AW / AK / BW / BK / BZ Sensors for Humidity and Temperature0 pages

Galltec Mess- und Regeltechnik GmbHt

D-71145 Bondorf . Germany t
Tel. +49 (0)7457-9453-0 . Fax +49 (0)7457-3758 t
E-Mail: sensoren@galltec.de . Internet:www.galltec-mela.det

MELA Sensortechnik GmbH

D-07987 Mohlsdorf-Teichwolframsdorf . Germany
Tel. +49(0)3661-62704-0 . Fax +49(0)3661-62704-20
E-mail:mela@melasensor.de . Internet: www.galltec-mela.de

A and B Series
Sensors for Humidity and Temperature

for industrial applications from -80...200°C and up to 25 bar
AK...
with SVKA.0E...
duct version
up to 150° C

AW...
with SVKA.00...
wall moumting

AW...
with SZKA.0H...
(sensor part
from -80...200° C)

Galltec+Mela® sensors in the A series combine the digital
measured value processing with the advantages of our robust
industrial sensors which can be used at temperatures up to
-80...200°C resp. at pressures up to 25 bar and are ideally
suited for demanding industrial applications.
The A series with exchangeable sensor part consist of a
calibrated sensor part with 4-pin plug and a transmitter with
analog output. Sensor part and transmitter can be combined
and matched with each other, according to the physical and
mechanical requirements.
The measured humidity and temperature values are calculated in the calibrated sensor part with the calibration values stored there, and are passed on as digital measurement values.
The sensor parts are either firmly connected to the transmitter or are exchangeable via plug-in connection and can be
readjusted on site using buttons and LED. They can also be
factory-calibrated and readjusted using software.

Description of the Sensor
The sensors of the A and B series with integrated hx processor
measure humidity by means of a humidity-dependant condenser.
The capacitive Mela® humidity measuring element, produced using
thinfilm technology, consists of a base plate, on which the electrodes are housed and a hygroscopic polymer layer above it. The
hygroscopic polymer layer absorbs water molecules from the medium to be measured (air) or releases them, thereby altering the
capacity of the condenser.
The transmitters with the hx processor use the values of the relative humidity and the temperature to calculate the dew point temperature, the enthalpy, the mixing ratio, the absolute humidity or
the wet-bulb temperature, in accordance with the laws of physics2).
The values are emitted at two analogue outputs with the standardised signals 0….1VDC or 0 ….10VDC or 4 ….20mA. The outputs
can be configured differently and are defined using the software.
Further measuring ranges on request.
The sensor parts and transmitters of the B series are firmly connected. In addition, the installation of a passive temperature element is possible (e.g. Pt100). All further technical features correspond to the ones of the A series.
The scope of delivery includes the sintered high-grade steel filter
ZE13. If a better dynamics should be required, we recommend to
use the filter type ZE04 together with a PTFE filter which protects
the humidity sensing element directly. We recommend to do so in
particular at low air speeds and also its increased service life, even
under more challenging operating conditions (pollutant impact or
permanent humidity > 95 %rh). The use of different filters is not
possible. The sensors are designed for unpressurised systems
(except the ...HD... version), the measurement medium is nonaggressive air.
Please consult „application instructions for the sensing elements“ (product info sheet no. A 1) or check with the manufacturer
for further information which you need to bear in mind when using
humidity sensors with capacitive sensing elements.
2)t

www.galltec-mela.de

The accuracy of the calculated values depends on both the operating point
in accordance with the hx diagram and on the primary values measured.

Galltec+Mela
A and B Series
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