ATEX
19
GA03107_002_A4 - 09/2015 - © Oerlikon Leybold Vacuum
Example for calculating p
E
and p
a
for a T2 application
A RUVAC WA 501 is being operated together with a backing pump at a pump-
ing speed of approximately 150 m
3
/ h. Compliance with temperature classifica-
tion T2 is required. This will be the case for the WA 501 in all operating modes
(see normal operation).
The nominal pumping speed of the WA 501 is 505 m
3
/ h.
k
th
= Nominal pumping speed RUVAC /Nominal pumping speed vacuum pump
= 505 m
3
/ h / 150 m
3
/ h = 3.36
According to equation (2):
p
S
= p
E
≤ ∆p
max
/ (k
th
– 1)
∆p
max
(WA 501) = 80 mbar (see Table)
Thus it follows that:
p
S
≤ p
E
= 80 mbar / (3.36 – 1) = 34 mbar approx.
Result:
Under these conditions the WA 501 may be switched on at an inlet pressure (=
process pressure) of
34 mbar
max. and continuously operated. Here the
requirements of temperature classification T2 are fulfilled at all times.
Related Electrical Equipment
Provided the pump is approved for operation in explosion hazard areas, all
electrical equipment supplied together with the pump like, for example,
valves, sensors, is also approved for operation in such areas. The same con-
ditions which apply to operation of the pump apply also to the accessories.
Related Accessories
The Oerlikon Leybold Vacuum accessories available for this pump are also
suited for operation in explosion hazard areas. The same conditions which
apply to operation of the pump apply also to the accessories. When using
other accessories with this pump, it needs to be ensured that such accesso-
ries are suited for operation in explosion hazard areas.
Areas of Application
The inside (the process gas side) of this vacuum pump is so designed and
rated that the occurrence of foreseeable ignition sources can be excluded
during normal operation. Provided the pump is operated within the limits of
the parameters specified in the Operating Instructions, the pump will offer a
normal degree of protection. It is therefore suited for operation under condi-
tions under which it is unlikely that explosive atmospheres are caused by
gases, vapors or mists in the air or should these occur then only rarely and
for a short period of time (i.e. Zone 2). The same conditions apply to outside
components of the pumps which have been certified.
Summary of Contents for RUVAC WA
Page 67: ...Notes 67 GA03107_002_A4 09 2015 Oerlikon Leybold Vacuum ...
Page 68: ...68 GA03107_002_A4 09 2015 Oerlikon Leybold Vacuum EC Declaration of Conformity ...
Page 69: ...69 GA03107_002_A4 09 2015 Oerlikon Leybold Vacuum EC Incorporation Declaration ...
Page 71: ...Index 71 GA03107_002_A4 09 2015 Oerlikon Leybold Vacuum ...
