Atlas Copco GHS 350 VSD+ User manual

Atlas Copco
Oil-sealed rotary screw vacuum pumps
GHS 350 VSD+, GHS 585 VSD+, GHS 730 VSD+,
GHS 900 VSD+, GHS 350 VSD+ Turbo,
GHS 585 VSD+ Turbo, GHS 730 VSD+ Turbo
Instruction Book
6996 0227 40
Issue C

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Atlas Copco
Oil-sealed rotary screw vacuum pumps
GHS 350 VSD+, GHS 585 VSD+, GHS 730 VSD+,
GHS 900 VSD+, GHS 350 VSD+ Turbo,
GHS 585 VSD+ Turbo, GHS 730 VSD+ Turbo
From following serial No. onwards: API 850 800
Instruction book
Original instructions
Copyright notice
Any unauthorized use or copying of the contents or any part thereof is prohibited. This applies in
particular to trademarks, model denominations, part numbers and drawings.
This instruction book is valid for CE as well as non-CE labelled machines. It meets the
requirements for instructions specified by the applicable European directives as identified in the
Declaration of Conformity.
2017 - 09
No. 6996 0227 40 Issue C
www.atlascopco.com

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6996 0227 40 5
Table of contents
1Safety precautions......................................................................................................................................7
1.1 Safety icons...................................................................................................................................................7
1.2 General precautions......................................................................................................................................7
1.3 Safety precautions during installation ...........................................................................................................8
1.4 Safety precautions during operation .............................................................................................................9
1.5 Safety precautions during maintenance or repair .......................................................................................10
2General description...................................................................................................................................12
2.1 What is vacuum and how is flow rate understood.......................................................................................12
2.2 Introduction..................................................................................................................................................13
2.3 Flow diagram...............................................................................................................................................15
2.4 Condensatesystem.....................................................................................................................................16
2.5 Regulating system.......................................................................................................................................16
2.6 Electrical system .........................................................................................................................................17
3Elektronikon® Graphic controller............................................................................................................18
3.1 Elektronikon® Graphic controller ................................................................................................................18
3.2 Control panel...............................................................................................................................................20
3.3 Icons used...................................................................................................................................................21
3.4 Main screen.................................................................................................................................................24
3.5 Calling up menus.........................................................................................................................................27
3.6 Inputs menu.................................................................................................................................................28
3.7 Outputs menu..............................................................................................................................................31
3.8 Counters......................................................................................................................................................33
3.9 Control mode selection ...............................................................................................................................34
3.10 Service menu ..............................................................................................................................................36
3.11 Modifying the setpoint .................................................................................................................................39
3.12 Event history menu......................................................................................................................................41
3.13 Modifying general settings ..........................................................................................................................43
3.14 Info menu ....................................................................................................................................................46
3.15 Week timer menu........................................................................................................................................47
3.16 User password menu ..................................................................................................................................55
3.17 Web server..................................................................................................................................................56
3.18 Programmable settings ...............................................................................................................................64
4Installation .................................................................................................................................................66
4.1 Dimension drawings....................................................................................................................................66
4.2 Installation proposal ....................................................................................................................................68
4.3 Electrical connections .................................................................................................................................71
4.4 Pictographs .................................................................................................................................................75

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6 6996 0227 40
5Operating instructions..............................................................................................................................77
5.1 Initial start-up...............................................................................................................................................77
5.2 Starting........................................................................................................................................................78
5.3 During operation..........................................................................................................................................79
5.4 Taking out of operation ...............................................................................................................................80
5.5 Stopping......................................................................................................................................................80
6Maintenance...............................................................................................................................................81
6.1 Preventive maintenance schedule..............................................................................................................81
6.2 Oil specifications .........................................................................................................................................85
6.3 Drive motor..................................................................................................................................................86
6.4 Air filter........................................................................................................................................................86
6.5 Oil and oil filter change................................................................................................................................87
6.6 Coolers........................................................................................................................................................90
6.7 Oil separator change...................................................................................................................................90
6.8 Pressure switch...........................................................................................................................................91
6.9 Service kits..................................................................................................................................................92
6.10 Storage after installation .............................................................................................................................92
6.11 Disposal of used material............................................................................................................................92
7Problem solving ........................................................................................................................................93
8Technical data .........................................................................................................................................102
8.1 Reading on display....................................................................................................................................102
8.2 Electrical cable size and fuses..................................................................................................................103
8.3 Reference condition and limitations..........................................................................................................110
8.4 Vacuum pump data...................................................................................................................................110
8.5 Technical data Elektronikon® controller ...................................................................................................116
9Instructions for use.................................................................................................................................117
10 Guidelines for inspection .......................................................................................................................118
11 Declaration of conformity.......................................................................................................................119

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6996 0227 40 7
1 Safety precautions
1.1 Safety icons
Explanation
Danger for life
Warning
Important note
1.2 General precautions
General precautions
1. The operator must employ safe working practices and observe all related work safety requirements
and regulations.
2. If any of the following statements does not comply with the applicable legislation, the stricter of the two
shall apply.
3. Installation, operation, maintenance and repair work must only be performed by authorized, trained,
specialized personnel.
4. The vacuum pump is designed for handling atmospheric air only. No other gases, vapors or fumes
should be exposed to the vacuum pump intake or processed by the vacuum pump.
5. Before any maintenance, repair work, adjustment or any other non-routine checks:
Stop the vacuum pump
Press the emergency stop button
Switch off the voltage
Make sure that the vacuum pump system is at atmospheric pressure level.
Lock Out - Tag Out (LOTO):
Open the power isolating switch and lock it with a personal lock
Tag the power isolating switch with the name of the service technician.
On units powered by a frequency converter, wait 10 minutes before starting any electrical
repair.
Never rely on indicator lamps or electrical door locks before maintenance work, always
disconnect and check with measuring device.
If the machine is equipped with an automatic restart after voltage failure function and if this
function is active, be aware that the machine will restart automatically when the power is
restored if it was running when the power was interrupted!
In a domestic environment, this product may cause radio interference in which case
supplementary mitigation measures are required.

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8 6996 0227 40
6. Avoid contact with pump intake during operation.
7. The owner is responsible for maintaining the unit in safe operating condition. Parts and accessories
shall be replaced if unsuitable for safe operation.
8. It is not allowed to walk or stand on the unit or on its components.
1.3 Safety precautions during installation
All responsibility for any damage or injury resulting from neglecting these precautions, or non
observance of the normal caution and care required for installation, operation, maintenance
and repair, even if not expressly stated, will be disclaimed by the manufacturer.
Precautions during installation
1. The machine must only be lifted using suitable equipment in accordance with the applicable safety
regulations. Loose or pivoting parts must be securely fastened before lifting. It is strictly forbidden to
dwell or stay in the risk zone under a lifted load. Lifting acceleration and deceleration must be kept
within safe limits. Wear a safety helmet when working in the area of overhead or lifting equipment.
2. The unit is designed for indoor use. If the unit is installed outdoors, special precautions must be taken;
consult your supplier.
3. Place the machine where the ambient air is as cool and clean as possible. If necessary, install a
suction duct. Never obstruct the air inlet. Water handling capacity is limited.
4. Any blanking flanges, plugs, caps and desiccant bags must be removed before connecting the pipes.
5. Vacuum connection and discharge pipes must be of correct size and suitable for the working pressure
and temperature. Never use frayed, damaged or worn hoses. Distribution pipes and connections must
be of the correct size and suitable for the working pressure.
6. The aspirated air must be free of flammable fumes, vapours and particles, e.g. paint solvents that can
lead to internal fire or explosion.
7. The external force extended on the in- and outlet connection is limited to 10 kg; the connection pipes
must be free of strain. No supports may be fixed to the canopy of the machine..
8. If remote control is installed, the machine must bear a clear sign stating:
DANGER: This machine is remotely controlled and may start without warning.
The operator has to make sure that the machine is stopped, depressurized and that the electrical
isolating switch is open, locked and labelled with a temporary warning before any maintenance or
repair. As a further safeguard, persons switching remotely controlled machines shall take adequate
precautions to ensure that there is no one checking or working on the machine. To this end, a suitable
notice shall be affixed to the start equipment.
9. Air-cooled machines must be installed in such a way that an adequate flow of cooling air is available
and that the exhausted air does not recirculate to the inlet.
10. The electrical connections must correspond to the applicable codes. The machines must be earthed
and protected against short circuits by fuses in all phases. A lockable power isolating switch must be
installed near the pump.
11. On machines with automatic start/stop system or if the automatic restart function after voltage failure is
activated, a sign stating "This machine may start without warning" must be affixed near the instrument
panel.
12. Never remove or tamper with the safety devices, guards or insulation fitted on the machine.
13. Piping or other parts with a temperature in excess of 70˚C (158˚F) and which may be accidentally
touched by personnel in normal operation must be guarded or insulated. Other high temperature piping
must be clearly marked.
14. If the ground is not level or can be subject to variable inclination, consult the manufacturer.

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6996 0227 40 9
15. Pump outlet air contains traces of oil mist. Ensure compatibility with the working environment.
16. Any vacuum pump placed in an application with inlet gas stream temperatures above the published
maximum temperature should be approved by Atlas Copco prior to start-up.
17. For water-cooled machines, the cooling water system installed outside the machine has to be
protected by a safety device with set pressure according to the maximum cooling water inlet pressure.
Also consult sections Safety precautions during operation and Safety precautions during
maintenance or repair.
These precautions apply to machinery processing or consuming air or inert gas. Processing
of any other gas requires additional safety precautions typical to the application which are not
included herein.
Some precautions are general and cover several machine types and equipment; hence some
statements may not apply to your machine.
1.4 Safety precautions during operation
All responsibility for any damage or injury resulting from neglecting these precautions, or
non-observance of the normal caution and care required for installation, operation,
maintenance and repair, even if not expressly stated, will be disclaimed by the manufacturer.
Precautions during operation
1. Never touch any piping or components of the vacuum pump during operation.
2. Use only the correct type and size of hose end fittings and connections. Make sure that a hose is fully
depressurized before disconnecting it.
3. Persons switching on remotely controlled machines shall take adequate precautions to ensure that
there is no one checking or working on the machine. To this end, a suitable notice shall be affixed to
the remote start equipment.
4. Never operate the machine when there is a possibility of taking in flammable or toxic fumes, vapours or
particles.
5. Never operate the machine below or in excess of its limit ratings.
6. Keep all bodywork doors shut during operation. The doors may be opened for short periods only, e.g.
to carry out routine checks. Wear ear protectors when opening a door.
On vacuum pumps without bodywork, wear ear protection in the vicinity of the machine.
7. People staying in environments or rooms where the sound pressure level reaches or exceeds 80 dB(A)
shall wear ear protectors.
8. Periodically check that:
All guards are in place and securely fastened
All hoses and/or pipes inside the machine are in good condition, secure and not rubbing
There are no leaks
All fasteners are tight
All electrical leads are secure and in good order
Safety valves and other pressure relief devices are not obstructed by dirt or paint
Air outlet valve and air net, i.e. pipes, couplings, manifolds, valves, hoses, etc. are in good repair,
free of wear or abuse
Electrical cabinet air cooling filters are not clogged
9. If warm cooling air from vacuum pumps is used in air heating systems, e.g. to warm up a workroom,
take precautions against air pollution and possible contamination of the breathing air.
10. Do not remove any of, or tamper with, the sound-damping material.
11. Never remove or tamper with the safety devices, guards or insulations fitted on the machine.

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10 6996 0227 40
12. The oil separator tank can be slightly pressurised. Do not open and do not leave oil filler or drain plugs
open during operation.
13. Do not use the pump as a compressor.
14. Never run the pump without the air intake filter mounted.
15. On water-cooled vacuum pumps using open circuit cooling towers, protective measures must be taken
to avoid the growth of harmful bacteria such as Legionella pneumophila bacteria.
Also consult sections Safety precautions during installation and Safety precautions during
maintenance or repair. These precautions apply to machinery processing or consuming air or
inert gas. Processing of any other gas requires additional safety precautions typical to the
application which are not included herein.
Some precautions are general and cover several machine types and equipment; hence some
statements may not apply to your machine.
1.5 Safety precautions during maintenance or repair
All responsibility for any damage or injury resulting from neglecting these precautions, or non
observance of the normal caution and care required for installation, operation, maintenance
and repair, even if not expressly stated, will be disclaimed by the manufacturer.
Precautions during maintenance or repair
1. Always use the correct safety equipment (such as safety glasses, gloves, safety shoes, etc.).
2. Use only the correct tools for maintenance and repair work.
3. Use only genuine spare parts.
4. All maintenance work shall only be undertaken when the machine has cooled down.
5. A warning sign bearing a legend such as "Work in progress; do not start" shall be attached to the
starting equipment.
6. Persons switching on remotely controlled machines shall take adequate precautions to ensure that
there is no one checking or working on the machine. To this end, a suitable notice shall be affixed to
the remote start equipment.
7. Before removing any component, effectively isolate the machine from all sources of under- and/or
overpressure and make sure that the pump system is at atmospheric pressure level.
8. Never use flammable solvents or carbon tetrachloride for cleaning parts. Take safety precautions
against toxic vapors of cleaning liquids.
9. Scrupulously observe cleanliness during maintenance and repair. Keep dirt away by covering the parts
and exposed openings with a clean cloth, paper or tape.
10. Never weld or perform any operation involving heat near the oil system. Oil tanks must be completely
purged, e.g. by steam cleaning, before carrying out such operations. Never weld on, or in any way
modify, pressure vessels.
11. Whenever there is an indication or any suspicion that an internal part of a machine is overheated, the
machine shall be stopped but no inspection covers shall be opened before sufficient cooling time has
elapsed; this to avoid the risk of spontaneous ignition of the oil vapor when air is admitted.
12. Never use a light source with open flame for inspecting the interior of a machine, pressure vessel, etc.
13. Make sure that no tools, loose parts or rags are left in or on the machine.
14. All regulating and safety devices shall be maintained with due care to ensure that they function
properly. They may not be put out of action.
15. Before clearing the machine for use after maintenance or overhaul, check that operating pressures,
temperatures and time settings are correct. Check that all control and shut-down devices are fitted and

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6996 0227 40 11
that they function correctly. If removed, check that the coupling guard of the vacuum pump drive shaft
has been reinstalled.
16. Every time the separator element is renewed, examine the discharge and the inside of the oil separator
vessel for carbon deposits; if excessive, the deposits should be removed.
17. Protect the motor, air filter, electrical and regulating components, etc. to prevent moisture from entering
them, e.g. when steam cleaning.
18. Make sure that all sound damping material and vibration dampers, e.g. damping material on the
bodywork and in the air inlet and outlet systems of the vacuum pump are in good condition. If
damaged, replace it by genuine material from the manufacturer to prevent the sound pressure level
from increasing.
19. Never use caustic solvents which can damage materials of the air net, e.g. polycarbonate bowls.
20. Faults or wearing of seals may cause oil lubricant leaks. Avoid dispersion in soil and pollution of other
materials.
Also consult sections Safety precautions during installation and Safety precautions during
operation.
These precautions apply to machinery processing or consuming air or inert gas. Processing
of any other gas requires additional safety precautions typical to the application which are not
included herein.
Some precautions are general and cover several machine types and equipment; hence some
statements may not apply to your machine.
Some precautions are general and cover several machine types and equipment; hence some
statements may not apply to your machine.

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12 6996 0227 40
2 General description
2.1 What is vacuum and how is flow rate understood
What is vacuum and how to denote
A vacuum is any pressure in a system that is below the ambient atmospheric pressure. It can be denoted
in absolute terms or in effective (gauge) terms:
mbar(a) –absolute pressure –denotes how much the pressure is above absolute zero vacuum.
(minus) mbar(e) –the effective or gauge pressure –denotes how much the pressure is below the local
atmospheric pressure.
Reference
Designation
1
Pressure
2
Absolute vacuum
3
Typical GHS pump working range (400 mbar(a) –10 mbar(a))
4
Atmospheric pressure
Atmospheric pressure at sea level is roughly 1 bar or 1000 mbar. A typical working range for the GHS
pumps is 400 mbar(a) to 10 mbar(a). From the illustration it can be seen clearly that this range is also
equivalent to -600 mbar(e) and -990 mbar(e).
It is important to understand which type of reference is required before selecting a pressure instrument for
measuring the vacuum. It must be noted that the distinction doesn't matter for a pressure difference (delta P;
e.g. pressure loss), since it is always the result of subtracting 2 pressures (whether stated as absolute or
effective pressures).
Flow rate definitions
There are 2 common but different ways to denote flow rate in vacuum. The first one is based on the
displacement or volumetric flow rate and the second one is based on the throughput or mass flow rate.
Atlas Copco vacuum pumps use volumetric flow rate to denote performance, the unit being Am³/hr.
Displacement/volumetric flow rate
For the relevant pressure range, when a GHS pump operates at quasi constant motor speed (rotations per
minute) and since the compression chambers have fixed dimensions, the same volume of air is pumped
from inlet to outlet with falling pressure level. Over the relevant pressure range, this makes the volumetric
flow rate quasi independent of the vacuum level. It is the expression of the flow rate inside the piping at the
governing vacuum level (Am³/hr), and always higher than the throughput in mass flow rate.

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6996 0227 40 13
Throughput in mass flow rate
Even if the volumetric flow rate is quasi unchanged with falling pressure level, the number of molecules in
that pumped volume is not. By definition: the deeper the vacuum, the lower the amount of molecules in the
same volume of air. This means that the mass flow will decrease with decreasing (absolute) pressure. It is
clear that a flow rate must be stated at a certain vacuum level when using this denotation.
2.2 Introduction
The GHS 350 VSD+up to GHS 900 VSD+are single-stage, oil-sealed screw vacuum pumps driven by an
electric motor.
The vacuum pumps are controlled by the Atlas Copco Elektronikon® Graphic regulator (ER).
The regulator is fitted to the front door. An electric cabinet (1) comprising fuses, transformers, relays, etc. is
located behind this door.
The vacuum pumps use VSD (Variable Speed Drive) technology. This means: automatic adjustment of the
motor speed, depending on the process demand.
The vacuum pumps are air-cooled and are enclosed in a sound-insulated bodywork.
Front view

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14 6996 0227 40
Open view front
Open view back
Reference
Name
AF
Air intake filter
Co
Oil cooler
E
Element
ER
Elektronikon®Graphiccontroller
FN
Cooling fan
DM
Drive motor
OF
Oil filter
OT
Oil separator tank
S3
Emergencystop button
1
Electric cabinet
VC
Vacuum control valve

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6996 0227 40 15
Reference
Name
IC
Inletconnection
BV
Thermostatic bypass valve
DC
Dischargeconnection
CE
Cable entry
2.3 Flow diagram
Air flow
Air comes in through air intake filter (AF) and Vacuum Control Valve (VC) and is displaced by the
vacuum pump element (E).
A mixture of air and oil flows into the oil separator tank (OT).
After passing the air/oil separator filter, clean air, conditioned to a few parts per million, is discharged
through the outlet.
Oil system
The oil separator tank (OT) removes most of the oil from the air/oil mixture by centrifugal action. The oil
separator (OS) removes the remaining oil. The oil collects in the lower part of the oil separator tank
(OT) which serves as oil tank.
The oil system has a thermostatic bypass valve (BV).When the oil temperature is below 83 °C (181 °F)
(87°C (189°F) for optional high water handling capacity versions), the bypass valve shuts off the oil
supply from the oil cooler (Co).
Air pressure forces the oil from oil separator tank through the oil filter (OF). The oil cooler (Co) is
bypassed. When the oil temperature has increased up to 83 °C (181 °F) (87°C (189° F) for optional
high water handling capacity versions), bypass valve (BV) starts opening the supply from the oil cooler
(Co). At approx. 95°C (203°F) (104°C (219°F) for optional high water handling capacity versions), all

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16 6996 0227 40
the oil flows through the oil cooler. The filtered oil flows into the vacuum pump element (E).
Cooling
The cooling system has an oil cooler (Co).
The fan (FN) blows air over the coolers. This fan is set to run on or off, depending on the operating
conditions, according to a specific algorithm.
2.4 Condensatesystem
When discharge piping is used, water in the discharge air can condense in the piping and is accumulated
in the collector of the outlet pipe, where a drain point (Dr) is available.
When the pump leaves the factory, this drain point is sealed with a threaded plug, but can be exchanged
by a G1/4" connector with tube to drain the condensate. Preventing condensate collection in the oil
separator will extend oil life.
Consult local regulations, which are applicable for water drainage.
2.5 Regulating system
Description
If the vacuum process demand is less than the throughput of the vacuum pump, the vacuum pressure
decreases. When the pressure is lower than the set-point (desired vacuum pressure), the regulator
decreases the motor speed.
If the vacuum pressure decreases and the motor operates at minimum speed, the regulator stops the
motor. When the motor is stopped automatically and the vacuum pressure comes to the set-point, the
regulator starts the motor again.
Turbo version
The regulation system of the Turbo version is designed to handle fast cycling duties. When the vacuum
pressure reaches the set-point, the regulator will keep the motor running at increased speed for an
adjustable time before the regulator decreases the motor speed.

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6996 0227 40 17
2.6 Electrical system
Electric components
The electrical system has following components:
Electrical cabinet (typical example)
Reference
Description
T1
Transformer
Q15
Circuit breaker
Q1
Circuit breaker
K15
Contactor
Z1
EMC filter
U1
Frequencyconverter
Electrical diagrams
You can find the complete electrical diagram inside the electric cabinet.

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18 6996 0227 40
3 Elektronikon® Graphic controller
3.1 Elektronikon® Graphic controller
Control panel
Display of the Elektronikon® Graphic controller
Introduction
The Elektronikon® controller has following functions:
•Controlling the vacuum pump
•Protecting the vacuum pump
•Monitoring components subject to service
•Automatic restart after voltage failure (made inactive)
Automatic control of the vacuum pump operation
The controller maintains the pressure within programmable limits by automatically adapting the motor
speed. A number of programmable settings, e.g. the set point, the minimum stop time and the maximum
number of motor starts and several other parameters are hereby taken into account.
The controller stops the vacuum pump whenever possible to reduce the power consumption and restarts it
automatically when the pressure decreases. For High Water Handling Capability pumps, the pump is
equipped with a purge cycle which prevents and removes condensed water in the sealing oil.
A number of time based automatic start/stop command may be programmed. Take into
account that a start command will be executed (if programmed and activated), even after
manually stopping the vacuum pump.

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6996 0227 40 19
Protecting the Vacuum pump
Shut-down
Several sensors are provided on the vacuum pump. If one of the measurements succeeds the
programmed shut down level, the vacuum pump will be stopped. This will be indicated on display (1) and
general alarm LED (2) will blink.
Remedy the trouble and reset the message. See also the Inputs menu.
Before remedying, consult the Safety precautions.
Shut-down warning
A shut-down warning level is a programmable level below the shut-down level.
If one of the measurements succeeds the programmed shut-down warning level, a message will appear on
display(1) and general alarm LED(2) will light up, to warn the operator that the shut-down warning level is
exceeded.
The message disappears as soon as the warning condition disappears.
Warning
A warning message will appear if:
- Element outlet temperature is too high
- Pump discharge pressure is too high
- Purge cycle was not successful (temperature not reached within requested time)
Service warning
A number of service operations are grouped (called Service Plans). Each Service Plan has a programmed
time interval. If a time interval is exceeded, a message will appear on display (1) to warn the operator to
carry out the service actions belonging to that Service Plan.
Automatic restart after voltage failure
The regulator has a built-in function to automatically restart the vacuum pump if the voltage is restored
after voltage failure. For vacuum pumps leaving the factory, this function is made inactive. If desired, the
function can be activated. Consult the Atlas Copco Customer Center.
If activated and provided the regulator was in the automatic operation mode, the vacuum
pump will automatically restart if the supply voltage to the module is restored.

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20 6996 0227 40
3.2 Control panel
Elektronikon regulator
Elektronikon regulator
Reference
Designation
Function
1
Display
Shows the vacuum pump operating condition and a number of icons to
navigate through the menu.
2
Pictograph
Automatic operation
3
Pictograph
General alarm
4
General alarm
LED
Flashes if a shut-down warning condition exists.
5
Pictograph
Service
6
Service LED
Lights up if service is needed
7
Automatic
operation LED
Indicates that the regulator is automatically controlling the vacuum pump.
8
Voltage on LED
Indicates that the voltage is switched on.
9
Pictograph
Voltage on
10
Enter key
Key to select the parameter indicated by the horizontal arrow. Only the
parameters followed by an arrow pointing to the right can be modified.
11
Escape key
To go to previous screen or to end the current action
12
Scroll keys
Keys to scroll through the menu.
13
Stop button
Button to stop the vacuum pump LED (7) goes out.
14
Start button
Button to start the vacuum pump LED (7) lights up indicating that the
Elektronik
on regulator is operative.