5. Commissioning, operation
Installation with
open-ended spanner
If possible, the entire length of the stem should be exposed to the
■
temperature being measured. However, at least the length of the
active part that corresponds to the length of the gas expansion
vessel (active length).
In pipelines or other measuring points, the temperature probe must
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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
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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.
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 models 73, 74, 75
2
)
After installation, set the vent valve (if available)
from CLOSE to OPEN.
EN
13