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www.crouse-hinds.de EATON 2.5.37
Ex-safety switches
Safety first
Occupational safety always has
top priority in any industrial fa-
cility. Whenever maintenance,
cleaning, or repair work is
necessary, it must be possible
to safely and reliably isolate
machines and installations from
the electrical power supply.
Safety switches are the most
widely used and cost effective
isolation method available.
However, not all isolator switch-
es are created equal. If safety
switches that meet the require-
ments of the Raw Materials and
Chemical Industry Employers’
Liability Insurance Association
(BG RCI) are used, time-con-
suming measures (e.g. the
complete disconnection of mo-
tors) can be eliminated. Eaton’s
Crouse-Hinds series GHG981
safety switches meet these
standards.
In addition, the GHG981 safety
switches have been approved
for use in zone 22 areas con-
taining explosive dust. With the
built-in padlocking facilities, they
can be used as a load break
switch with full confidence they
will provide the required safety
and personnel protection.
Ready for harsh environments
The enclosures for our
GHG981 safety switches are
designed with IP66 environ-
mental protection and are avail-
able in powder-coated sheet
steel, glass-reinforced polyester
(GRP), or electro-polished stain-
less steel. They are impact re-
sistant and robust, corrosion-re-
sistant, and are suitable for use
in harsh industrial environments
with extreme ambient tempera-
tures from -55 °C to +55 °C.
Lock-out/tag-out capability
All GHG981 safety switches
come with built-in lock-out/
tag-out capability and can be
locked in the “OFF” position
by means of max. 3 padlocks.
While switched to the “OFF”
position, the enclosure covers
of safety switches cannot be
opened without destroying the
enclosure. This provides an ex-
tra level of safety as it prevents
access to a switch locked in
the “OFF” position, eliminating
any risk of tampering with the
switch position or electrical con-
nections.
Electrical equipment for use
in areas with combustible
dust
Combustible dust can be ig-
nited by electrical apparatus in
various ways:
by apparatus surface temper-
atures that are higher than the
ignition or glow temperature of
the respective dust. The tem-
perature at which the dust ig-
nites is dependent on the prop-
erties of the dust, on whether it
is present in the form of a cloud
or deposits, on the thickness
of the layer and on the type of
heat source
by sparks at electrical parts
such as switches, contacts,
commutators, brushes or sim-
ilar
by the discharge of stored elec-
trostatic energy
by radiated energy (e.g. electro-
magnetic radiation)
by magnetic impact or friction
sparks or a rise in temperature
originating from the apparatus.
To avoid ignition hazards, it is
necessary that:
• the temperature of any sur-
faces on which dust deposits
can form or that can come
into contact with a cloud of
dust are kept at a temper-
ature that is lower than the
limiting temperatures laid
down in EN 50028-1-2
• all parts with electric sparks
or with temperatures above
the ignition or glow tempera-
ture of the dust are built into
an enclosure that prevents
the ingress of dust in a suita-
ble manner, or
• the energy of the electric
circuits is limited to such a
degree, that sparks or tem-
perature that could ignite
combustible dust are avoided
• all other ignition sources are
avoided.