Schaller LF-TD-TA Air Humidity Transmitter Instruction Manual
- August 31, 2024
- Schaller
Table of Contents
- LF-TD-TA Air Humidity Transmitter
- Specifications:
- Product Usage Instructions:
- 1. Introduction
- 2. For Your Safety
- 3. On Receipt of Your Device
- 4. Installation of the Transmitter
- 5. Technical Drawing LF-TD-TA
- 6. Adjustment Behaviour of the Sensor
- 7. Definition Relative Humidity
- 8. Cleaning and Maintenance
- 9. Checking the Calibration
- 10. Faults
LF-TD-TA Air Humidity Transmitter
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Specifications:
- Product: LF-TD-TA Air Humidity Transmitter
- Version: 1.4
- Main Components:
- Air humidity and temperature sensor
- Sensor tube
- Aluminium housing
- Connecting cable
- Mounting bracket
Product Usage Instructions:
1. Introduction
Before using the LF-TD-TA, read the operating manual
thoroughly.
2. For Your Safety
Ensure proper use of the device and adhere to safety guidelines
provided in the manual.
3. On Receipt of Your Device
Upon receiving your device, follow the steps outlined in the
manual for unpacking and verifying all components.
4. Installation of the Transmitter
-
4.1 Laying of the Supply Line: Ensure proper
placement of supply line or transmission line. -
4.2 Mounting: Securely mount the transmitter
according to the instructions provided. -
4.3 Pin Assignment: Follow the pin assignment
guidelines for correct installation. -
4.4 Wiring Diagram: Refer to the wiring
diagram for accurate connection.
5. Technical Drawing LF-TD-TA
Refer to the technical drawing for detailed visual guidance on
the device.
6. Adjustment Behaviour of the Sensor
Understand the sensor’s adjustment behavior for optimal
performance.
7. Definition Relative Humidity
Learn about the application range of relative humidity for
effective usage.
8. Cleaning and Maintenance
-
8.1 Care Instructions: Follow care
instructions to maintain device longevity. -
8.2 Cleaning: Regularly clean the device as
per the provided guidelines.
9. Checking the Calibration
-
9.1 Assembling Calibration Equipment: Gather
necessary equipment for calibration. -
9.2 Determining Deviation: Follow steps to
determine calibration deviation.
10. Faults
Refer to the manual for troubleshooting guidance in case of
faults.
Frequently Asked Questions (FAQ):
Q: What should I do if the device shows inaccurate
readings?
A: If you encounter inaccurate readings, first check the
calibration and sensor adjustment. If issues persist, contact
customer service for further assistance.
Q: How often should I clean the device?
A: Regular cleaning is recommended as per the care instructions
provided in the manual. Depending on usage conditions, cleaning may
be required periodically.
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Moisture meter
Operating Manual LF-TD-TA
Air humidity transmitter series
78,0°F | 6,16% | 456kg/m3 | -27,3td | 0,64aw | 51,9%r.H. | 14,8%abs | 100,4g/m2 | 09m/s | 4,90Ugl | 1
Version 1.4
Always read this operating manual before using the LF-TD-TA!
LF-TD-TA Operating Manual
Your LF-TD-TA at a glance
The main unit 1
2
5 3
4
No. Name 1 Air humidity and temperature sensor 2 Sensor tube 3 Aluminium
housing 4 Connecting cable 5 Mounting bracket
Page 2
Table of contents
Your LF-TD-TA at a glance 2
The main unit ……………………………………………………………………………………………………2
1
Introduction 5
1.1
Information about this operating manual ……………………………………………….5
1.2
Limitation of liability ……………………………………………………………………………5
1.3
Symbols used in this manual ………………………………………………………………..6
1.4
Customer service ……………………………………………………………………………….6
2
For your safety 7
2.1
Proper use ………………………………………………………………………………………..7
2.2
Improper use …………………………………………………………………………………….7
2.3
User qualifications ………………………………………………………………………………7
2.4
General safety information …………………………………………………………………..8
2.5
Warranty ………………………………………………………………………………………….8
3
On receipt of your device 8
3.1
Taking the device out of its packaging ……………………………………………………8
3.2
Making sure that all of the components have been included ……………………..8
3.2.1
Scope of supply …………………………………………………………………………………9
4
Installation of the transmitter 9
4.1
Laying of the supply line or transmission line …………………………………………..9
4.2
Mounting the transmitter …………………………………………………………………….9
4.3
Pin assignment …………………………………………………………………………………11
4.4
Wiring diagram ………………………………………………………………………………..11
5
Technical drawing LF-TD-TA 12
6
Adjustment behaviour of the sensor 12
Definition relative humidity 13
7.1
Application range …………………………………………………………………………….13
8
Cleaning and maintenance 14
8.1
Care instructions ………………………………………………………………………………14
8.2
Cleaning the device ………………………………………………………………………….14
9
Checking the calibration 15
9.1
Assembling the calibration equipment …………………………………………………15
9.2
Determining the deviation ………………………………………………………………….16
10
Faults 17
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LF-TD-TA Operating Manual
11
Storage and disposal 18
11.1
Storing the device …………………………………………………………………………….18
11.2
Disposing of the device ……………………………………………………………………..18
12
Device information 19
12.1
EC declaration of conformity ………………………………………………………………19
12.2
Technical data ………………………………………………………………………………….23
Page 4
1. Introduction
1.1 Information about this operating manual
This operating manual is designed to enable you to use the LF-TD-TA safely and
effectively. It is part of the device, has to be stored nearby and must be
easily accessible to users at all times. All users are required to carefully
read and make sure that they have understood this operating manual before
using the LF-TD-TA. All of the safety and operating instructions detailed in
this manual have to be observed to ensure the safety of the device.
1.2 Limitation of liability
All of the information and instructions provided in this operating manual have
been compiled on the basis of the current standards and regulations, the state
of the art, and the extensive expertise and experience of Schaller Messtechnik
GmbH. Schaller Messtechnik GmbH does not accept any liability for damage
associated with the following, which also voids the warranty:
· Non-observance of this operating manual · Improper use · Inadequately
qualified users · Unauthorised modifications · Technical changes · Use of
unapproved spare parts This fast measuring procedure can be affected by a
range of different factors. We, as the manufacturer, do not accept any
liability for any incorrect measurements and associated consequential damage.
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LF-TD-TA Operating Manual
1.3 Symbols used in this manual
All of the safety information provided in this manual is shown with a
corresponding symbol.
ATTENTION
It is essential to observe this warning. Non-compliance can lead to damage to
property or equipment.
i Information
This symbol indicates important information that enables users to use the
device more efficiently and cost-effectively.
1.4 Customer service
For technical advice, please contact our customer service department at:
Schaller Messtechnik GmbH Max-Schaller-Straße 99 A – 8181 St.Ruprecht an der
Raab Telephone: +43 (0)3178 28899 Fax: +43 (0)3178 28899 – 901 E-mail:
info@humimeter.com Internet: www.humimeter.com © Schaller Messtechnik GmbH
2024
i Information
Your purchased measuring instrument can be calibrated, and the adjustment
checked by using suitable test ampoules / calibration ampoules. For this
purpose, use only the calibration solutions distributed by Schaller
Messtechnik Gmbh. You can download a calibration certificate for your test
ampoules / calibration ampoules with the batch number printed on the ampoul
fromhttps://www. humimeter.com/certificates/.
Page 6
2. For your safety
The device complies with the following European directives: · Restriction of
Hazardous Substances in Electrical and Electronic Equipment (RoHS) ·
Electromagnetic compatibility (EMC)
The device corresponds to state-of-the-art technology. However, it is still
associated with a number of residual hazards. These hazards can be avoided
through strict observance of our safety information.
2.1 Proper use
· Transducer for measuring and transmitting relative humidity and temperature
in fixed installation
· The sensor technology used makes it possible to detect even small
fluctuations in humidity and their tendencies quickly and reliably so that
preventive actions can be taken.
· For some applications (e.g. installation in sewage pipes) it is necessary to
use a remote measuring probe for the reason of temperature adjustment.
2.2 Improper use
· The device must not be used in ATEX.
2.3 User qualifications
The device must only be operated by people who can be expected to reliably
take the measurements. The device must not be operated by people whose
reaction times may be slowed due to, e.g. the use of drugs, alcohol or
medication. All persons using this device must have read, understood and
follow the instructions provided in the operating manual.
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LF-TD-TA Operating Manual
2.4 General safety information
The following safety information has to be observed at all times to avoid
damage to objects and injury to people:
· In case of damages or loose parts on the device, contact Schaller
Messtechnik GmbH or your dealer.
All of the device’s technical features have been inspected and tested before
delivery. Every device has a serial number. Do not remove the tag with the
serial number.
2.5 Warranty
The warranty does not apply to: · Damage resulting from non-observance of the
operating manual · Damage resulting from third-party interventions · Products
that have been used improperly or modified without authorisation · Products
with missing or damaged warranty seals · Damage resulting from force majeure,
natural disasters, etc. · Damage from improper cleaning
3. On receipt of your device
3.1 Taking the device out of its packaging
· Take the device out of its packaging. · Next, make sure that it is not
damaged and that no parts are missing.
3.2 Making sure that all of the components have been included
Make sure that all of the components have been included by checking the
package contents against the following list:
Page 8
3.2.1 Scope of supply
· LF-TD-TA · Connecting cable of 1.9 m length · Operating manual
Optional accessories (not all available for LF-TD-TA):
· Display for LF-TD · Display with keypad for LF-TD · Relay output for
moisture for LF-TD · Mounting bracket for LF-TD · Drip-catcher for LF-TD ·
RS232 interface – described in a separate operating manual · USB interface –
described in a separate operating manual · Custom-made design – flat rate for
air humidity transmitter series per order · Factory calibration certificate,
calibration equipment, certified calibration am-
poules and reference devices – for continuous monitoring
4. Installation of the transmitter
4.1 Laying of the supply line or transmission line
· The cable must not be laid in the area of interference fields. · Do not
operate the transmitter in the area of electromagnetic interference
fields. · The permissible cross-sections for the installation must be
observed. · The cable length must be kept as short as possible. » If an
extension of the cable is required, the cross-section of the extension must
not be below 0.25 mm2. · If the electronics housing and the display
electronics are grounded, an appropri-
ate equipotential bonding conductor must be provided.
4.2 Mounting the transmitter
· The measuring probe must be positioned at a representative location. » Avoid
positions of draught and unnatural temperature fluctuations. » Do not expose
the device to direct sunlight.
· If the sensor tube is twisted, the tightness is no longer guaranteed.
Page 9
LF-TD-TA Operating Manual · When there is a possibility of condensation,
position the sensor probe slightly upwards (approx. 10 degrees angle). » The
condensation water can then flow away from the sensor probe towards the
housing or cable and drain off. » If it is impossible to place the unit at an
upward angle, a drip nose (optional accessory) must be installed. ·
Installation inside an air duct (or at mounting locations where temperature
differences between sensor probe and sensor housing may occur: » The sensor
must be inserted fully into the opening until it stops, to avoid a temperature
drop along the sensor tube. See sketch:
example for integration
Page 10
4.3 Pin assignment
Cable color White
Brown Green Yellow Grey Purple
Pin no. Function
1
2 3 4 5 Housing
Power supply V- (0 VDC) Ground current output Power supply V+ (12 to 29 VDC) Analogue output humidity 4 – 20 mA n.c. Analogue output temperature 4 – 20 mA Equipotential bonding GND
ATTENTION
Damage to the electronics due to incorrect connected cables Incorrect
connected cables can lead to severe damage to the electronics. Connect all
cables correctly.
4.4 Wiring diagram
Power supply Brown
V+ (24VDC) V- (0VDC) White
Evaluation unit (PLC , …)
A Green
A
Grey
Purple
Transmitter LF-TD 60
Power supply V+ (24VDC) Power supply V- (0VDC) Analog output humidity 4-20mA
Analog output temperature 4-20mA Potential equalisation GND
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LF-TD-TA Operating Manual
5. Technical drawing LF-TD-TA
6. Adjustment behaviour of the sensor
In humidity and temperature measurement, several parameters are responsible
for the adjustment behaviour (time until the actual measured value is
displayed). The parameter responsible for the highest measuring error is a
temperature discrepancy between the sensor resp. the whole measuring
instrument and the material being measured resp. the air. Therefore, let the
device adjust until the displayed temperature corresponds to the actual
temperature. The graph below shows how long it takes to adjust from 20 °C to
30 °C.
Page 12
To demonstrate the importance of temperature adjustment, the table below shows the measuring errors due to a temperature difference between the measuring instrument and the material being measured of only 1 °C / 1.8 °F, at different ambient temperatures.
10 % r.h. 50 % r.h. 90 % r.h.
10 °C (50 °F)
+/- 0.7 % +/- 3.5 % +/- 6.3 %
20 °C (68 °F)
+/- 0.6 % +/- 3.2 % +/- 5.7 %
30 °C (86 °F)
+/- 0.6 % +/- 3.0 % +/- 5.4 %
At room temperature (20 °C / 68 °F) and an assumed humidity value of 50 % relative humidity a temperature difference between the measuring sensor and the material being measured of 1 °C / 1.8 °F causes a measurement error of 3.2 % relative humidity. A temperature difference of 3 °C / 5.4 °F would cause a measurement error of more than 10 % relative humidity.
7. Definition relative humidity
Indicates the relationship between the current water vapour pressure and the
maximum possible, the so-called saturation vapour pressure.
The relative humidity shows the degree the air is saturated with water vapour.
Examples:
50% relative humidity: At the current temperature and pressure, the air is
half saturated with water vapour. 100% relative humidity means that the air is
totally saturated with water vapour. If the air has more than 100% humidity,
the excessive humidity would condense or precipitate as mist.
7.1 Application range
Within the normal application range (normal range) the accuracy of the device
is as indicated. A long-term application beyond the normal application range
(max. range), particularly at an air humidity of more than 80%, can lead to
higher measuring errors. Back in the normal application range, the sensor will
return to the indicated accuracy automatically.
LF-TD 60 LF-TD 90 Profinet LF-TD 120
Page 13
LF-TD-TA Operating Manual
8. Cleaning and maintenance
Regularly cleaning and maintaining the device will ensure that it will have a
long service life and stay in good condition.
8.1 Care instructions
· Do not leave the device out in the rain. · Do not immerse the sensor in
water. · Do not expose the device to extreme temperatures. · Protect the
device from strong mechanical shocks and loads.
8.2 Cleaning the device
ATTENTION
Do not clean with fluids Water or cleaning fluid getting inside the device can
destroy the device. Only clean with dry materials. Aluminium housing and
sensor tube Clean the aluminium housing and the sensor tube with a dry cloth.
Air humidity and temperature sensor The air humidity and temperature sensor
cannot be cleaned. In case of a polluted sensor please contact your dealer.
Page 14
9. Checking the calibration
To do so: Calibration equipment (art.no.10006) and calibration ampoules (humidity standards art.no. 10005) required. The device, the calibration equipment and the humidity standards must have a temperature between 20.0 °C and 26.0 °C. It is recommended to store the device, the calibration equipment and the calibration ampoules in a room with little temperature fluctuation for 24 hours.
9.1 Assembling the calibration equipment
1. Place the sealing ring over the threads of the
1
lower part like shown in figure 1.
2. Place the textile pad into the lower part (figure
- and carefully pour the humidity standard onto
the pad, beginning with the humidity standard
of 35 % relative humidity.
2
3
3. Carefully place the upper part onto the lower part (figure 3) and tighten the upper part clockwise.
» Recommendation: Keep the lower part on the
4
table while screwing on the upper part.
» If necessary, only lift the calibration equipment straight up and do not tilt or turn it over.
4. Loosen the fixing nut counterclockwise until the sensor tube of the measuring device can be inserted without excessive pressure.
5. Now carefully push the sensor tube of the measuring device into the upper part until it stops (figure 4).
6. Secure the calibration equipment on the sensor tube by tightening the previously loosened fixing nut.
» Make sure to lift the device with the calibration equipment only straight up
and do not tip or turn it over Otherwise you could damage the sensor.
» Do not remove the calibration equipment from the sensor tube until
specifically indicated otherwise.
» Place a distance holder under the device so that the device and the
calibration equipment lay horizontally on the table.
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LF-TD-TA Operating Manual
ATTENTION
Damage to the sensor By tilting or turning the device with mounted calibration equipment the sensor can be destroyed. Only lift the device with mounted calibration equipment straight up.
9.2 Determining the deviation
1. Let the sensor adjust to the humidity standard for at least 2 hours.
2. Then note down the measured relative humidity and temperature.
3. At ideal temperature conditions (device, calibration equipment and
humidity standard have a temperature of 23 °C), the value printed on the
humidity standard can be used as reference value.
4. In case of deviation from the factory temperature (23.0 °C), the real
humidity value must first be determined according to the table below.
Temperature
20 °C 21 °C 22 °C 23 °C 24 °C 25 °C 26 °C
Humidity standards
35 % 50 % 80 %
34.6 % 34.8 % 34.9 % 35.0 % 35.1 % 35.2 % 35.4 %
49.8 % 49.8 % 49.9 % 50.0 % 50.1 % 50.2 % 50.2 %
79.9 % 80.0 % 80.0 % 80.0 % 80.0 % 80.0 % 80.1 %
5. Note down the real humidity value.
6. Compare the noted displayed measuring value with the real humidity value.
» If the deviation revealed is below 1.5 % relative humidity, it is not
recommended to recalibrate.
» If the deviation revealed is more than 1.5 % relative humidity, please
contact your dealer.
7. Now remove the calibration equipment from the sensor tube and repeat the
procedure from “9.1 Assembling the calibration equipment”, optionally with the
humidity standard 50 % relative humidity or the humidity standard 80 %
relative humidity.
Page 16
10. Faults
If the measures listed below fail to remedy any faults or if the device has faults not listed here, please contact Schaller Messtechnik GmbH.
Fault Measuring error
Cause
Remedy
The temperature is outside the operating temperature: lower than -20 °C or higher than +60 °C
Only use the device in temperatures between -20 °C and +60 °C.
Measurement error due to too short temperature adjustment time
Let the device adjust to the surroundings (see “6. Adjustment behaviour of the sensor”).
Sources of heat or cold that do Reposition your device at a
not correspond to the surroun- location that is representa-
ding temperature
tive for the room climate.
Dripping water or sprayed water
Direct contact of the sensor with dripping or sprayed water will destroy it.
Irreversible damage of the sen- Please contact your dealer. sor due to aggressive gases
Condensation caused by a change in temperature
Condensation on the sensor interferes with the calibration. Let the device adjust to the surrounding temperature.
Polluted air humidity and tem- Please contact your dealer. perature sensor
Foreign particles on the sensor Please contact your dealer.
Page 17
LF-TD-TA Operating Manual
11. Storage and disposal
11.1 Storing the device
The device must be stored as follows: · Do not store outdoors. · Store in a
dry and dust-free place. · Protect the device from sunlight. · Avoid
mechanical shocks/loads. · Storage temperature: -20 °C to +60 °C
11.2 Disposing of the device
Devices marked with this symbol are subject to Directive 2012/19/ EU of the
European Parliament and of the Council of 4 July 2012 on waste electrical and
electronic equipment (WEEE). If the device is being operated outside the
European Union, the national regulations on the disposal of such devices that
apply in the country of use must be observed. Electronic devices must not be
disposed of as domestic waste. The device must be disposed of appropriately
using appropriate collection systems.
Page 18
12. Device information
12.1 EC declaration of conformity
___ KONFORMITÄTSERKLÄRUNG DECLARATION OF CONFORMITY
Name/ Adresse des Herstellers: Name/ address of manufacturer:
Schaller Messtechnik GmbH Max-Schaller-Straße 99 A 8181 St. Ruprecht
Produktbezeichnung: Product designation: Typenbezeichnung:
Type designation: Produktbeschreibung: Product description
Schaller
LF-TD-A ; LF-TD 60 ; LF-TD 90 ; LF-TD 120 ; LF-TD 150; LFTD 180 ; LF-TD-E ;
LF-TD-U ; LF-TD-ER ; LF-TD Profinet ; LF-TD-H
Messgerät zur Bestimmung der rel. Feuchte und abgeleiteter Messgrößen
Measuring instrument for determining relative humidity and derived measured
variables
Das bezeichnete Produkt erfüllt die Bestimmungen der Richtlinien: The designated product is in conformity with the European directives:
EMV – Richtlinie 2014/30/EC RoHS – Richtlinie 2011/65/EG
EMC Directive 2014/30/EU RoHS-Directive 2011/65/EU
Die Übereinstimmung des bezeichneten Produktes mit den Bestimmungen der
Richtlinien wird durch die vollständige Einhaltung folgender Normen
nachgewiesen:
Full compliance with the standards listed below proves the conformity of the
designated product with the provisions of the above-mentioned EC Directives:
EN 613261:2013
EN IEC 63000:2019-05 ersetzt / replaced EN 50581:2012
Elektrische Mess-, Steuer-, Regel- und Laborgeräte – EMV-Anforderungen
Electrical equipment for measurement, control, and laboratory use EMC
requirements
Technische Dokumentation zur Beurteilung von Elektro- und Elektronikgeräten
hinsichtlich der Beschränkung gefährliche Stoffe. Technical documentation for
the assessment of electrical and electronic products with respect to the
restriction of hazardous substances.
Page 19
LF-TD-TA Operating Manual
Für das angeführte Produkt ist eine vollständige Dokumentation mit
Betriebsanleitung in Originalfassung vorhanden.
For the mentioned product a complete documentation with manual of instruction
in original version is available.
Bei Änderungen, die nicht vom Hersteller spezifiziert sind, verliert diese
Konformitätserklärung die Gültigkeit.
In case of any changes not agreed upon with the manufacturer, this declaration
of conformity loses its validity.
St. Ruprecht a.d. Raab, 31.07.2022
…………………………………………………..
Bernhard Maunz Rechtsverbindliche Unterschrift des Ausstellers Legal binding
signature of the issuer
Page 20
___ DECLARATION OF CONFORMITY
Name/ address of manufacturer:
Schaller Messtechnik GmbH Max-Schaller-Straße 99 A 8181 St. Ruprecht
Product designation: Type designation:
Product description:
Schaller
LF-TD-A ; LF-TD 60 ; LF-TD 90 ; LF-TD 120 ; LF-TD 150; LFTD 180 ; LF-TD-E ;
LF-TD-U ; LF-TD-ER ; LF-TD Profinet ; LF-TD-H
Measuring instrument for determining relative humidity and derived measured
variables
The designated product is in conformity with the following directives:
· Electromagnetic Compatibility Regulations 2016 Great Britain
· RoHS-Directive 2011/65/EU Directive on the restriction of the use of certain
hazardous substances in electrical and electronic equipment
Full compliance with the standards listed below proves the conformity of the designated product with the provisions of the above-mentioned Directives:
EN 613261:2013
EN IEC 63000:2019-05 replaced EN 50581:2012
Electrical equipment for measurement, control, and laboratory use EMC
requirements
Technical documentation for the assessment of electrical and electronic
products with respect to the restriction of hazardous substances.
Page 21
LF-TD-TA Operating Manual
For the mentioned product, a complete documentation with manual of instruction
in original version is available.
In case of any changes not agreed upon with the manufacturer, this declaration
of conformity loses its validity.
St. Ruprecht a.d. Raab, 31.07.2022
…………………………………………………..
Bernhard Maunz Legal binding signature of the issuer
Page 22
12.2 Technical data
Measuring range rel. air humidity
0 % to 100 %
Calibration rel. air humidity 10 % to 90 %
Accuracy rel. air humidity
+/- 3.0 % (at 25 °C)
Measuring range temperature -20 °C to +60 °C
Calibration temperature
+10 °C to +60 °C
Accuracy temperature
+/- 0.6 °C (at 25 °C) / +/- 1.0°F (at 77 °F)
Operating temperature
-20 °C to +60 °C (sensor tube) -20 °C to +85 °C (electronics)
Outputs
rel. air humidity (4 – 20 mA) -Scaling (0 % to 100 %) Temperature (4 – 20 mA) -Scaling (-20 °C to +60 °C) Working resistance < 500 Ohm (UB 24 V)
Temperature compensation Automatic
Power supply
12 to 29 VDC
Current consumption
18 mA (without interfaces, display or any bus systems)
Electrical connection
Connection cable 1.9 m
Housing dimensions
70 x 32 x 120 mm
Housing material
Anodised aluminium
Sensor tube dimensions
12 x 130 mm
Sensor tube material
Stainless steel (front), anodised alu (back)
Sensor cap
Stainless steel sinter cap
IP rating electronics housing IP 54
Page 23
Schaller Messtechnik develops, produces and sells professional moisture meters
and turnkey solutions.
Schaller Messtechnik GmbH Max-Schaller-Straße 99, A – 8181 St. Ruprecht an der
Raab Tel +43 (0)3178 – 28899 , Fax +43 (0)3178 – 28899 – 901
info@humimeter.com, www.humimeter.com
References
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