Tecsis F9304, Руководство по эксплуатации, Страница: 19 / 28

Betriebsanleitung/Operating manual F9304
www.tecsis.de BD_BE 9005 a 19
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
individual 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 4-20mA output signal.
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 cell must be avoided if possible. One-sided or
local heating of the load cell 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).
5.2 Moisture and corrosion protection
Tropical climates and condensation are not a problem because the
load cells comply with protection class IP 67 in accordance to
EN 60529:1991+A1:2000 / IEC 529. The entire measuring spring is
made of stainless steel. The design of the accessory cable also
complies with protection class IP 67.
5.3 Deposits
Dust, dirt and other objects are not allowed to form deposits in such a
way that they create a force shunt to the measuring spring, which
would falsify the measuring signal.