WIKA GDM-100-TI Betriebsanleitung Seite 13

5. Commissioning, operation
5.1.2 Installation
With transport or storage, it can occur that gas density monitors warm up or cool down
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and this results in pointer movements. These pointer movements are caused by the
compensation system. To make sure that the instruments have adapted sufficiently to
ambient temperature, at least 2 hours at 20 °C must be allowed for adaptation to the
temperature. Then, in the depressurised state, the pointer will sit within the tolerance
bar.
Corresponding to the general technical rules for pressure gauges (e.g. EN 837-2
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"Selection and installation recommendations for pressure gauges") when screwing in
the instrument, the force required to do this must not be applied through the case, but
only through the spanner flats provided for this purpose and using a suitable tool.
When screwing in, do not tilt the threads.
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For parallel threads, use flat gaskets, lens-type sealing rings or WIKA profile sealings
at the sealing face . With tapered threads (e.g. NPT threads), sealing is made in the
threads , using a suitable sealing material (EN 837-2).
The tightening torque depends on the sealing used. In order to orientate the measuring
instrument so that it can be read as well as possible, a connection with LH-RH union or
union nut should be used. When a blow-out device is fitted to an instrument, it must be
protected against being blocked by debris and dirt.
5.1.3 Temperature load
The installation of the instrument should be made in such a way that the permissible
operating temperature, also considering the effects of convection and thermal radiation,
neither exceeds nor falls below the permissible limits.
The influence of temperature on the indication and measurement accuracy must be
observed.
5.2 Electrical mounting of the gas density monitor
The instrument must be grounded via the process connection.
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For cable outlets, make sure that no moisture enters at the cable end.
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Select a cable diameter that matches the cable bushing of the connector. Make sure
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that the cable gland of the mounted plug has a tight fit and that the seals are present
and undamaged. Tighten the threaded connection and check that the sealing is
correctly seated, in order to ensure the ingress protection.
Connection details and switching functions are given on the product label. Connec-
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tion terminals and ground terminal are appropriately marked.
WIKA operating instructions, models GDM-100-TI, GDM-100-TA
Spanner flats
Sealing face

Sealing in the thread

EN
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