Airsecure TPK20 Operating instructions

Pressure Dew point monitoring device
TPK 20
Functional description and
operating instructions

List of Contents
1 Scope of supply..................................................................................................................3
2 General dangers and precautions ....................................................................................4
2.1 Safety instructions for electrical connection ...................................................................4
2.2 Safety instructions for compressed air systems..............................................................5
3 Important application notes...............................................................................................6
3.1 Avoiding damage to the measuring probe......................................................................6
3.2 Calibration and measuring accuracy..............................................................................6
3.3 Intended application.......................................................................................................6
4 Humidity measurement in compressed air systems.......................................................7
5 Features..............................................................................................................................7
5.1 Typical areas of application............................................................................................7
6 Function .............................................................................................................................8
7 Functional scope................................................................................................................8
8 Mounting of the device......................................................................................................9
8.1 Safety instructions..........................................................................................................9
8.2 Application notes............................................................................................................9
8.3 Procedure for Installation .............................................................................................10
8.4 Mounting.......................................................................................................................10
9 Connection at the compressed air network...................................................................11
9.1 Direct stationery assembly at the compressed air line..................................................11
9.2 Stationery assembly over hose.....................................................................................11
9.3 Application of a pre-filter/water separator.....................................................................12
9.4 Mounting examples......................................................................................................12
9.5 Adjustment of diverting throttle.....................................................................................13
9.6 Connection of power supply.........................................................................................13
9.7 First time operation.......................................................................................................13
9.8 For the rarest of the cases............................................................................................14
10 Operation........................................................................................................................15
10.1 View of device front and the control elements............................................................15
10.2 Description of the Displays.........................................................................................16
10.3 Operation of keys.......................................................................................................16
10.4 Switching on the device..............................................................................................17
10.5 Changing the alarm and Hysteresis value..................................................................18
10.5.1 Switching ON/OFF of alarm generator and indicator LEDs..................................19
10.5.2 Behaviour during alarm........................................................................................19
10.6 Changing the temperature units.................................................................................20
11 Technical data.................................................................................................................21
11.1 Drawing.......................................................................................................................22
12 Connection of external components............................................................................23
12.1 Layout of extension socket in the device....................................................................23
12.1.1 External Signal generator.....................................................................................24
12.1.2 Alarm output.........................................................................................................25
12.1.3 Analog output.......................................................................................................25
12.1.4 RS 232 / 485-Interface.........................................................................................26
12.1.5 Software PCLOG..................................................................................................26
13 Special type of applications..........................................................................................27
13.1 Stationery mounting location with cooling segment....................................................27
13.2 Portable measurements.............................................................................................27
13.3 Maintenance work......................................................................................................28
14 Trouble shooting guide .................................................................................................29
14.1 The measured value is flow dependent and too high (i.e. too humid).........................29
14.2 The measured value is too high (i.e. too humid).........................................................29
14.3 The measured value is too low (i.e. too dry)...............................................................30
14.4 The measured values varies significantly...................................................................30

15 Appendix.........................................................................................................................31
15.1 Condensate formation in compressed air plants.........................................................31
15.2 Pressure dependence of Dew point............................................................................31
15.3 Thermodynamic concepts...........................................................................................33
16 Working of an adsorption compressed air dryer.........................................................34
17 Checking the measuring accuracy...............................................................................35
18 Working principle...........................................................................................................35
18.1 Format of data transfer at the serial interface ............................................................37
19 EG-Conformance details................................................................................................38
20 Guarantee........................................................................................................................38
21 Accessory list.................................................................................................................39

1 Scope of supply
The Pressure dew point monitoring device is supplied in ready-to-use condition. The scope
of supply includes a plug-in power supply unit, a mounting bracket as well as all components
for hose connection 6 / 4 mm.
Additionally, you may require these items, if necessary:
Mounting materials, screws, dowel
Compressed air hose 6 / 4 mm (ATTENTION! Use only PTFE hose!)
Further nipples, reduction or interconnection joints, if direct mounting is to be done on a
pipeline
Electrical accessories for connection to a super level regulation system
Special accessories like external alarm light, terminal adapter, PC-connection cable (see
accessories overview)
The operating instructions of this device should be read before commissioning.
Besides operating instructions, you will also find important information on mounting,
commissioning and trouble shooting in the relevant chapters.

2 General dangers and precautions
Please carefully read the following precautions before putting into operation! The
symbols used in the operating manual are to make you careful, before hand,
regarding safety considerations and dangers. But all these symbols used cannot
substitute the text of the associated safety instructions in any way. Therefore, the
instructions should also be always read completely!
This symbol indicates likely danger for persons, material or environment. The
information provided in the associated text should be duly followed to avoid any kind
of risk.
This symbol refers to important application notes and tips, which are necessary for
successful working and should be absolutely followed to ensure good results.
2.1 Safety instructions for electrical connection
The device should be operated with only safe low voltage. All other electrical
connections of the device should also be made with only electronic components
which work on safe low voltage.
There if fatal danger in touching the live parts. Therefore, fitment and maintenance of
the regulator shall be carried out by only trained personnel. Mounting and servicing
operations should be carried out only after switching off the voltage.
Touching the plug or other electronic components should also be avoided in switched
off condition. Electronic components can get damaged due to electrostatic discharge
process.
The product is not meant for systems, which perform safety related functions. In
normal operation also, there is always a danger of malfunctioning, for example
because of over voltage or failure of components. The user has to ensure that there
are no consequential damages due to malfunctioning or undefined device status. This
can be achieved, for example, through redundant components or protection circuits.
Due to wrong tightening torque applied on screws of the connection terminals or by
use of inappropriate tool, the terminals can get damaged because of which the
insulation or the contact can get disturbed. Badly connected leads can come out
during operation and cause a serious risk to safety. Excessive heat generated due to
contact resistance at the terminal connections can lead to fire. Wrongly wired
connections can destroy electric components and cause other damages.

2.2 Safety instructions for compressed air systems
The energy stored in the compressed gas can lead to unforeseen events causing
damage to objects or injury to persons. The risk increases with the operating
pressure in the plant. Therefore, all activities are to be executed by only suitably
trained personnel. For all activities in the compressed air system, a commensurate
alertness is necessary in order to avoid damages!
The loud air release noise, in case of uncontrolled opening of lines under pressure,
can damage the hearing or create panic to other persons in the vicinity.
At higher flow velocities, the swept along foreign bodies can act like projectiles and
cause injury to skin or eyes.
The attached measuring chamber with probe is suitable up to 17 bar. This maximum
allowable operating pressure should not be exceeded. Components connected in
series should alsoberated as per the operating pressure and application temperature
of the plant.
By opening the probe housing, removing the sinter cap and improper handling or
forceful application shall make the product devoid of guarantee claims.

3 Important application notes
3.1 Avoiding damage to the measuring probe
Instruments are sensitive and must be treated carefully: Avoid impact, shocks and
vibration.
The sinter filter protects the sensor against mechanical effects and contamination. Do
not remove the filter. Use the measuring probe only with sinter filter in intact
condition!
Before installation, ensure that the measuring point has no condensed water, oil or
dirt secretion! If this is the case, then first put the system in order and dry up!
The measuring system is not suitable for strong oil laden compressed air, since an oil
film on the sensor directly restricts the response behaviour, chokes the pores of the
filter and damages the diverting throttle.
General principle: If you have doubts, you should contact the manufacturer before
you risk errors and cause damage by experimenting on the object!
3.2 Calibration and measuring accuracy
Before delivery, the pressure dew point probes are adjusted and checked at multiple
temperature and humidity points through a sophisticated calibration process. An
adjustment by the end user is not possible.
Please observe the permissible application temperature range. The measuring
accuracy becomes worse at higher temperatures. Exceeding the temperature limit
damages the measuring probe.
The specified data, specially the achievable measuring accuracy, is applicable at 20
°C. General principle: lower is the temperature at the probe, more exact is the result of
measurement. If possible, the measurement should be taken at a coldpoint or the gas
can be cooled down to ambient temperature.
The reference cells, available as accessories, are ideally suitable to check the
measuring accuracy uptoapprox.-10 °C tpd. The application guidelinesmust be duly
followed and before application, the cells are to be checked as per the application
manual! To be always used with unscrewed sinter cap! Further information can be
obtained on request.
With proper application, the measuring probe can be used over many years.
Nevertheless, in order to rule out any error, we recommend 12 months calibration
periodicity, particularly during application of the measuring probe in critical
applications in the lower dew point measuring range.
3.3 Intended application
The pressure dew point probe is intended for measurement of pressure dew point in
clean, dry and oil free compressed air. The range of application is right from -40... +60
°C, with which the calibrated application range is reduced to -10 ... +45 °C. The
accuracy specified in the technical data sheet is at 20 °C. The permissible operating
pressure of the standard version is 0... 17 bar (0... 1.7 MPa).

4 Humidity measurement in compressed air systems
In the industry, there are always high quality requirements for the compressed air. Humidity
and condensate arenot allowed in the compressed air because these often lead todamages
on the machines and loss of quality in production. Therefore, normally compressed air dryers
are used to reduce the humidity content in air for correct application and to provide high
quality compressed air.
However, problems in the dryer are often detected very late, normally only when the damage
has already occurred. By that time, a large amount ofhumidity would have already deposited
in the compressed air network, which has to be again dried up with large expenses. Hence,
the high quality standards in the industry require a continuous humidity monitoring, that is
reliable and has long term stability. Only then the problems can be recognized early, before
the damages occur.
The TPK 20 with its measuring range of -20... +40 °C tpd is the ideal measuring system for
monitoring of cold, adsorption and membrane dryers. The device is primarily meant for
stationery applications, however, because of its simple connection, it is also suitable as a
portable instrument.
5 Features
Pressure dew point monitoring for perfect guarantee of compressed air quality
Standard version up to 17 bar for industrial compressed air plants
Integrated measuring chamber with directing throttle for fast and simple commissioning
Large, clear display, dew point display swappable between °C or °F
Adjustable limits with Hysteresis for early and main alarm
Simple operation over keyboard, clear operating procedure
Optical and acoustic alarm generator integrated in the device, switchable
Connection for external signal generator (acoustic and optical)
External, potential free relay switch output for early and main alarm
Serial interface RS 232 and RS 485
Analog output 4 ... 20 mA for –20 ... +40 °tpd
High grade, long term stable polymer sensor
5.1 Typical areas of application
Monitoring of compressed air for pneumatics and in the industry
Regulation of adsorption dryers
Monitoring of breathing gas for medical applications
Food industry, chemical applications
Plastic processing, drying systems

6 Function
If compressed air is not dried before feeding into the compressed air network, considerable
amount of condensate gets accumulated in the airline network and causes malfunctioning of
valves, pneumatic components and finally leads to loss of production. Hence, the pressure
dew point in compressed air system is a decisive parameter for air quality and should be
measured in every plant. In addition, there are applications, where the humid air can lead to
damages, for example, in compressed air lifted shafts or slides.
The pressure dew point instrument TPK 20 is an ideal device for monitoring compressed air
quality and give out an alarm at the right time before any damage occurs. The compact
device is meant for monitoring of cold and membrane dryers up to -20° dtp.
The device is provided with an integrated measuring chamber with protection filter and
diverting throttle and also a plug connection for NW 7.2 mm compressed air socket. The
power supply is through an enclosed plug-in type power supply unit. For installation of
measuring system, no intervention inthe compressed air network or electrical fitment workis
required. Alternatively, the measuring system can also be installed in the compressed air
pipeline, to avoid flushing air losses.
7 Functional scope
The device is provided with a display for on-the-spot display of measured dew point values.
The display can be switched between °C and °F units. The selected units are shown on the
display.
Through two potential free relay contacts (Normally open), the alarm signal is passed on to
an alarm unit or a higher level system. Alternatively, the relay contact can also be used for
regulation of dryers.
Two dew point based switching points and switching hysteresis can be adjusted over the soft
touch keyboard. The first switching point can be used, for example, as an early warning
alarm and the second switching point for main alarm. Alternatively, the first switching point
can also be used for regulation of the dryer. The overshooting of second alarm value is
additionally signalled over an LED at the display and also indicated on a acoustic signal
generator.
For connection to a super level regulation or monitoring system, the device has an analog
output 4 ... 20 mA which is scaled on the measuring range of -20 ... +40 °C tpd.
Additionally, a serial interface is also integrated, which enables connection to a PC. Direct
connection to the PC is possible with the RS232/USB connection cable available as
accessories and with this, recording of measurement data is possible. The software PCLOG
available as accessories enables graphic representation of measured values and simplifies
commissioning of larger plants.
The TPK 20 also has a built-in, internal alarm generator as well as an output to connect an
external alarm generator (optical and acoustic). An external alarm light is available as
accessories.

8 Mounting of the device
8.1 Safety instructions
The product should be installed and used only according to the intended application.
Fitment of the regulator and maintenance work should be carried out by only trained
personnel. Mounting and servicing operations should be carried out only after
switching off the voltage. The current safety regulations must be followed! All
activities in the compressed air network should be done in pressure less condition.
The device should be operated only with safe low voltage of 24 V DC. This also
applies to all external connections, for example, the relay outputs.
8.2 Application notes
Before mounting, the compressed air quality is to be checked at the assembly
location. In case of water or oil leakage, first the system is to be put in order. With
substantial water or oil exposure, the sensor can get damaged.
The compressed air withdrawal from the pipe must be done on the top side. The
device must be mounted above the compressed air line, so that in case of any failure,
the originated condensate does not flood the measuring chamber.
Use only suitable materials. The used materials must be steam diffusion sealed.
Hence, please do not use normal PUR-plastic hoses! For flexible connections, only
PTFE ("TEFLON “) is recommended as hose material. Up to –30 °C tpd, all metals are
suitable, in which stainless steel is to be preferred. Very long probe lines or
unnecessary joints are to be avoided.
All the components connected in series with the measuring probe should not show
any steam diffusion to the environment! Please only use high quality components,
e.g. ball valves with PTFE gaskets.
Please carefully seal all joints to the probe and the measuring chamber. However, do
not use anaerobic liquid sealing materials, because these can damage the sensor
element!
With time, heavy particle content deposit on the filter or the diverting throttle, which
leads to a delayed response behaviour. In critical cases, an additional micro filter
must be fitted before the instrument.
In case of undefined compressed air quality, use condensate separators or particle
filters. The additional components must be suitable for the application!
In EMV-critical environment, the measuring chamber should be electrically insulated
from the metal tube of the compressed air network. For this purpose, for example, a
double nipple of PTFE or polypropylene is suitable, which can be obtained from us on
enquiry.

8.3 Procedure for Installation
The installation is done in following steps:
Fastening of the device, if required
Connection at the compressed air network
Adjustment of diverting throttle, if required
Connection at the power supply
First time operation
Adjustment of switching point
Test and functional check
8.4 Mounting
If the device is to be operated in a portable manner or to be plugged to a standard coupling
as described below, no further mounting is required. In such a case, the lateral securing
collars can be removed.
In case of mounting on a machine, the device can be mounted on an even surface with the
help of enclosed mounting bracket. A drilling template is provided in the Appendix section of
these instructions.

9 Connection at the compressed air network
9.1 Direct stationery assembly at the compressed air line
In stationery applications, normally the device is directly installed after the dryer/filter, in
order to monitor the entire plant. However, the assembly can also take place at any position
in the subsequent distribution network, in order to monitor any sub unit or the operating air of
a particular machine.
In order to avoid unnecessary
consumption of air because of
diverted flushing air, the measuring
chamber should be preferably
installed with the probe into the
compressed air line.
In order to prevent accumulation of
condensation in the case of a fault,
the measuring chamber must be
vertically screwed onto the line
from above.
Extremely high flow velocities or
sudden change in pressure are to
be avoided, since the sensor
element can be damaged by it!
If a branch line is required for the
connection, then it should be only
some centimetres long, because
the response mode otherwise gets
worse, particularly at deep dew
point values. With longer branch
lines, the diverting throttle at the
measuring chamber must be
opened and a value of approx. 60
l/h must be adjusted..
Standing up, long branch lines
restrict the response mode or lead to wrong measured values.
For simplifying maintenance and modification, a ball valve can be connected in series. For
ball valves, only high-quality designs with Teflon gaskets are suitable!
9.2 Stationery assembly over hose
With the integrated measuring chamber with diverting throttle, alternatively the device can be
connected over a Teflon connection line to the compressed air supply. For correct functioning
and to guarantee the measuring accuracy, a regular flow must be available. The nominal flow
can be adjusted by the throttle. In order to avoid unnecessarily high flushing air losses, the
flow should be adjusted at nominal pressure to 60 l / h by means of a Flow meter.
Occasionally check whether the air is flowing out at the adjustment screw. With closed
throttle, the instrument shows too high value or raises an alarm.

9.3 Application of a pre-filter/water separator
According to the condition of the compressed air plant and the distribution network, it is
possible that unexpectedly dirt, condensate or oil also gets discharged at the measuring
point. In order to avoid damage to the measuring probe in such critical application areas, a
water separator with fine filter can also be connected before the device. The components
connected in series should not change the humidity content of air or unnecessarily worsen
the response behaviour. Suitable components can be obtained from us on enquiry.
9.4 Mounting examples
The device is suitable for a large number of application areas. With the flexible design of
measuring chamber, the device can be easily adapted for the intended application:
Connection to a quick coupling 7.2 mm NW:
This connection is fast and simple, can be done in
minutes without expensive installation.
Mounted with a plug nipple NW 7.2 mm below
with 3/8“ fitment threads.
The device can be directly plugged onto the
coupling without further fastening.
The diverting throttle is adjusted at approx. 60
l / h (factory setting during delivery).
Fixed connection over a compressed air line:
This connection is ideal with short distance to the
main line, since no flushed out air is used.
Mounted with a double nipple 3/8“ below,
other side matching with the pipe connection.
The device is directly mounted on the T-joint.
For immediate connection to a main line, the
diverting throttle is closed.
In case of larger connection length or branch
line, the throttle is adjusted to approx. 60 l / h

Connection over compressed air hose:
This connection variant is ideal, for example, if the
device is to be used as a portable unit, for
mounting in a machine or on a panel.
Mounted with thread 3/8“ below on 6/4 mm
hose.
The diverting throttle is adjusted at approx. 60
l / h for stationery applications, and for
portable quick measurement, it is adjusted at
approx. 240 l / h.
Note: Only PTFE-Hose should be used for the
connection!
9.5 Adjustment of diverting throttle
During delivery, the throttle is adjusted at 60 l / h nominal flow at 10 bar pressure. If the
throttle is not adjusted, normally no adjustment is necessary, if this flow rate is desired.
As per connection, the throttle can be closed in order to avoid flushing air losses. This is
done by fully rotating the Allen screw with the help of enclosed box spanner.
For portable applications, the nominal flow should be approx. 240 l/h. The throttle is opened
so much that the screw almost locks with the upper edge of the measuring chamber. The
diverting noise is clearly heard in this position. A fast response behaviour isreached with the
high nominal flow.
In order to again adjust the flow to 60 l for stationery applications, a flow meter is required,
which can be fitted over the screw with a gasket. The desired flow rate is adjusted by
reciprocal setting and checking till value is achieved.
The exact adjustment of defined quantity is specially important for stationery applications,
because it causes unnecessary high operating costs due to higher flow!
9.6 Connection of power supply
The device is to be operated with safe low voltage. A suitable plug-in power supply unit is
provided together. The power pack is plugged into the socket at the right side below the
extension plug.
An expensive electrical installation is avoided and the device is immediately ready for use.
The enclosed plug-in power pack with Euro plug is a high quality model with wide input
range and is suitable for voltage supply of 90-240 V. This power pack is suitable for complete
Europe wide application.
9.7 First time operation
After plugging the power pack, the device immediately comes into operation. There are no
further switches. Soon after switching on, the first measured values are readily displayed. If
the connection to the compressed air network has been just done for the first time, the
measurements shall still fall further. After some time, the values become stable. Depending
upon the system, the following values shall be adjusted:
In cold dryers, the value to be approx 0 ... 7 °C tdp
With an additional membrane dryer, value to be approx. -20 ... -10 °C
With an adsorption dryer, the value to be approx. -60 ... -30 °C

9.8 For the rarest of the cases...
If the device does not come into operation, then please check the following points:
Is there voltage in mains socket?
Is the mains plug correctly inserted
Is the socket of voltage supply sufficiently inserted inside?
Is the power pack supplying 24 V DC?
If you have checked all possible causes and still the malfunctioning is not resolved,
immediately contact our customer service. Do not open the device otherwise the war-
ranty claim becomes void!

10 Operation
General hints for description of operating procedure
All figures in the display, numerals and configuration shown are examples, which have been
used for the explanation and clarification of the transmitted contents. The actual display in
your device can vary according to the selected settings or ambient conditions.
10.1 View of device front and the control elements

10.2 Description of the Displays
View of Displays Function
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The upper display line is for the display
of measured values
The lower display line is for the display
of selected physical units
10.3 Operation of keys
The keys of control unit have the following basic functions:
Key Description Function
Settings-Key Setting the alarm and Hysteresis value
Enter key Accepting the new adjusted value as well as for Alarm
switch ON/OFF
Downward Decreasing the adjusted value
Upward Increasing the adjusted value

10.4 Switching on the device
In order to guarantee high long term stability of the dew point probes, the sensor element is
cyclically heated up. The heating takes place in every 13 h for a period of approx. 5 min.
each after which the sensor passively cools down again to ambient conditions.
During heating, the message "HEAT “ appears on the display and during passive cooling
down up to ambient temperature the message "COOL “ appears:
Status of the device View of display
The sensor element is getting heated up.
The device waits, until the sensor element is cooled down
again.
The heating up is re-started at each connection of the power supply and thereafter again in
every 13 hours. During the entire cycle, the last measurements are held up and no further
measurement are done, and therefore, during this time span, no alarm signal comes up in
the case of limit overshooting. Only after the heating/cooling cycle is completed, the device
further continues with the measurement and alarm evaluation.

10.5 Changing the alarm and Hysteresis value
The device is used for monitoring of dew points. The user can set a dew point limit value for
both early warning alarm and main alarm. In addition, the desired Hysteresis value for each
alarm value can also be adjusted.
Alternatively, the early alarm can also be used for other purposes, for example, for regulation
of a compressed air dryer. In such a case, the main alarm is available as message output.
Operation of keys View of display
By continued pressing of settings key, you can
go to the configuration of alarm and Hysteresis
value. The lower display line shows the
Alarm/Hysteresis value parameter being
adjusted (in this case “P1”) and the upper
display line shows the value being set.
By repeated pressing of the settings key, you
can switch between the individual setting
parameters ("P1/H1/P2/H2").
With the help of the Downward/Upward keys,
you can change the desired regulation value.
By short pressing of the key, the value can be
changed step-by-step in decimal numbers at
the right comma places. By long pressing of
the key, the values are changed in whole
numbers step-by-step.
With the "Enter" key, the new Alarm/ Hysteresis
values are taken up by the system and the
message "SET" appears as a confirmation of
the saving process. After this, the
measurements are displayed
Note: All individual values are to be separately
saved because every time the value just
changed before is only saved!
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The following table shows the assignment of the symbols shown in the lower display line for
the corresponding Regulation/Hysteresis values:
Displayed Symbol Associated Alarm / Hysteresis value
Dew point early warning alarm
Hysteresis value early warning alarm
Dew point main alarm
Hysteresis value Dew point

10.5.1 Switching ON/OFF of alarm generator and indicator LEDs
As per requirement, the alarm can also be completely turned off. The device is supplied with
alarm in switched on condition.
Operation of keys View of display
By keeping the Enter - key in pressed condition
till "Off" appears on the upper display line. The
alarm is now completely switched off.
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By again holding the Enter - key in pressed
condition, the alarm is switched on again. As a
result, the message "ON" appears on the upper
display line..
10.5.2 Behaviour during alarm
In case an early warning alarm or main alarm value is reached, the user is informed through
different warning signals :
Feedback of the Device View of display
On reaching the early warning alarm value :
The message "PRE" appears on the display at a gap of
approx. 3 seconds. The acoustic signal and the LEDs are not
activated during early warning alarm.
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On reaching the main alarm value :
The message "ALR" appears on the display at a gap of
approx. 3 seconds. If the alarm generator is switched on,
additionally an acoustic signal is given out and the warning
LEDs also blink.
If an external alarm light is connected to the device, it is also
activated.
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