| Ex-Info : Types of Protection |
| |
| Ingress Protection (IP) |
Protection Against
Solid Objects |
Protection against
Liquids |
| No. |
Description |
| 0 |
No protection |
| 1 |
Objects greater than 50 mm |
| 2 |
Objects greater than 12 mm |
| 3 |
Objects greater than 2.5 mm |
| 4 |
Objects greater than 1 mm |
| 5 |
Dust protected |
| 6 |
Dust tight |
|
| No. |
Description |
| 0 |
No protection |
| 1 |
Vertically dripping water |
| 2 |
Dripping water tilted up to 15 degrees |
| 3 |
Spraying water at angle up to 60 degrees |
| 4 |
Splashing water from any direction |
| 5 |
Low pressure water jets |
| 6 |
Strong jets of water |
| 7 |
The effects of immersion to depth of 1 m |
| 8 |
Submersion |
|
|
| Oil Immersion Ex o |
| Principle: |
The electrical apparatus or parts
of the electrical apparatus are
immersed in oil in such a way that
an explosive atmosphere which
may be above the oil or outside
the enclosure cannot be ignited. |
| Applications: |
| Transformers
(hardly used any more) |
| |
| Pressurised Apparatus Ex p |
| Principle: |
The entry of a surrounding atmosphere
into the enclosure of the electrical
apparatus is prevented by maintaining,
inside the enclosure, a protective gas at a
higher pressure than that of the surrounding
atmosphere. The overpressure is maintained
either with or without a continuous flow of
the protective gas. |
| Applications: |
| Terminal and junction boxes,
control stations for the installation
of large equipment, whole rooms
for electrical installations,
diagnostic equipment,
PCs |
| |
| Powder Filling Ex q |
| Principle : |
The enclosure of an electrical apparatus
is filled with a material in a finely
granulated state so that, in the intended
conditions of service, any arc occurring
within the enclosure will not ignite the
surrounding atmosphere. No ignition
shall be caused either by flame or by
excessive temperature of the surface of
the enclosure. |
| Applications : |
| Tranformers, capacitors,
electronic Parts,
(not often used) |
| |
| Flameproof Enclosure Ex d |
| Principle : |
Parts which can ignite an explosive
atmosphere are enclosed in an
enclosure, that withstands the
explosion pressure in its inside
and prevents the transfer of the
explosion to the enviroment. |
| Applications: |
| Switchgear, control equipment,
display devices, control panels,
motors, transformers, lighting fittings
and other sparking parts |
| |
| Increased Safety Ex e |
| Principle: |
Increased safety is a type of
protection by which measures are
applied to prevent with a major
degree of safety the possibility of
excessive temperatures and of the
occurrence of arcs and sparks in
the interior and on the external
parts of electrical apparatus which
does not produce them in normal
operation. |
| Applications: |
Terminal boxes,
control stations for the installation of
equipment which is protected by
another type of protection,
squirrel-cage motors, lighting fittings
|
| |
| Encapsulation Ex m |
| Principle: |
Parts that could ignite an explosive
atmosphere are enclosed in a resin
sufficiently resistant to environmental
influences in such a way that this
explosive atmosphere cannot be
ignited either by sparking or heating
which may occur within the
encapsulation. |
| Applications: |
| switchgear for low power,
control equipment,
display devices,
sensors |
| |
| Intrinsic Safety Ex i |
| Principle: |
| The electrical equipment which is
installed in the hazardous area has to
have only intrinsically safe circuits.
A circuit is intrinsically safe, when no
spark or heat is able to ignite an
explosive atmosphere under fixed
conditions. These predefined conditions
include the normal operation and
certain failure modes. |
| Applications: |
| Instrumentation,
Information technology |
