WIKA GDT-20 Mode D'emploi page 34

5. Commissioning, operation
EN
5.1.2 Installation using an adapter and measuring chambers
The process connections of the available adapters and/or measuring chambers are to
be properly sealed and connected to the measuring location.
5.1.3 Installing the instrument
When screwing in the instrument, the force required to do this
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must not be applied through the case, but only through the
spanner flats provided for this purpose and using a suitable tool.
The torque should maximally be 60 Nm when screwing it in.
When screwing in, do not cross the threads.
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5.2 Electrical mounting
5.2.1 Connection assembly
Use a cable consisting of shielded twisted pair data lines with suitable characteristics
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for the particular operating conditions.
Select a cable diameter that matches the cable bushing of the connector. Make sure that
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the cable gland of the mounted connector has a tight fit and that the seals are present
and undamaged. Tighten the threaded connection and check that the seal is correctly
seated, in order to ensure the ingress protection.
Make sure that no moisture enters at the cable end.
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By installing a model GDHT-20, a small quantity of humidity from the
atmosphere inevitably enters the measuring cell. The correct measuring
results with non-flowing, very dry gas compartments will only become
attained over time (depending on the particular application, this may take
several days).
The measuring location should preferably be positioned directly at the gas
compartment. Measurement at the end of measuring lines prevents optimal
results (unwanted temperature differences and no humidity balance to the
main tank).
CAUTION!
If the model GDHT-20 is delivered with an adapter or measuring chamber,
it is completely mounted and tested for leak tightness ex-works. Dismoun-
ting compromises the leak tightness of the measuring assembly and
renders it unserviceable!
WARNING!
The instrument shield does not act as a protective conductor for protection
of personnel, rather as a functional ground in order to shield the instru-
ment from electromagnetic fields.
WIKA operating instructions transmitter, models GDT-20 and GDHT-20