Betriebsanleitung/Operating manual
F5308/F53C8/F53S8
www.tecsis.de
BD_BE 991 d
31
4
Design and method of operation
4.1
Measuring element
Innovative manufacturing methods using the DMS principle have
recently been developed. Etched wire strain gauges are not used in this
case. The entire Wheatstone bridge with the necessary equalization re-
sistances and temperature compensation is realized using a thin-film
method on a metallic, pot-shaped body. The bridge circuitry of the sen-
sors is actively calibrated during the manufacturing process using laser
calibration. This thin-film sensor can now be inserted into an appropri-
ately shaped measuring spring with the aid of a laser welding method.
The thin-film sensor and the optional electronics are sealed against
moisture and dust.
4.2
Measuring procedure and output signal
The force acting in the measuring direction causes the measuring
spring to become elastically deformed and therefore also the welded-in
thin-film cell. This deformation generates a resistance change in the in-
dividual bridge resistors. If the measuring bridge is now supplied with a
feed voltage, a measuring signal that is proportional to the force occurs
at the bridge output. This signal can be output provided with the aid of
integrated amplifiers as standardised 4-20 mA, 0-10 V or as a CANo-
pen
®
output signal.
For the use in combination with the ELMS1 overload protection only
an opposing 4 ... 20 mA signal (redundant) is approved. Therefore
please note the instructions in the original operating manual for
ELMS1 overload protection.
5
Deployment location conditions
5.1
Ambient temperature
The temperature range of -20°C to +80°C that is specified in the data
sheet applies with regard to deployment. The specified error limits are
not guaranteed outside this temperature range. Temperature gradients
in the load pin must be avoided if possible. One-sided or local heating
of the load pin can cause large measuring errors.
The temperature errors specified in the data sheet always relate to
the entire measuring device up to the plug or the end of the cable
(including the integrated amplifier).
