90
Usage for the intended purpose ............................................................................................................34
Safety notes..........................................................................................................................................34
Danger .................................................................................................................................................34
Important Notes
Explanatory Notes
Scope of supply....................................................................................................................................35
Function ...............................................................................................................................................35
Technical data ......................................................................................................................................35
Name plate KS 90.................................................................................................................................36

4
Operating structure...............................................................................................................................44
Configuration level........................................................................................................................45 – 48
Parameter level.............................................................................................................................49 – 62
Operating level ............................................................................................................................... 63, 64
Malfunction messages..........................................................................................................................64
Setting up the industrial controller KS 90
Versions
Mounting
Electrical Connection
Connecting the industrial controller KS 90.............................................................................................41
Note .....................................................................................................................................................41
Wiring diagram LRGT 16-1, LRGT 16-2, LRGT 17-1, KS 90 ............................................................. 42, 43
Attention...............................................................................................................................................43
Supply voltage......................................................................................................................................39
Installation in control cabinet door .......................................................................................................40
Attention...............................................................................................................................................40
Note .....................................................................................................................................................40
Example of installation..........................................................................................................................40
Contents – continued –
Page
Dimensions
KS 90 ...................................................................................................................................................37
Functional Elements
KS 90 ...................................................................................................................................................38
Troubleshooting
Fault-finding list for troubleshooting......................................................................................................65

5
Important Notes
Safety note
Danger
When loosening the conductivity transmitter steam or hot water might escape. This
presents the danger of severe scalding. It is therefore essential not to remove the
conductivity transmitter unless the boiler pressure is verified to be 0 bar.
The conductivity transmitter becomes hot during operation. This presents the risk of
severe burns to hands arms when the equipment is touched.
Installation, de-installation and maintenance work should only be carried out when the
system is cold.
The equipment must only be installed and commissioned by qualified and competent staff.
Retrofitting and maintenance work must only be performed by qualified personnel who – through
adequate training – have achieved a recognised level of competence.
Usage for the intended purpose
Use conductivity transmitters LRGT 16-1, LRGT 16-2 and LRGT 17-1 only for measuring the electrical
conductivity in liquids.
When used for conductivity limiting or continuous boiler blowdown in steam boilers the conductivity
transmitters LRGT 16-1, LRGT 16-2 and LRGT 17-1 must only be used in conjunction with the industrial
controller KS 90.
To ensure trouble-free operation the requirements made on water quality according to TRD and EN
regulations must be met.
Use the equipment only within the specified pressure and temperature ratings.
Any type of use differing from the usage described above is considered as improper. The resulting risk
will have to be borne by the user alone. The manufacturer hereby expressly rejects any claims for any
resulting damage.
ATEX (Atmosphère Explosible)
According to the European Directive 94/9/EC the equipment must not be used in explosion risk areas.
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.de/documents or can be requested from us.

6
Explanatory Notes
Scope of supply
LRGT 16-1
1 Conductivity transmitter LRGT 16-1
1 Joint ring 33 x 39, form D, DIN 7603, 1.4301, bright annealed
1 Installation manual
LRGT 16-2
1 Conductivity transmitter LRGT 16-2
1 Joint ring 33 x 39, form D, DIN 7603, 1.4301, bright annealed
1 Installation manual
LRGT 17-1
1 Conductivity transmitter LRGT 17-1
1 Joint ring 33 x 39, form D, DIN 7603, 1.4301, bright annealed
1 Installation manual
Description
The compact-design conductivity transmitter LRGT 16-1, LRGT 16-2, LRGT 17-1 consists of a
conductivity electrode, a temperature sensor for detecting the fluid temperature and a conductivity
transmitting unit incoporated in the terminal box.
The conductivity transmitters LRGT 16-1 and LRGT 17-1 work according to the conductometric
measuring method using two measuring electrodes and the conductivity transmitter LRGT 16-2 works
according to the conductometric measuring method using four measuring electrodes. The equipment
measures the conductivity of electrically conductive fluids (TDS content) and provides a 4-20 mA
measuring current as a function of the detected conductivity value.
The conductivity transmitters are designed for use with the industrial controller KS 90 for conductivity
limiting and continuous boiler blowdown in steam boilers or for conductivity monitoring in condensate
and feedwater systems.
The conductivity transmitters LRGT 16-1, LRGT 17-1 are mainly used in steam boilers with low TDS
content, e.g. steam regenerators, high-pressure boilers or condensate tanks.
The conductivity transmitter LRGT 16-1 is also approved for feedwater monitoring on strips.
The conductivity transmitter LRGT 16-2 is mainly used in industrial boiler plants operating with
pressures up to PN 40 and max. admissible conductivities acc. to TRD/EN of 8000/6000 μS/cm.
Function
LRGT 16-1, LRGT 17-1
A measuring current of variable frequency passes through the fluid, creating a potential gradient
between the measuring electrode and the reference tube which is then used as measuring voltage UU.
LRGT 16-2
The conductivity electrode consists of two current and two voltage electrodes. The current electrodes
direct the measuring current UIwith a fixed frequency into the fluid, thereby creating a potential
gradient between these electrodes. This potential difference is then picked up by the voltage electrodes
and evaluated as measuring voltage UU.

7
LRGT 16-1, LRGT 17-1 und LRGT 16-2
The electrical conductivity is a function of temperature. A resistance thermometer integrated in the
electrode measures the fluid temperatures so as to relate the measured values to the reference
temperature.
The electrical conductivity is calculated from the measuring voltages UUand UIand – as a function of
the adjusted temperature coefficient Tk– linearly based on the reference temperature of 25°C. Once
converted into a conductivity-dependent current signal, an output current of 4 – 20 mA is available for
external use.
The cables leading to the measuring electrode, the reference tube and the resistance thermometer
are monitored and checked for interruptions and short circuits. In addition, the circuit board is pro-
tected against excess temperatures in the terminal box. In the event of a malfunction, the LEDS on the
circuit board will light up or flash and the current signal is set to 0 or 0.5 mA. As a consequence the
controller KS 90 will signal sensor break.
A ten-pole code switch enables the parameterisation of the transmitter, the adaptation of the cell
constant and the activation of a performance test. The electrical conductivity is measured in μS/cm. In
some countries the unit ppm (parts per million) is used (conversion: 1 μS/cm = 0.5 ppm).
Explanatory Notes – continued –
Function – continued –

8
LRGT 16-1, LRGT 16-2, LRGT 17-1
Technical Data
Type approval
TÜV.WÜL.xx-003
GL 33254-06 HH
Service pressure
LRGT 16-1: 32 bar at 238°C
LRGT 16-2: 32 bar at 238°C
LRGT 17-1: 60 bar at 275°C
Connection
Screwed 1" BSP (ISO 228-1)
Materials
Electrode screw-in body: 1.4571, X6CrNiMoTi17-12-2
Measuring electrode(s): 1.4571, X6CrNiMoTi17-12-2
Electrode insulation: PTFE
Terminal box: 3.2161 G AlSi8Cu3
LRGT 16-1, LRGT 17-1: measuring tube/screw: 1.4571, X6CrNiMoTi17-12-2
LRGT 16-1, LRGT 16-2: spacer disk: PEEK
LRGT 17-1: spacer disk: PEEK HT
Measuring length and length of installation (do not cut electrode tips!)
200, 300, 400, 500, 600, 800, 1000 mm (max. 400 mm for marine applications)
Temperature sensor
Resistance thermometer Pt 1000
Measuring cycle
1 sec.
Temperature compensation
Linear, Tkadjustable via code switch
0 % per °C
1.6 – 3.0 % per °C in steps of 0.1
Time constant (measured according to two-bath process)
Temperature: 9 sec.
Conductivity: 14 sec.
Indicators and adjustors
Two LEDs for status messages
One 10-pole code switch for setting:
measuring range
temperature coefficient
cell constant
functional test
Voltage supply
24 V DC (18-36 V DC)
Power consumption
4.5 watt
Fuse
Electronic thermal fuse Tmax = 85 °C, hysteresis – 2 K

9
Cable entry
EMC cable gland with integrated cable clamp, M 20 x 1.5
5-pole screw-type terminal strip, detachable, conductor size 1.5 mm²
Protection
IP 65 to EN 60529
Admissible ambient temperature
Max. 70 °C
Storage and transport temperature
–40 to +80 °C
Weight
Approx. 2.5 kg
Technical Data – continued –
LRGT 16-1, LRGT 16-2, LRGT 17-1 – continued –
LRGT 16-1, LRGT 17-1
Measuring range*) (µS/cm at 25 °C) Current output mA = µS/cm
4 mA
corresponds to
20 mA
corresponds to
100
3000
100
3000
5000 5000
7000 7000
10000 10000
Adjustable via code switch. Max. load for actual value output 750 ohm.
*) Conversion of μS/cm in ppm (part per million): 1 μS/cm = 0.5 ppm
LRGT 16-2
Measuring range*) (µS/cm at 25 °C) Current output mA = µS/cm
Preferred measuring range to 500 µS/cm 4 mA
corresponds to
20 mA
corresponds to
0.5
20
0.5
20
100 100
200 200
500 500
1000 1000
2000 2000
6000 6000
12000 12000

10
Technical Data – continued –
Name plate / marking
Equipment designation
Fig. 1
Pressure rating, screwed
connection, material number
Application specifications
Electric rating
Measuring range
Specification of actual value output
CE marking
Manufacturer
Spare part specifications
Safety note
Corrosion resistance
When used for its intended purpose the safe functioning of the equipment will not be impaired by
corrosion.
Sizing
The electrode body must not be subjected to sharp increases in pressure. The dimensional allowances
and anti-corrosion additives reflect the latest state of technology.
Disposal note

11
1
Technical Data – continued –
Fig. 2 LRGT 16-1
EA
L
Dimensions
E
[mm]
200
300
400
500
600
800
1000
b = 68
A.F. 41
∅ 28
∅ 40
1" to EN ISO 228-1
RA 12.5
RA 3.2
0.5
173
336
20
C
M
1" to EN ISO 228-1
N

12
Technical Data – continued –
Fig. 3 LRGT 17-1
Dimensions – continued –
Cable gland
A
L
E
[mm]
200
300
400
500
600
800
1000
b = 68
A.F. 41
∅ 28
173
336
20
M
1" to EN ISO 228-1
E
N
∅ 40
1" to EN ISO 228-1
RA 12.5
RA 3.2
0.5

13
E
Technical Data – continued –
Fig. 4 LRGT 16-2
Dimensions – continued –
E
[mm]
200
300
400
500
600
800
1000
A
C
E
L
∅ 40
1" to EN ISO 228-1
RA 12.5
RA 3.2
0.5
b = 68
A.F. 41
173
336
20
1" to EN ISO 228-1
∅ 28

14
Functional Elements
Fig. 5
LRGT 16-1, LRGT 16-2, LRGT 17-1
B
G
F
I
H
J
321K
CD
Fig. 6 LRGT 16-1 (without cover plate)
Toggle switch white

15
Technical Data / Functional Elements
1LED 1, green
2LED 2, red
3Code switch
AJoint ring 33 x 39, form D, DIN 7603, 1.4301, bright annealed
BCover screws (cross recess head screws M4)
CEMC cable gland M 20 x 1.5
DHousing cover
EMeasuring length and length of installation
FTerminal strip
GFixing screws for electronic circuit board
HFunctional earth connection
ISeat ring
JFixing nut for terminal box
KTerminal lugs for electrode lines, functional earth
LThermal insulation
MReference tube
NSet screw M 2.5 DIN 913
Key

16
Installation
Attention
The seating surfaces and threads on the vessel and mounting flange must be
accurately machined.
Use only the supplied ring joint 33 x 39, form D, DIN 7603, 1.4301, bright annealed.
Do not insulate the threads with hemp or PTFE tape.
The conductivity transmitter can be installed horizontally or with a vertical inclination.
Be sure that the measuring surface is permanently submerged.
The specified torques must be strictly observed.
Do not lag the terminal box.
LRGT 16-1, LRGT 17-1
Provide a spacing of approx. 30 mm between the lower end of the reference tube and
the boiler wall, the smoke tubes and other metallic fittings as well as the low water
level (LW).
Do not cut the measuring electrode and the reference tube of the conductivity trans-
mitter.
LRGT 16-2
Provide a spacing of approx. 60 mm between the lower end of the reference tube and
the boiler wall, the smoke tubes and other metallic fittings as well as the low water
level (LW).
Do not cut the measuring electrode.
Avoid impacts and shocks to the electrode.
Note
For the approval of the boiler standpipe the relevant local and national regulations
must be observed.
Several examples of installation are shown on pages 17/18.
LRGT 16-1 (for marine applications)
Max. admissible length of measurement and installation: 400 mm.
When installed in steam boilers the conductivity transmitter must be secured against
unscrewing.
Installation notes
Mounting conductivity transmitter
1. Check seating surfaces of threads or mounting flange provided on vessel or boiler standpipe
(see Fig. 2, 3, 4). If necessary re-work the surfaces according to the specification indicated in the
drawing.
2. Place the supplied ring joint Aonto the seating surface Bof the conductivity transmitter.
3. Apply a light smear of silicone grease to the thread of the conductivity transmitter.
4. Screw conductivity transmitter into thread or flange provided on vessel or boiler standpipe and
tighten with an open-end spanner A. F. 41 mm. The torque required when cold is 150 Nm.

17
Examples of Installation
GESTRASteamSystems GESTRASteamSystems
GESTRA
LRGT....
GESTRA
LRGT
µS-ppm
NW
LW
NB
A
Fig. 7
Conductivity monitoring, direct installation of conductivity transmitter via lateral flanged connection
Conductivity monitoring and continuous blowdown control, direct installation of conductivity trans-
mitter via measuring pot and connection of a continuous blowdown valve
Fig. 8
NW
LW
NB
A
GESTRASteam Systems GESTRASteam Systems
GESTRA
LRGT....
GESTRA
LRGT
µS-ppm
LRGT 16-1
LRGT 16-2
LRGT 17-1
4A
4 5 6 8 A
~ 250
415 336
1" BSP
EN ISO 228-1
R*
~ 250
600 336
1" BSP
EN ISO 228-1
R*
197
DN
[mm]
A
[mm]
15 182
20 184
25 184
40 189
R*: LRGT 16-1, LRGT 17-1 R = 30 mm
LRGT 16-2 R = 60 mm
LRGT 16-1
LRGT 16-2
LRGT 17-1
R*: LRGT 16-1, LRGT 17-1 R = 30 mm
LRGT 16-2 R = 60 mm

18
Examples of Installation – continued –
ARing joint 33 x 39, form D, DIN 7603, 1.4301, bright annealed
4Boiler drum
5Shut-off valve GAV
6Continuous blowdown valve BAE
7Measuring pot
8T-type connector
Key
Fig. 9
Conductivity monitoring and continuous blowdown control, installation of conductivity transmitter in
blowdown line via separate measuring pot
M
GESTRASteam Systems GESTRASteam Systems
GESTRA
LRGT....
GESTRA
LRGT
µS-ppm
6
5
1" BSP
EN ISO 228-1
DN 15-40
Outlet
Inlet
DN 15-40 7 A
Tools
Open-end spanner 18 (19) A. F.
Open-end spanner 41 A. F.
Screwdriver for hexagon-socket head screws, size 1.3
Screwdriver for cross-recess head screws, size 1 and 2
LRGT 16-1
LRGT 16-2
LRGT 17-1

19
Electrical Connection
The terminal box is screwed to the electrode by means of a self-locking fixing nut.
Before establishing the electrical connection you can turn the terminal box by max. +/– 180 ° to the
desired position (cable outlet).
A flexible multi-core control cable, min. conductor size 0.75 mm2can be used for wiring.
LRGT 16-1, LRGT 16-2, LRGT 17-1
With the terminal box being open:
1. Undo cover screws B, remove cover D, Fig. 5
2. Detach terminal strip Ffrom circuit board.
3. Unscrew the cap nut Nof the cable gland Cand take out the lamellar insert P, Fig. 10
4. Cut off outer sheath of the cable Sand expose the braided screen Qover a length of approx.
10 – 15 mm.
5. Push cap nut Nand lamellar insert Pwith sealing ring Oonto the cable.
6. Bend braided screen Qoutwards at a right angle (90°).
7. Fold braided screen Qtowards outer sheath, i. e. by 180°.
8. Push lamellar insert Pwith sealing ring Ointo gland body R, turn it briefly around both sides of
the cable axis and snap anti-rotation element into place.
9. Firmly screw on cap nut N.
10. Connect the individual cables according to the wiring diagram to the terminal strip F.
11. Re-attach terminal strip Fto circuit board.
12. Replace cover Dand fasten the cover screws B.
Connecting the conductivity transmitter

20
Connecting the conductivity transmitter – continued –
Electrical Connection – continued –
NCap nut
OSealing ring
PLamellar insert
QBraided screen
RGland body
SShielded cable
Key
Fig. 10
O
RNS
QP