Edwards EXT Series User manual

B777-50-880
Issue D Original
Instruction Manual
EXT Compound Turbomolecular Pumps:
EXT556H and EXT556HF
Description Item Number
EXT556H / DN160ISO-K B777-51-000
EXT556H / DN160CF B777-52-000
EXT556H / DN160ISO-K (fine inlet) B777-61-000
EXT556HF / DN160ISO-K B777-57-000
EXT556HF / DN160CF B777-58-000

Document Template: 02B01010 Attachment 4 Iss. 1
Declaration of Conformity
We, Edwards Limited,
Crawley Business Quarter,
Manor Royal,
Crawley,
West Sussex, RH10 9LW, UK
declare under our sole responsibility, as manufacturer and person within the EU authorised to assemble the
technical file, that the product(s)
EXT556H Compound Turbomolecular Pumps:
EXT556H DN160ISO-K B777-51-000 EXT556HF DN160ISO-K B777-57-000
EXT556H DN160CF B777-52-000 EXT556HF DN160CF B777-58-000
EXT556H DN160ISO-K(fine inlet) B777-61-000
to which this declaration relates is in conformity with the following standard(s) or other normative
document(s)
EN1012-2:1996, A1: 2009 Compressors and Vacuum Pumps. Safety Requirements. Vacuum Pumps
EN61010-1: 2010 Safety Requirements for Electrical Equipment for Measurement, Control and
Laboratory Use. General Requirements
EN61326-1: 2006 Electrical equipment for measurement, control and laboratory Use. EMC
requirements. General requirements
C22.2 61010-1-04: 2004†Safety requirements for electrical equipment for measurement, Control and
laboratory use – Part 1: General requirements
UL61010-1, 2nd Edition†Safety requirements for electrical equipment for measurement, Control and
laboratory use – Part 1: General requirements
EN50581: 2012 Technical Documentation for the Assessment of Electrical and Electronic
Products with respect to the Restriction of Hazardous Substances
†Pumps only comply with the Canadian Standards Authority and Underwriters Laboratory when used with EXDC
80V family of controllers, EXC100E and EXC100L controllers.
and fulfils all the relevant provisions of
2006/42/EC Machinery Directive
2006/95/EC Low Voltage Directive
2004/108/EC Electromagnetic Compatibility (EMC) Directive
2011/65/EU** Restriction of Certain Hazardous Substances (RoHS) Directive
** i.e. The product(s) contain less than - 0.1wt% for hexavalent chromium, lead, mercury, PBB and PBDE; 0.01wt% for
cadmium - in homogeneous materials (subject to the exemptions allowed by the Directive). The RoHS Directive does
not legally apply to industrial vacuum equipment until July 2019 (July 2017 for instruments).
Note: This declaration covers all product serial numbers from the date this Declaration was signed
onwards.
13.01.2014, Burgess Hill
Peter Mea
r
es
GV Technical Support Manager Date and Place
P200-01-420 Issue G
This product has been manufactured under a quality system certified to ISO9001:2008

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Contents
B777-50-880 Issue D
Contents
Section Page
1 Introduction .......................................................................................1
1.1 Scope and definitions ................................................................................................... 1
2 Technical Data ....................................................................................3
2.1 General .................................................................................................................... 3
2.2 Pumping media ........................................................................................................... 3
2.2.1 Pumps without gas purge ............................................................................................... 4
2.2.2 Pumps with gas purge ................................................................................................... 4
2.3 Vent gas specification and vent control data ....................................................................... 5
2.4 Purge gas specification ................................................................................................. 5
2.5 Water cooling ............................................................................................................. 5
2.6 Materials exposed to gases pumped .................................................................................. 6
3 Installation ....................................................................................... 11
3.1 Unpack and inspect .....................................................................................................11
3.2 Typical installation .....................................................................................................11
3.3 Connection to the vacuum system ...................................................................................11
3.3.1 The inlet screen (supplied fitted) ....................................................................................13
3.3.2 Inlet connection .........................................................................................................13
3.3.3 Backing connection .....................................................................................................15
3.4 Vent options, vent valve connection and control ..................................................................15
3.5 Purge gas connection ...................................................................................................17
3.5.1 Connect the purge gas .................................................................................................17
3.5.2 Recommended purge gas flow ........................................................................................17
3.6 Electrical installation ..................................................................................................17
3.7 Cooling ...................................................................................................................19
3.7.1 Introduction .............................................................................................................19
3.7.2 Forced air cooling .......................................................................................................19
3.7.3 Water cooling ............................................................................................................19
3.8 Magnetic Fields ..........................................................................................................20
4 Operation ........................................................................................ 21
4.1 Start up ...................................................................................................................21
4.2 Stand-by ..................................................................................................................21
4.3 Shut-down ................................................................................................................21
4.4 Safety interlocks and control system ................................................................................22
4.5 Bakeout (conflat only) .................................................................................................22
5 Maintenance ..................................................................................... 23
5.1 Introduction .............................................................................................................23
5.2 Bearing maintenance ...................................................................................................23
5.3 Rotor life .................................................................................................................23
5.4 Clean the pump .........................................................................................................23
5.5 Fault finding .............................................................................................................24
6 Storage and disposal ........................................................................... 27
6.1 Storage ...................................................................................................................27
6.2 Disposal ...................................................................................................................27
dcs/8108/08/08

B777-50-880 Issue D
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Contents
7 Service, spares and accessories .............................................................. 29
7.1 Introduction .............................................................................................................29
7.2 Service ....................................................................................................................29
7.3 Spares .....................................................................................................................29
7.3.1 ISX inlet-screen .........................................................................................................29
7.3.2 Inlet-flange seals ........................................................................................................29
7.4 Accessories ...............................................................................................................30
7.4.1 Installation ...............................................................................................................30
7.4.2 EXC controller ...........................................................................................................30
7.4.3 Pump-to-controller cable ..............................................................................................30
7.4.4 EXDC drive modules ....................................................................................................30
7.4.5 BX bakeout band (conflat only) .......................................................................................32
7.4.6 FL20K foreline trap .....................................................................................................32
7.4.7 TAV vent-valve and vent-port adaptor ..............................................................................32
7.4.8 ACX air-cooler ...........................................................................................................32
7.4.9 WCX water-cooler ......................................................................................................33
7.4.10 Vibration isolators ......................................................................................................33
7.4.11 PRX purge-restrictor ....................................................................................................33
7.4.12 VRX vent-restrictor .....................................................................................................33
For return of equipment, complete the HS Forms at the end of this manual.
Illustrations
Figure Page
1 Mounting attitude of the EXT556H pump ............................................................................ 9
2 Typical pumping system ...............................................................................................12
3 Diagram of inlet screen – remove screws 'A' in order to remove the inlet screen.
Do not remove screws 'B' ..............................................................................................14
4 Maximum rate of pressure rise when venting ......................................................................16
5 Dimensions and features of EXT556H pumps .......................................................................18
6 Installation of EXT556H optional accessories and spares .........................................................31

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Contents
B777-50-880 Issue D
Tables
Table Page
1 General information ..................................................................................................... 3
2 Vent gas and vent control data ........................................................................................ 5
3 Purge gas specification ................................................................................................. 5
4 Cooling water specification ............................................................................................ 5
5 Technical data ........................................................................................................... 6
6 List of items supplied ..................................................................................................11
7 Vent restrictor orifice diameter (with atmospheric pressure at the inlet) ....................................15
8 Fault finding .............................................................................................................24
9 ISX inlet-screen .........................................................................................................29
10 Inlet-flange seals ........................................................................................................29
11 EXC controller ...........................................................................................................30
12 Pump-to-controller cable ..............................................................................................30
13 EXDC drive modules ....................................................................................................30
14 BX bakeout band ........................................................................................................32
15 FL20K foreline trap .....................................................................................................32
16 TAV vent-valve and vent-port adaptor ..............................................................................32
17 ACX air-cooler ...........................................................................................................32
18 WCX water-cooler ......................................................................................................33
19 Vibration isolators ......................................................................................................33
20 PRX purge-restrictor ....................................................................................................33
21 VRX vent-restrictor .....................................................................................................33
Associated publications
Publication title Publication number
EXC120/120E/300/300M Turbomolecular Pump Controllers D396-14-880
EXC250E/250L Turbomolecular Pump Controllers D396-36-880
EXDC Turbomolecular Pump Drive Modules D396-40-880

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B777-50-880 Issue D
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Edwards and the Edwards logo are trademarks of Edwards Limited.

© Edwards Limited 2013. All rights reserved. Page 1
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Introduction
B777-50-880 Issue D
1Introduction
1.1 Scope and definitions
This manual provides installation, operation and maintenance instructions for the Edwards EXT556H compound turbo-
molecular pumps. The pump must be used as specified in this manual. The EXT556H pump is designed for use with
an Edwards EXC or EXDC controller. Read this manual and the manual supplied with the controller before installing
and operating the equipment. The controller manual contains details of electrical installation.
Important safety information is highlighted as WARNING and CAUTION instructions; these instructions must be
obeyed. 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 or 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 system of units of measurement. Also, throughout this
manual, wherever flow rates are specified, the abbreviation 'sccm' is used to mean standard cm3min-1: this is a flow
of 1 cm3min-1 at an ambient temperature of 0 °C and a pressure of 1013 mbar (1.013 x 105Pa).
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.
Warning – large attractive forces will be experienced when the pump is subjected to magnetic fields.
Protective conductor terminal.

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Technical Data
B777-50-880 Issue D
2TechnicalData
2.1 General
2.2 Pumping media
CAUTION
Do not use an EXT556H pump to pump gases containing more than 20% oxygen unless a bearing purge is applied
as stated in Section 2. If so, the lubricant will be damaged and the pump will fail prematurely.
Note: Concentrations of gases may be modified by the compression of the pump.
Table 1 - General information
General items Reference data
Performance See Table 5
Dimensions and features See Figure 5
Maximum permitted external magnetic field
EXT556H DN160CF 3 mT horizontal, 5 mT vertical
EXT556H DN160ISO-K 2.5 mT horizontal, 5 mT vertical
EXT556HF ISO and CF variants 50 mT in any orientation
Installation category EN61010 part 1, category 1
Pollution degree CAN/CSA, UL, EN61010 part 1, category 2
Equipment type Fixed equipment, for indoor use only
Operating altitude up to 2000 m
Ambient operating temperature range 5 °C – 35 °C (air cooled)
5 °C – 40 °C (water cooled)
Relative humidity 10 – 90% non condensing
Electrical supply 80 V
Ambient storage temperature range -30 °C - 70 °C
WARNING
Vent dangerous gases and gas mixtures safely. Do not expose people to these gases.
WARNING
Do not use EXT556H pumps to pump explosive gas mixtures as the pumps are not suitable for
this purpose.
WARNING
Do not use the EXT556H pump to pump mercury vapour, or allow mercury to come into contact
with the pump. If so, the rotor may corrode and fail.

B777-50-880 Issue D
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Technical Data
2.2.1 Pumps without gas purge
The pumps are designed to pump the following residual gases normally used in high vacuum systems:
air
nitrogen
krypton
neon
hydrogen
propane
methane
carbon dioxide
carbon monoxide
helium
argon
ethane
butane
Use the pumps to pump oxygen and water vapour subject to the following conditions:
Oxygen
The oxygen concentration must be less than 20% by volume unless a bearing purge is applied as detailed in
Section 2.2.2.
Water vapour
Ensure that vapour does not condense inside the pump – refer to Section 3.7.3.
If pumping a gas not previously listed, contact the supplier for advice. If not, contact the supplier as the warranty
on the pump may be invalidated.
The pumps are not suitable for pumping aggressive or corrosive gases.
2.2.2 Pumps with gas purge
When purged with an inert gas the pumps can be used to pump oxygen in concentrations above 20% by volume.

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Technical Data
B777-50-880 Issue D
2.3 Vent gas specification and vent control data
Although the pump may be vented to atmosphere, relatively high air humidity may greatly increase the subsequent
pump-down time. To reduce pump-down times, vent the pump with dry, clean gases.
2.4 Purge gas specification
2.5 Water cooling
The following water cooling specification corresponds to a typical high quality drinking water specification. Check
with the water supply authority if in doubt about the quality of the supply.
Table 2 - Vent gas and vent control data
Vent gas system items Reference data
Vent gas Dry air, nitrogen, argon or other inert gases
Maximum dew point at atmospheric pressure -22 °C
Maximum size of particulate 1 micron
Maximum concentration of oil 0.1 parts per million
Time for rotational speed to reach 50% >15 seconds
Maximum allowed rate of pressure rise see Figure 4
Table 3 - Purge gas specification
Purge gas system items Reference data
Purge gas Dry nitrogen, argon or other inert gases
Maximum dew point at atmospheric pressure -22 °C
Maximum size of particulates 1 micron
Maximum concentration of oil 0.1 parts per million
Allowable purge gas flow (when required) 20 to 150 sccm (0.33 to 2.48 mbar l s-1,
33 to 248 Pa l s-1)
Recommended purge gas flow 25 sccm (0.42 mbar l s-1, 42 Pa l s-1)
Maximum allowable purge gas supply pressure 2 bar gauge (29 psig, 3 x 105Pa)
Table 4 - Cooling water specification
Cooling water system items Reference data
Quality Mechanically clean and optically with no deposits
or turbidity
pH value 6.0 to 8.0
Maximum calcium carbonate concentration 75 parts per million
Maximum chloride concentration 100 parts per million
Minimum oxygen concentration 4 parts per million
Recommended water cooling flow rate (at 15 °C) 15 l hr-1
Water temperature See Table 5
Maximum water pressure 5 bar (gauge), 73.5 psig, 6 x 105Pa
Materials exposed to cooling water Copper, brass and nickel plating

B777-50-880 Issue D
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Technical Data
2.6 Materials exposed to gases pumped
The following materials and component types are exposed to the gases pumped: aluminium alloys, stainless steels,
fluoroelastomer and nitrile O-rings, hydrocarbon lubricant, rare earth magnets, silicon nitride, phenolic resin and
carbon fibre epoxy resin.
Table 5 - Technical data
Parameter EXT556H Notes
Mass EXT556H DN160ISO-K 13.4 kg
Mass EXT556H DN160CF 21.2 kg
Mass EXT556HF DN160ISO-K 19.3 kg
Mass EXT556HF DN160CF 20.5 kg
Main inlet flange DN160ISO-K/DN160CF
Outlet flange DN25NW
Vent port 1/8 inch BSP
Purge port 1/8 inch BSP
Inlet pumping speed *
N2540 l s-1
He 580 l s-1
H2500 l s-1
Ar 510 l s-1
Inlet compression ratio †
N2>1010 Pb < 20 mbar
He 108Pb < 12 mbar
H2106Pb < 7 mbar
Ar >1010 Pb < 20 mbar
Ultimate pressure ‡
CF <10-10 mbar
ISO <2 x 10-9 mbar
Minimum backing pump
displacement 12 m3 h-1
Recommended backing pump RV12
Maximum continuous inlet pressure
(light gas pumping) ** These pressures relate to the aluminium envelope variant
B777-51-000. Performance will vary
for other pump variants when
air cooled.
Forced air cooled, 30 °C ambient 1.5 x 10-3 mbar
Forced air cooled, 35 °C ambient 1.0 x 10-3 mbar
Water cooling at 15 °C 2.0 x 10-3 mbar

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Technical Data
B777-50-880 Issue D
Maximum continuous inlet pressure
(argon pumping) ** These pressures relate to the aluminium envelope variant
B777-51-000. Performance will vary
for other pump variants when
air cooled.
Forced air cooled, 30 °C ambient 8.0 x 10-4 mbar
Forced air cooled, 35 °C ambient 5.0 x 10-4 mbar
Water cooling at 15 °C 1.0 x 10-3 mbar Water cooling while pumping high
concentrations of argon is not
recommended
Maximum continuous backing
pressure (light gas pumping) ** These pressures relate to the
aluminium envelope variant
B777-51-000. Performance will vary
for other pump variants when air
cooled.
Forced air cooled, 30 °C ambient 10 mbar
Forced air cooled, 35 °C ambient 6 mbar
Water cooling at 15 °C 7.5 mbar
Maximum continuous backing
pressure (argon pumping) ** These pressures relate to the
aluminium envelope variant
B777-51-000. Performance will vary
for other pump variants when air
cooled.
Forced air cooled, 30 °C ambient 2.9 mbar
Forced air cooled, 35 °C ambient 1.8 mbar
Water cooling at 15 °C 2.2 mbar Water cooling while pumping high
concentrations of argon is not
recommended
Operating attitude See note at right Vertical (inlet uppermost) to
Horizontal, not inverted. Range of
rotation of ± 60° about the axis.
Refer to Figure 1.
Nominal rotational speed 50000 rpm
Start time to 90% speed:
EXC250 < 8 minutes
EXC300 < 8 minutes
EXDC160 < 8 minutes
Table 5 - Technical data (continued)
Parameter EXT556H Notes

B777-50-880 Issue D
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Technical Data
Cooling method †† forced air / water
Ambient air temperature for forced
air cooling 0 °C – 35 °C
Minimum cooling water flow rate
(water at 15 °C) 15 l h-1
Water temperature 10 °C – 20 °C
Noise level at 1 metre <60 dBA
Recommended controllers EXC250, EXC300, EXDC160
Quiescent power consumption 35 W
*Pumping speeds are without inlet screen.
The coarse and fine inlet screen reduces the pumping speed by 11% and 17% respectively.
†Pb = backing pressure.
‡Ultimate pressure is measured 48 hours after bakeout with a 2 stage rotary pump.
** Above this pressure the rotational speed of the pump drops below nominal. Heavy gas for example an
atomic mass greater than 28 AMU and light gas for example atomic mass less than or equal to 28 AMU.
†† If air cooling is required, Edwards recommends the ACX555.
Table 5 - Technical data (continued)
Parameter EXT556H Notes

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Technical Data
B777-50-880 Issue D
Figure 1 - Mounting attitude of the EXT556H pump
1. Inlet
2. Backing port

B777-50-880 Issue D
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Installation
B777-50-880 Issue D
3 Installation
3.1 Unpack and inspect
CAUTION
Do not damage the envelope surface of the HF variant as this may cause corrosion and a reduction in
performance. In this event the pump must be returned to the nearest service centre.
Take care when unpacking the pump to avoid excessive mechanical shocks which could damage the bearings and
reduce the life of the pump. The pump is supplied with the inlet and outlet sealed to prevent entry of dust and
vapour. Do not remove these seals until ready to install the pump on the vacuum system.
Remove the outer cardboard packaging and check the pump. If the pump is damaged, notify the supplier and carrier
in writing within three days; state the item number of the pump together with the order number and supplier's
invoice number. Retain all the packing materials for inspection. Do not use the pump if it is damaged.
Check that the package contains the items listed in Table 6. If any of these items is missing, notify the supplier in
writing within three days. If the pump is not to be used immediately, store the pump in suitable conditions as
described in Section 6.1. Retain all packing materials for use if the pump is returned for service.
3.2 Typical installation
A typical pump system with an EXT556H pump is shown in Figure 2.The accessories available for the EXT556H pump
are detailed in Section 7.4. The accessories are shown in Figure 6.
3.3 Connection to the vacuum system
Carefully remove the pump from packaging media and connect to the vacuum system.
WARNING
The EXT556H DN160CF pump variant weighs 21 kg. Observe correct manual handling techniques
when manoeuvring it.
WARNING
Install the pump on the vacuum system before connecting the controller to the power supply. This
will ensure that the pump cannot operate and injure people during installation.
Table 6 - List of items supplied
Qty Description
1 EXT556H turbomolecular pump
1Inletscreen(fitted)
1 Inlet seal (trapped 'O' ring, co-seal or copper compression gasket)

B777-50-880 Issue D
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Installation
Figure 2 - Typical pumping system
1. Alternative position for
vent-valve
2. Vacuum system
3. High-vacuum gauge
4. Inlet-screen (supplied fitted)
5. EXT pump
6. Backing valve
7. Vacuum gauge
8. Flexible bellows
9. Foreline trap
10.Rotary backing pump
11.Mist filter
12.Cooling water connectors
13.EXC controller
14.Air cooler
15.PRX10 purge restrictor
16.Regulated purge gas supply
17.Vent-valve

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Installation
B777-50-880 Issue D
3.3.1 The inlet screen (supplied fitted)
CAUTION
Removal of the inlet screen could allow debris to fall into the pump, which could cause serious damage to the
pump.
CAUTION
Do not remove the three screws which retain the locking plate ('B' in Figure 3). If so, the pump settings may
change and the pump may cease to operate or have a shortened life.
Do not remove the inlet screen if there is a possibility of debris falling into the pump. If the inlet screen are removed,
the pumping speed through the inlet will increase by 11% for a coarse and 17% for a fine screen.
To remove the inlet screen, undo the three screws ('A') which hold it down (Figure 3). If the inlet screen needs
replacing, do so by undoing these screws, changing the inlet screen, and replacing the screws. Ensure that screws
are firmly tightened.
3.3.2 Inlet connection
CAUTION
The pump is able to operate up to the horizontal attitude axially. If it is mounted off-vertical, ensure that the
backing port is within 60° of vertical. Refer to Figure 1.
Ensure that the EXT556H pump is securely fixed to the vacuum system following the instructions below.
Make sure that the pump inlet and all components fitted to the pump inlet are clean and dust free. If the pump inlet
is not kept clean the pump down time may be increased. Use the vacuum seal provided with the pump.
When using an EXT556H ISO160 pump, connect it to the vacuum system using an ISO160 rotatable flange with a full
complement of bolts. Alternatively use at least 8 claw clamps.
When using an EXT556H DN160CF, use a full complement of 20 M8 bolts to attach the pump to the vacuum system.
If the inlet flange of the EXT556H is not connected to a rigid, firmly fixed vacuum system, ensure that the base of
the pump is fixed to a firm support. Remove the four feet and secure the pump using eight M8 bolts through the
tapped fixing holes in the base of the pump. These bolts should be in ISO 898-1 class 8.8 or higher, and should be
tightened up to approximately 7Nm torque. When using a WCX555 water cooling accessory, mount through the
cooling plate into the tapped holes on the base of the pump.
If the pump inlet is connected to thevacuum system using a vibration isolator, use the tapped fixing holes in the base
of the pump to secure the pump to a firm support as described above. Alternatively, fit suitable restraints to prevent
movement of the pump and fracture of the vibration isolator in the unlikely event of a seizure of the pump rotor.
WARNING
Removal of inlet screen will expose people to the risk of injury from sharp edges.
WARNING
Ensure that the EXT556H pump is securely fixed to the vacuum system following the instructions
below. If not, and the pump seizes, the stored energy of the rotor can cause rapid movement of
the pump, which may cause injury to people and further damage to equipment.

B777-50-880 Issue D
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Installation
Figure 3 - Diagram of inlet screen – remove screws 'A' in order to remove the inlet screen.
Do not remove screws 'B'