Yamatake HGC303, Руководство пользователя

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Safety Yamatake Corporation
iv Model HGC303 - Heat Value Gas Chromatograph
2. Cable systems
2.1 Thermoplastic sheathed cables, thermosetting sheathed cables , or elastomeric
sheathed cables can be selected for fixed wiring in the hazardous areas.
2.2 Flameproof cable entry devices (cable glands) certified to comply with EN 50018
and appropriate to the type of cable employed, must be used for the connection of
cables to the apparatus.
3. Conduit systems
For conduit systems, relevant national standards or codes of practice are followed
prior to the following recommendations.
3.1 Screwed heavy gauge steel, solid drawn or seam welded conduit , or flexible
conduit for protection of cables in explosive atmospheres (see ISO 10807) can
be selected for fixed wiring in the hazardous areas.
3.2 Conduit must be threaded for connection to permit the full engagement of five
threads.
3.3 Either conduit entry devices or sealing devices such as stopping boxes are
provided at the wall of the apparatus enclosure to limit the pressure piling effect
and to prevent hot gases from entering the conduit system from the enclosure
containing a source of ignition.
Each type of both the devices must be certified
to comply with EN 50018.
3.4 The stopping boxes , if used, are filled with a compound which does not shrink
or setting and is impervious to, and unaffected by, chemicals found in the
hazardous area.
The depth of the compound in the stopping box is at least equal
to the internal diameter of the conduit, but in no case less than 10 mm.
3.5 When the conduit contains three or more non-seathed single or multi-core
cables , the total cross-sectional areas of cables, including insulation, are not more
than 40% of the cross-sectional area of the conduit.
4. Installation in explosive atmospheres caused by air / dust mixtures
4.1 Conduit or cable glands , if employed to connect cables to the apparatus, must be
selected and used in such a way that an IP6X protection (dust-tight) is guaranteed.
4.2 It is recommended to maintain the apparatus so that the dust layer will not exceed
a thickness of 5 mm .
~Note
Where the ignition temperature of a dust layer up to 5 mm thickness is
equal to, or higher than, the value that is obtained by adding 75K to the
maximum surface temperature of the enclosure “T... ° C” as marked on the
apparatus, the apparatus is incapable of causing ignition of the dust
layer. (T... ° C is based on the maximum ambient temperature)