2. Introduction
2.1 Scope of this manual
This manual provides installation, operation and maintenance instructions for the nXDS
series of scroll pump. The pump must be used as specified in this manual or the
protection provided by the equipment may be impaired. Read this manual before
installing and operating the pump.
2.2 ATEX directive implication
This equipment is designed to meet the requirements of Group II Category 3G in
respects to ignition sources internal to the pump. This classification is in accordance with
Directive 2014/34/EU.
The pumping mechanism and its mechanical components exposed to the "INTERNAL
ATMOSPHERES" within the nXDS pump system is defined as: equipment group II,
equipment category 3 - in accordance with the ATEX directive. This designation ONLY
applies to the mechanical pumping mechanism, which is hermetically sealed from the
external pump system and its operating environment. An ATEX category has not been
assigned in respect of potential ignition sources on the outside of the equipment as the
equipment has not been designed for use where there is an external potentially
explosive atmosphere.
There is no potential source of ignition within the pump during normal operation but
there may be potential sources of ignition under conditions of rare or unexpected
malfunction as defined in the directive. As a result of this, it is necessary to consider the
potential consequences of ignition sources occurring under rare or expected
malfunction. (Ref ATEX137 1992/92/EC).
When flammable materials are present within the equipment you must:
▪
Not allow air to enter the equipment.
▪
Ensure the system is leak tight.
▪
Use an inert gas purge (for example, nitrogen) to dilute any flammable gasses or
vapours entering the pump inlet, and use an inert gas purge to reduce the
concentration of flammable gases or vapours in the pump and in the exhaust
pipeline, to less than one quarter of the gases published Lower Explosion Limits
(LEL).
Do not pump pyrophoric materials, process debris could produce an ignition source on
the scroll surface.
Do not locate the pump in an ATEX zoned area, the ATEX specification is not applicable
for external atmospheres.
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A73501880_G - Introduction
Summary of Contents for nXDS10i nXDS15i
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