Leybold Oerlikon, Trivac NT16, NT25, Rotary Vane Vacuum Pump ...

Operation
4 Operation
Warning
4.1 ATEX Directive and Flammable Gases Dilution
The TRIVAC NT 16 and 25 Atex Category 3 pumps are designed according
to the requirements of Directive 94/9/EEC Group II, Category 3.
These pumps are suited for operation under ATEX category 3 conditions
corresponding to their respective part number and the special restrictions
which apply for PFPE (for temperature class T3 only).
DOT pumps are not suited for operation in explosion hazard areas or for
pumping explosive substances.
Never use a pump certified for Category 3 internal in an external potentially
explosive atmosphere, as the pump is not designed with respect to
potential ignition sources outside.
In the case of a potential external explosive atmosphere, use only pumps
certified for the ignition category 3 inside and outside.
During normal operation there is no potential source of ignition inside and
outside the pump but, according to the 94/9/EC directive, a rare malfunction
may occur with potential sources of ignition.
In normal operation, even if the pump is designed for flammable gases,
the operation procedure must ensure that the gases are not within their
explosion limits.
When flammable gases are pumped, the following safety measures must
be enforced:
■
Prevent any atmospheric air from entering into the pump.
■ Use an inert gas to dilute the flammable gas being pumped; the concentration
of flammable gas must not exceed 25% to 30% of the lower
explosion limit.
32 130002780_002_A0 - 12/2008 - © Oerlikon Leybold Vacuum