SIEMENS
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Siemens D 83.1 · 2016
2
Motors with Explosion Protection
Orientation
■
Overview
(continued)
Hazardous areas
Note:
The installation regulations of VDE 0118 apply to firedamp
protection equipment. In mining, the areas are not subdivided
into Zones.
Note I:
Layers, deposits and accumulations of combustible dust must
be taken into consideration like any other possible cause of an
explosive atmosphere.
Note II:
Normal operation refers to the state in which the equipment is
used within its design parameters.
Zone acc. to
EN 60079-14
Explanations
Examples
Permissible electrical equipment
General
Motors
Gases, vapors and mist
Zone 0
Areas in which there is an
explosive gas atmosphere
constantly or over a long period
.
This normally only applies to the
internal space of containers or
apparatus.
Electrical equipment is only
permitted to be used in Zone 0
which is explicitly certified for
use in this zone.
Explosion-proof motors are not
permitted to be used here
whatever their type of
protection. Exceptions can only
be applied by the monitoring
authorities.
Zone 1
Areas in which it is to be
expected that a hazardous,
potentially explosive
atmosphere will only occur
occasionally
.
These include, for example:
Close proximity to Zone 0, the
internal space of equipment,
close proximity to
• Feed openings
• Filling and draining facilities
• Fragile apparatus or pipes
made of glass or ceramics,
etc.
Electrical equipment must be
explosion-proof in accordance
with one of the EN 60079-0
types of protection.
In Zone 1, explosion-proof
motors must be used that
have type of protection
"Explosion-proof enclosure",
"Increased safety" or
"Pressurized enclosure".
Zone 2
Areas in which it is to be
expected that a hazardous,
potentially explosive
atmosphere will occur
only rarely and then only
for a short period
.
These include, for example:
Areas surrounding Zones 0
and 1. Areas surrounding flange
connections with flat seals for
pipes in closed rooms.
Explosion-proof motors in
the type of protection
"Non-sparking" Ex nA
can be used in Zone 2.
Dust
Zone 20
Areas in which a potentially
explosive gaseous atmosphere
in the form of a cloud of
combustible dust is present
constantly over long periods,
or frequently
.
This normally only applies to the
internal space of apparatus
(mills, dryers, mixers, pipelines,
silos, etc.)
Electrical equipment is only
permitted to be used in Zone 20
which is explicitly certified for
use in this zone.
Explosion-proof motors are not
permitted to be used here.
Exceptions can only be applied
by the monitoring authorities.
Zone 21
Areas in which a potentially
explosive atmosphere in the
form a cloud of combustible
dust is occasionally
present
in normal operation
.
This zone may also include:
Areas in the immediate vicinity
of filling and draining stations
and areas in which dust
deposits build up that could
occasionally result in an
explosive mixture of
combustible dust and air during
normal operation
Motors with type of protection
"Explosion-proof enclosure",
"Increased safety" or "Non-
sparking" can be used in
Zone 21 provided that they
comply with IP6x degree of
protection, if they have an
EC/EU type-examination
certificate for Category 2D
and fulfill the requirements of
EN 60079-0 and EN 60079-31.
Zone 22
Areas in which a dangerous
explosive atmosphere in the
form of a cloud in the air
containing flammable dust does
not usually occur or occurs only
briefly during normal operation
.
These include, for example:
Areas in the vicinity of
apparatus when dust may be
expelled from unsealed areas
(e.g. mill rooms).
Motors without EU type-
examination certificate (with
EC Declaration of Conformity
of the manufacturer) are also
permitted to be used in
Zone 22. For non-conductive
dust, IP5x degree of protection
must be implemented as a
minimum and the requirements
of EN 60079-0 and
EN 60079-31 must be fulfilled.
In the case of conductive dust,
the requirements for Zone 21
apply.
© Siemens AG 2016