© Edwards Limited 2008. All rights reserved.
Page 1
Edwards and the Edwards logo are trademarks of Edwards Limited.
Introduction
B722-20-880 Issue D
1
Introduction
1.1
Scope and definitions
This manual provides installation, operation and maintenance instructions for the Edwards EXT70H 24 V,
EXT70Hi 24 V, EXT255H 24 V and EXT255Hi 24 V Compound Molecular Pumps. These pumps must be used as specified
in this manual. It is not possible to purchase an EXT70Hi 24 V pump; an EXT70Hi 24 V pump is an EXT70H/ISO63 24 V
pump fitted with an interstage-port accessory: see
The EXT Compound Molecular Pumps are designed for use with a Edwards Turbomolecular Pump Drive Module
(abbreviated to EXDC Drive Module in the remainder of this manual). Read this manual and the instruction manual
supplied with your EXDC Drive Module before you attempt to install or operate the equipment. The instruction manual
supplied with your EXDC Drive Module contains details of how to set up the Module and the logic interface.
Important safety information in this manual is highlighted as WARNING and CAUTION instructions; you must obey
these instructions. The use of WARNINGS and CAUTIONS is defined below.
CAUTION
Cautions are given where failure to observe the instruction could result in damage to the equipment, associated
equipment and process.
In accordance with the recommendations of EN61010, the following warning symbols may appear on the pump or its
accessories:
The units used throughout this manual conform to the SI international system of units of measurement. Also
throughout this manual, wherever flow rates are specified, the abbreviation ‘sccm’ is used to mean
‘standard cm
3
min
-1
: this is a flow of 1 cm
3
min
-1
at an ambient temperature of 0 °C and a pressure of 1013 mbar
(1.013 x 10
5
Pa).
WARNING
Warnings are given where failure to observe the instruction could result in injury or death to
people.
Warning - refer to accompanying documentation.
Warning - risk of electric shock.
Warning - hot surfaces.
Protective conducter terminal.
