HBK HBM CFT+ Montageanleitung Seite 13

6 CONDITIONS ON SITE
CFT+ force transducers are made of stainless materials. Protect the transducer neverthe­
less from weather conditions such as rain, snow, ice, and salt water.
6.1 Ambient temperature
The temperature has very little effect on the output signal. To obtain optimum measure­
ment results, comply with the nominal (rated) temperature range.
All series CFT+ sensors are mechanically pre-stressed with the corresponding parts. The
pre-stress force depends on the modulus of elasticity of the materials being used. Since
the modulus of elasticity varies with the temperature, the pre-stress force also varies with
the temperature. The sensor forwards this variation as a measurement signal to the
charge amplifier. If you want to perform quasi-static measurements (for example adjust­
ing measurement chains), we recommend bringing the measurement chain to a uniform
and constant temperature.
Please be aware that the drift of a piezoelectric measurement chain may increase at a
higher temperature, as the mobility of the charge carriers rises with the temperature.
6.2 Moisture and corrosion protection
CFT+ series force transducers meet the conditions of degree of protection IP65 in accor­
dance with EN 60529, if a connection cable is connected.
With stainless steel force transducers, please note that acids and all materials which re­
lease ions will also attack stainless steels and their seam welds. Any resulting corrosion
could cause the force transducer to fail. In this case, appropriate means of protection
must be provided. Force transducers should be protected in general against substances
that attack stainless steels.
CFT+
CONDITIONS ON SITE
11