5. Commissioning, operation
In pipelines or other measuring points, the temperature probe must
■
be positioned as far towards the flow as possible.
Errors in thermal conduction occur if the area where the temperature
■
is to be measured is so small, that the mass of the temperature
probe acts as thermal capacity. Errors in thermal conduction may
also occur if the insertion depth is insufficient, if the mounting fittings
are connected to a good thermal conductor (metal plate or similar)
and there is a considerable difference in temperature between the
measuring and mounting element temperatures.
Mount the indicator case free from vibration. If necessary, it is
■
possible to isolate the installation from the mounting point, e.g. by
installing a flexible connection line between the measuring point and
the thermometer and mounting the instrument on a suitable bracket.
Requirements for the installation point
If the line to the measuring instrument is not adequately stable, an
instrument mounting bracket should be used for fastening. If vibrations
cannot be avoided by means of suitable installation, filled instruments
should be used. The instruments should be protected against coarse
dirt and wide fluctuations in ambient temperature.
Permissible vibration load at the installation site
The instruments should always be installed in locations free from
vibration. If necessary, it is possible to isolate the instrument from the
mounting point, e.g. by installing a flexible connection line between the
measuring point and the instrument and mounting the instrument on a
suitable bracket.
If this is not possible, the following limit values must not be exceeded:
Frequency range < 150 Hz
Acceleration < 0.5 g (5 m/s
WIKA operating instructions model TGT73 (Ex)
)
2
EN
17