DURAG D-LX 201 User Manual

3 | Explosion protection
D-LX 201/721
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3.5 EPL Equipment Protection Level
The inclusion of Equipment Protection Levels (EPLs) for explosion protected operating
equipment represents a new alternative to the concept of zones for the choice of
devices. It is mentioned here for information purposes. The risk of internal ignition can
be assessed in a better and more flexible way by means of a risk assessment. Each
zone can be assigned a precise equipment protection level without an additional risk
assessment.
The following assignments of DURAG devices are important:
Zone EPL
Zone 1 Gb
Zone 2 Gc
Zone 21 Db
Zone 22 Dc
Table3.2: EPL of DURAG devices
3.6 Ignition protection categories
The highest degree of safety when using flammable substances is achieved if the de-
velopment of a potentially explosive atmosphere is prevented (primary explosion pro-
tection).
In areas where potentially explosive atmospheres need to be expected despite all ne-
cessary measures being taken, only explosion-protected operating materials may be
used.
The ignition protection type refers to different design principles that are used to pre-
vent a potentially explosive atmosphere and an ignition source from existing simultan-
eously.
Explosion protection is achieved by means of a gas-proof/dust-proof device encapsu-
lation. This means that potential ignition is prevented, because the potentially explos-
ive atmosphere does not reach the ignition source.
There is a range of different ignition protection types with various safety levels (device
categories) that the device can comply with. All ignition protection types for the assem-
blies used are standardised, and the protection types within the individual categories
should be considered as being equivalent in terms of safety.
3.6.1 Pressure-proof encapsulation "Ex d"
This ignition protection type is used for
device group and category II 2 G (zone 1)
.
Housings for devices of this ignition protection type are so robust that they can with-
stand internal explosions without damage. Design-based measures prevent the explo-
sion from spreading to a potentially explosive atmosphere outside the device (tertiary
explosion protection)
Unavoidable gaps from the inside to the exterior space (e.g. between the housing
body and sealing cover) may exist. They are so small that the flame front of an internal
explosion is extinguished if it escapes.
The gap surfaces must not be cleaned with mechanical devices such as a wire brush
or abrasives. Even small scratches on the gap surfaces represent hazardous damage
that can lead to ignition.

DURAG D-LX 201 Specifications

General

Brand	DURAG
Model	D-LX 201
Category	Measuring Instruments
Language	English