3.6.2
Area classification in the surroundings of the chamber
The VDL vacuum drying oven with the exception of the power plug is classified in category 3 in relation to
the environment . It may be installed in areas in which explosive atmospheres may occur on a rare and
temporary basis.
The chamber plug (power plug) is unprotected because it must be disconnected in case of an emergency
to completely separate the chamber from the power supply. therefore the electrical connection must be
established outside a zone.
Spreading of an explosive atmosphere, which may occur on a rare and temporary basis, to unprotected
areas must be reliably prevented by measures of the operator. In particular, this includes a sufficiently
dimensioned one technical ventilation according to country-specific regulations (TRBS 2152 Part 2 for
Germany).
Figure 10: Area classification in the surroundings of the chamber (schematic representation)
Occurrence of an explosive atmosphere:
occasionally (only in the chamber interior)
on a rare and temporary basis: in the ambiance of the chamber with the exception of the power plug
never (unprotected areas): Connection location of the power plug
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