ExTox NH3-20-IS User manual

Instruction Manual
ExTox Transmitter
NH3-20-IS

Instruction Manual
ExTox Transmitter NH3-20-IS
Page 2 of 15
Foreword
We thank you very much for your confidence in our products and us, the ExTox Gasmess-
Systeme GmbH.
The Transmitter NH3-20-IS as well as all other ExTox -Products and services stand for our
high quality targets. Our business is the health protection of mankind, protection of the envi-
ronment and installations. We are glad to take this responsibility. Our Quality Management
System therefore follows ISO 9001 and our Production Monitoring is to keep the European
Directives 2014/34/EU ("ATEX").
With the transmitter NH3-20-IS you profit of the high reliability due to modern sensor tech-
niques and consequent interpretation acc. to the requirements of the regulations and stand-
ards valid for industrial application.
Please do not hesitate to contact anytime in case of questions or if you require information:
ExTox Gasmess-Systeme GmbH
Max-Planck-Straße 15 a
59423 Unna
Germany
Telefon: [phone]
Fax: [phone]
E-mail: info@ ExTox.de
Internet: www. ExTox.de
BA_NH3-20-IS_e_2020-02-17.docx, Stand: 17.02.2020
(Subject to Technical Changes)

Instruction Manual
ExTox Transmitter NH3-20-IS
Page 3 of 15
Content
1Introduction 4
2Features of the Transmitter NH3-20-IS 5
3Indications and Facilities of the Transmitter 6
4Configuration 6
4.1Access to the Parameters 6
4.2Settings 7
5Measuring Mode and Special Modes 8
5.1Measuring Mode 8
5.2Configuration/Maintenance 8
5.3Alarm 8
5.4Faults 8
6Adjustment 9
6.1Manual Adjustment without Calibration 9
6.2Adjustment with Calibration 10
7Installation and Initial Operation 12
7.1Mechanical Installation 12
7.2Electrical Installation 13
7.3Initial Operation 13
7.4Measurement in Pipes at Temperatures of Medium < -5 °C 13
8Maintenance 14
8.1Basics 14
8.2Visual Check 15
8.3Functional Check 15
8.4System Check 15
9Technical Data 15
10Accessories and Spares 15

Instruction Manual
ExTox Transmitter NH3-20-IS
Page 4 of 15
1 Introduction
This Instruction Manual generally describes operation, installation and maintenance of the
following ExTox-Product:
Transmitter NH3-20-IS
▪ Article-No. 291015: Version with integrated electrode
▪ Article-No. 291054: Version with remote electrode, cable length 3 m
Type specific data for each transmitter, such as for example measuring range, measuring
principle and operation conditions, should be taken from a corresponding separate and spe-
cific Data Sheet. This Data Sheet forms consequently part of this Instruction Manual. Refer-
ences on the Data Sheet within this text are marked with DB.
Please read this Instruction Manual carefully before installation and initial operation of the
control unit. We kindly ask you to pay attention to all details and cross-references.
We kindly ask you not to repair the transmitter or to perform any changes which go beyond
the measures described herein. Otherwise you endanger your own safety and your warranty
claims of merchantability. In such cases please contact ExTox or authorised ExTox Service
Partner. Third parties take the responsibility for correct performance of work when mainte-
nance and repairs are done by them.
On receipt of goods please take care that packing and consignment are not damaged and the
goods supplied correspond to the articles described in the delivery note. Please do also com-
pare with your order. In case of any damage please inform your forwarding agent and your
supplier. Please keep the damaged packing.
Please keep in mind that transmitters are sensitive measuring devices and take special care
when unpacking and installing them.

Instruction Manual
ExTox Transmitter NH3-20-IS
Page 5 of 15
2 Features of the Transmitter NH3-20-IS
The transmitter NH3-20-IS serves for ammonia leakage detection in water, in water-/glycol,
in sole and in other fluid mediums. The combination of an interchangeable or immersion fitting
with transmitter enables compact design, which safes mounting space and installation cost.
The use of the ionic-selective measuring principle offers a standard measuring range of 0 to
20 ppm. This means that leakages are recognized obviously earlier than other with conven-
tional detecting systems. Furthermore it allows the selective ammonia detection in all fluid
mediums (pH-range 7 to 12).
NH3-20-IS serves for the preferably early detection of ammonia leakages. An accurate meas-
urement of ammonia concentration should not and cannot be performed by this system. Due
to this the indicated ppm-values are of minor importance. Just a very small ammonia leakage
will lead to an over-scale of measuring range (Indication > 20 ppm) and triggering of alarm.
The transmitter could either be used in closed circuits with a pressure range of 0.5 to 6 bar
(higher pressures if necessary on demand) or in open, pressure-less systems, such as for
example basins or channels. Installation in pipe lines is done via welded sockets (G 1 1/4 A)
and interchangeable fittings, which enable the mounting and dismounting of the electrode
under process conditions. An immersion fitting for pressure-less measurement in open bassins
or channels is also available.
Pipe Open Basin / channels
Transmitter
NH3-20-IS
(incl. measuring con-
verter ET-F)
Immersion Fitting
Measuring adapter
Cooling water
tray
Welded socket VA
Basin/Channel
Pipe
009009009009009009009009009009009
Remote
Measuring con-
verter ET-F
Measuring line
(max. 3 m)
Electrode
Measuring adapter
Basin with
Connecting Sleeve

Instruction Manual
ExTox Transmitter NH3-20-IS
Page 6 of 15
3 Indications and Facilities of the Transmitter
The Transmitter NH3-20-IS consists of measuring electrode and measuring converter ET-F.
The display serves for indication of actual measuring values during measuring mode. During
configuration and calibration of the transmitter the parameters to be set and the correspond-
ing value are indicated. During these modes entering of values is done via four selection keys
directly at the unit.
4 Configuration
4.1 Access to the Parameters
To avoid unintended changes of the configuration data and calibration settings, the transmit-
ter disposes of code protection.
For Release of the input levels (service mode) the following steps are necessary:
 Keep Keys "" and "CR" pressed at the same time for minimum 1 s
 Release the keys
 Keep key "" pressed for minimum 1 s
 Release the key
 After successful release the Operation LED changes from permanent light to blinking light.
You can now choose the different parameters cyclically by means of the key "MODE" and set
them according to the description in the following paragraph.
There is no evaluation of alarms and the output current of the transmitter is constantly 4 mA
during your operation in the levels of parameter setting.
To Lock the input level again and to change to the measuring mode the following steps are
necessary:
 Change to the indication of measured values "… ppm" by means of key "MODE"
 Keep key "CR" pressed for minimum 1 s
Status LED:
 Fault (yellow)
 Alarm (red)
 Power (green)
Display for indication
Of measured values
and Configuration
Selection keys

Instruction Manual
ExTox Transmitter NH3-20-IS
Page 7 of 15
 Release the key
 After successful locking the Operation LED changes from blinking light to permanent light.
4.2 Settings
The table shows all parameters. Their meaning and the possibilities of setting are described
in the same order as they appear on the display when they are selected by means of the key
"MODE".
Parameter Meaning and Possibilities of Setting
Indication of
Measured values
(… ppm)
After releasing the access level (see 4.1) the actual measured value
is still displayed.
Measuring Range
(MB)
The end value of measuring range can be chosen in steps of 0.1 ppm.
The maximum value is 99.9 ppm.
The measuring range always starts with 0 ppm.
The setting only affects scaling of the 4…20 mA output:
 4 mA correspond to 0.0 ppm
 20 mA correspond to the end values of measuring range
Remark: The measured value is always indicated in a range to 99.9
in the display of the control unit ET-F.
Standard setting: 20.0 ppm
Measuring Voltage
Zero Point (UL)
See Adjustment (see 6)
Concentration
of Test Solution
Sensitivity (KH)
The concentration of the Test solution which is used for calibration
and adjustment of the sensitivity of the transmitter has to be entered
(see 6.2).
The value can be chosen in steps of 0.1 ppm. The maximum value is
99.5 ppm.
Standard setting: 10.0 ppm
Measuring voltage
Sensitivity (UH)
See Adjustment (see 6)
Alarm Level (AL) The alarm level fixes at which concentration the alarm relay is trig-
gered.
The value can be chosen in steps of 0.1 ppm. The maximum value is
99.5 ppm.
Standard setting: 10.0 ppm
Hysteresis (HY) The alarm expires only when it is around the value of hysteresis below
the alarm level. This function serves for prevention of permanent re-
peating of alarm triggering due to slight variations of measured val-
ues around the alarm level.
The value can be chosen in steps of 0.1 ppm. The maximum value is
99.5 ppm.
Standard setting: 0.0 ppm, i. e. deactivated.

Instruction Manual
ExTox Transmitter NH3-20-IS
Page 8 of 15
5 Measuring Mode and Special Modes
Please note that a downstream evaluation systems has to interpret the transmitter signals
correctly to recognize special modes and to arrange for suitable safety related measures.
When using ExTox-Control Units the correct interpretation is ensured.
5.1 Measuring Mode
During Measuring Mode the transmitters issues the concentration measured value via the 4-
20 mA Interface. 4 mA corresponds to the zero point, 20 mA corresponds to the end value of
measuring range of the transmitter. The calibration curve is linear. In case of under-scale or
over-scale of measuring range the output current follows the correspondingly continued and
linear calibration curve. Alarm and fault relays are closed.
Please pay attention to the fact that the task of the transmitter NH3-20-IS mainly is quick
detection of leakages when interpreting the measured value. Accuracy of the issued measured
value is limited. Any use for analytical purposes is not intended.
Due to the very high detection sensitivity of the ionic selective measurement any entry of
ammonia into the measuring medium will generally cause a very quick over-scale of the alarm
level and of the end level of measuring range. In contrast low values below the alarm levels
have to be explained by drifting at the electrode and not by ammonia in the sole.
5.2 Configuration/Maintenance
In case the input level is activated the transmitter constantly issues 4 mA and the green
Power LED is blinking. Alarm and fault relays remain closed.
5.3 Alarm
In case the set alarm level is over-run, the relay of the alarm output de-energizes and the
red Alarm-LED is on.
5.4 Faults
In case the transmitter recognizes an internal fault, for example with the integrated controller
or storage monitoring, the relay of the fault output de-energizes and the yellow Fault-LED is
on. The transmitter issues an output current of 1.5 mA as fault indication for downstream
systems if the occurred fault allows this.
Interruptions or short-circuits in the leads of the transmitter cable as well as power failure at
the transmitter lead to a current output of 0 mA or above 20 mA.

Instruction Manual
ExTox Transmitter NH3-20-IS
Page 9 of 15
6 Adjustment
On site a complete adjustment is only possible with limitations. The electrode of the NH3-20-
IS needs a long running-in time in the medium until a balanced condition is finally reached.
When applying test solutions it is inevitable to take the electrode out of the measuring adapter
and with this to disturb the balanced condition. After finishing the adjustment and rebuilding
the electrode into the measuring adapter a drifting of the zero point can be observed for up
to two days. Due to this two adjustment procedures are described hereafter.
6.1 Manual Adjustment without Calibration
We recommend this procedure for slight corrections which could occur due to displacements
of the zero point position. These influences occur due to changes of the medium / ambient
temperature or the composition of the sole, for example adding an additive. On this, only
displacements of few ppm below the alarm level can be observed. In case the alarm level is
reached or in case of bigger deviations this procedure should not be performed before an
ammonia leakage or damage of the electrode could be excluded:
1. Release service mode (see 4.1). On successful release the green Power-LED changes from
permanent light to blinking light.
2. Press the key "MODE" as often until UL=xxxx (xxxx=Measured value) is indicated.
3. Note the indicated value (typically between 1900 and 2400).
4. In case one or more of the following states are recognized, it has to be checked via the
ammonia test set whether the sole is free from ammonia by means of a probe.
 UL out of the above mentioned typical range
 NH3-20-IS is in over-scale of measuring range
 NH3-20-IS indicates values above 15 ppm.
In case the sole is free from ammonia, it is a malfunction of the electrode. In this case the
electrode has to be checked and maintained or changed. Only after running in phase of
the electrode the re-check can be done again (starting again with Step 1).
In case the sole is not free from ammonia, the electrode works correctly. Adjustment
should not be changed. (Stop of adjustment).
5. Press the keys "^" and "v" simultaneously, ULm=xxxx is indicated.
6. Set the value which has been noted under 3. by means of the keys "^" and "v".
7. Press the key "CR"; "SAVE" is indicated for a short time.
8. Press the key „MODE“ as often until UH=xxxx is indicated.
9. Press the keys "^" and "v" simultaneously; UHm=xxxx is indicated.
10. Add 400 to the value noted under 3. and enter the result by means of the keys "^" and
"v".
Remark: The value 400 states the throw of the electrode. The value has been chosen so
safety related that alarming in time is ensured.
11. Press the key "CR"; "SAVE" is indicated for a short time.
12. Lock the Service Mode (see 4.1). After successful locking the green Power-LED changes
from blinking light to permanent light.

Instruction Manual
ExTox Transmitter NH3-20-IS
Page 10 of 15
6.2 Adjustment with Calibration
The described procedure following below is used on factory sided calibration by ExTox. It is
hardly possible to perform this on site and requires experience on handling of the IS-Electrode
and reference solutions. This should only be performed by trained personal and in particular
cases. For securing the functionality for the designated measuring task the procedure de-
scribed in 6.1 is sufficient.
For calibration the following is needed:
 small sample (ca. 50 ml) of the cooling medium of which the ammonia content should be
monitored. It has to be ensured that the cooling medium does not contain any ammonia
at the time of sampling. Otherwise the zero point cannot be set correctly.
 reference solution 100 mg/l Ammonium in water.
You have to take the electrode out of the measuring adapter or immersion fitting in order to
perform the calibration. Please pay attention to the installation hints in Chapter 7.
Attention:
1. Before taking out the electrode you always have to remove the plug of the electrode at
first.
2. Protect the membrane at the bottom of the electrode against touching and damages.
3. Protect the electrode against contamination on the following steps, for example by laying
a clean paper underneath.
Zero Point Position
Leave the input level (Service Mode, see 4.1) and select the menu item Measurement Voltage
Zero Point (UL). The shown value indicates the measuring signal of the electrode.
Now merge the electrode into the cooling medium you have sampled before. Please wait until
the value indicated on the display has stabilised. Then accept this value as new zero point by
pressing the key "CR".
Adjustment of Sensitivity
Now please mix the sample of the cooling sole with the reference dilution in ratio 9:1 (for
example 45 ml cooling sole and 5 ml reference dilution). This mixture forms the test dilution
for a measuring value of 10 ppm Ammonia.
In case you want to use another ammonium reference dilution or another mixture ratio, you
could calculate the calibration value according to the following formula:
Calibration value (in ppm) =
Ammonium concentration (in mg/l) ▪quantity reference dilution (in ml) /
Total quantity sample and reference dilution (in ml)
Please keep in mind that the resulting mixture only has a short lifetime. The mixture should
therefore be produced right before the adjustment (< 1 h).
Select the menu item Concentration Test Dilution Sensitivity (KH) and enter the calibration
value. Then change to the menu item Measurement Voltage Sensitivity (UH).
Merge the electrode into the test dilution. Please wait until the value indicated has stabilised.
Then accept this value as new sensitivity setting by pressing the key "CR".

Instruction Manual
ExTox Transmitter NH3-20-IS
Page 11 of 15
Zero Point Adjustment
Put the transmitter now into the fitting again. Change now to the indication of measured
values and wait until a stable measured value is set. In case the value is different from zero,
correct the setting by using the arrow keys. The sensitivity set before is not influenced by
this.
Finish
The transmitter is now adjusted. Finish the procedure by locking the service mode (see 4.1).
If necessary repeat the zero point adjustment again after 48 h after the balanced condition is
finally reached.

Instruction Manual
ExTox Transmitter NH3-20-IS
Page 12 of 15
7 Installation and Initial Operation
To open the measuring adapter you have to remove the two blind plates at the left and right
side of the front part of the housing. You will find altogether four screws which keep the two
parts of the housing together.
The electrode is connected to the measuring converter by means of the pre-assembled elec-
trode cable. The plug of electrode is now plugged on and then tightened by screwing. Inside
the measuring converter there is a lock bush for the other end of the cable.
Attention: All electrical contacts of the electrode, the electrode cable and the lock bush inside
the measuring converter have to be treated very carefully. Defects, dirt or humidity may lead
to permanent damages.
On installation the following order has to be kept:
 Only for remote electrode: install measuring converter
 Screw electrode into measuring adapter or immersion fitting.
Attention: Especially the membranes at the bottom of the electrode have to remain entire
during installation. Even smallest defects lead to loss in function.
 Connect electrode cable.
 Only for integrated electrode: put on measuring converter and fix with clamp ring.
Please pay attention to the hints in the technical data sheet (DB).
When installing the transmitter in pipes an adaptation of the measuring converter to the
system pressure might probably be necessary.
Attention: Deviations of this information and the actual operating conditions may lead to
malfunctions. In this case please contact ExTox to clarify the case and to adjust the transmit-
ter if necessary. The same is valid for permanent change of the operating conditions.
7.1 Mechanical Installation
When mounting the transmitter it has to be ensured that the transmitter remains accessible
for maintenance. It has to be ensured that the transmitter can be taken out of the fitting.
Therefore it is necessary to keep enough space above the transmitter.
The electrode has to be installed preferably in vertical position; a deviation of more than 45°
is in no way permissible.
Please protect the transmitter against direct climatic influences. Especially direct solar radia-
tion should be avoided. When mounting the transmitter outside it has to be protected against
rain.
There should not be big fluctuations of pressure inside the cooling system (± 0.5 bar to be
not exceeded) and the transmitter has to be mounted free from vibrations.
The measuring electrode always has to immerge into cooling mediums otherwise malfunctions
cannot be avoided during measurement. When measuring in basins or channels the bottom
of the immersion fitting has always to be below the fluid level. If necessary this can be ensured
by mounting a cooling water tray (see accessories). When measuring in pipes the measuring
converter has to be installed that way that the interior of the measuring adapter is always in
contact with the medium inside the pipe.
When using the measuring adapter for pipes, a suitable collecting tray which collects the little
leaking medium quantity (ca. 1 – 2 l/year) is also supplied. The removal of fluid is done by

Instruction Manual
ExTox Transmitter NH3-20-IS
Page 13 of 15
means of a 4/6 hose (mm Inner/Outer ) at the provided hose connection of the measuring
adapter. On demand it is possible to extend the supplied hose or exchange the collecting tray,
as long as the outlet of the fluid out of the measuring adapter could be done without inter-
ruption. The collecting trays have to be drained regularly and manually.
7.2 Electrical Installation
Installation is only to be done by qualified personnel keeping the respective installation
regulations. It is not allowed to install the transmitter in hazardous areas.
There are four cable glands for passing through the transmitter cable as well as the lines for
the relay and fault outputs. To open the control unit you have to remove the two blind plates
at the left and right side of the front part of the housing. You will find altogether four screws
which keep the two parts of the housing together.
The clamp connection is described in the Transmitter Data Sheets (DB).
Connection of the power supply and the current output is done via 3-line, double shielded
line. The ExTox transmitter cable disposes of the described features.
The wire cross-section and the corresponding line resistance determine the maximum dis-
tance between transmitter and control unit (DB). The cable has to be passed protected
against mechanical damage. This could be done by passing the cable through suitable areas,
in tubular cable protection or on cable platforms.
7.3 Initial Operation
After termination of the installation work the transmitter can be put into operation. This is
done automatically when connecting the power supply. Check the power supply at the trans-
mitter. It should not be less than 18 V DC. Please take into consideration the occurring voltage
drop on the transmitter cable from the control unit to the transmitter.
It has to be ensured that the measuring adapter or the immersion fitting are tight. When
using the measuring adapter the cut off cock to the pipe has to be opened. Check moistening
of the electrode with medium. Prior to this fill in a little quantity of the medium into the
electrode chamber of the measuring adapter.
Application of the medium should have been done minimum two days before adjustment
according to Chapter 6.1.
7.4 Measurement in Pipes at Temperatures of Medium < -5 °C
The ionic selective electrode is only suitable for operation in a temperature range between -
5 °C and +50 °C, which only has to be kept at the installation place of the electrode in the
measuring adapter. Inside the measuring adapter a nearly complete isolation of the electrode
chamber from the measuring medium takes place. In the installation socket the exchange of
fluids is reduced.1A Temperature level will be set at the electrode which is between medium
and room temperature. Measurement up to a medium temperature of approx. -20 °C is pos-
sible under usual installation conditions. For lower temperatures additional measures are nec-
essary. We recommend checking this with ExTox.


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ExTox Transmitter NH3-20-IS
Page 14 of 15
8 Maintenance
The electrodes of the transmitter are subject to aging and wear, which depend very much on
the environmental conditions being present at the location. This is the reason why the elec-
trodes of the transmitter are excluded of warranty.
Each transmitter is adjusted by ExTox before delivery takes place. The state of transmitter is
documented in the test certificate of the transmitter, which is enclosed in each delivery.
For regular maintenance the following works are generally set in combination with the manual
adjustment according to Chapter 6.12:
 Annually: change of membrane cap including change of electrolyte fluid
 Every two years (guiding value): Change of the complete electrode
The following descriptions in Chapters 8.1 to 8.4 are in general valid for gas detection systems
of the Company ExTox GmbH, consisting of Control Units and corresponding transmitters.
They have correspondingly to be transferred to the transmitters NH3-20-IS.
8.1 Basics
Maintenance done by specialists is an indispensable measure for checking and keeping the
functionality of gas detection systems. Maintenance comprises inspection, calibration and ad-
justment as well as functional test of the complete system.
Most important is the testing of the connected transmitters. Control of the gas detection sys-
tem and its correct functionality are also checked.
ExTox recommends for all of her supplied transmitters regular calibration and adjustment
with test gas during functional and system checks. Please see also the details in the corre-
sponding Technical Data Sheets (DB). An extension to 12 months might eventually be pos-
sible in case of existing experiences on similar applications. The functionality of the Control
Unit has to be tested as well.
National valid regulations to define maintenance intervals may exist. In Germany it is for
example necessary in certain applications to keep Betriebssicherheitsverordnung (BetrSichV)
and the rules DGUV3-Information 213-056 (Merkblatt T021) and 213-057 (Merkblatt T023)4.
ExTox recommends generally speaking the application of the measures described in this rules
as well as the maximum calibration intervals even if the application does not fit into their
scope.
2A check with a solution containing ammonia in according to the procedure described in 6.2 can additionally be done, but it is not
required.
3 DGUV: Deutsche Gesetzliche Unfallversicherung ("German Statutory Accident Insurance")
4 English versions available

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ExTox Transmitter NH3-20-IS
Page 15 of 15
Maximum Intervals
Explosion Protection
(DGUV-I 213-057, T 023)
Toxic Gases/Vapours and Oxygen
(DGUV-I 213-056, T 021)
1 Month (Visual Check)
4 Months (Functional Check)
1 Year (System Check)
1 Month (Visual Check)
4 Months (Functional Check)
1 Year (System Check)
You as user of the gas detection system bear the responsibility for the correct performance
of the maintenance. ExTox as manufacturer can only place all necessary details to build up
your specific maintenance concept at your disposal. We are glad to support you with this task
and to submit a maintenance quotation acc. to your special requirements.
The result of each maintenance should be documented even if it is not specifically required.
Hereafter the main contents of the intended checks are described. You will find details in the
above mentioned bulletins.
8.2 Visual Check
You have to check your system on mechanical damages, dust, dirt, state of a sampling system
if included. Furthermore indications and status messages have to be checked.
8.3 Functional Check
The functional check also comprises calibration and adjustment. In case of combination with
sampling systems their correct function has also to be checked. It is not necessary to trigger
the switching functions.
A functional check should only be done, if there is no alarm present. You should ensure the
same environmental conditions during this process as valid for the measuring process.
Make sure that measures have been taken to avoid unintended triggering and transmission
of alarms before applying test gas. Activate the alarm bypass in service mode at your trans-
mitter NH3-20-IS or in maintenance mode of your ExTox Control Unit, deactivate automati-
cally triggering protection measures or inform the responsible maintenance personnel. The
measures corresponding to your application have to be determined and the person in charge
for maintenance has to be familiar with all details.
8.4 System Check
The system check additionally comprises the triggering of switching functions; check of sys-
tem parameters and of indication and recording facilities.
9 Technical Data
Please see the Technical Data Sheet for all technical details (DB).
10 Accessories and Spares
Please see Technical Data Sheet (DB).