Atlas Copco ZT 55 VSD User manual

Instruction book
API797429
ZT 55 VSD

Atlas Copco
ZT 55 VSD
API797429
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.
2021 - 05
www.atlascopco.com

Table of contents
1 Additional safety precautions....................................................................................... 5
1.1 SAFETY ICONS...................................................................................................................................5
1.2 GENERAL SAFETY PRECAUTIONS............................................................................................................5
1.3 SAFETY PRECAUTIONS DURING INSTALLATION...........................................................................................6
1.4 SAFETY PRECAUTIONS DURING OPERATION..............................................................................................7
1.5 SAFETY PRECAUTIONS DURING MAINTENANCE OR REPAIR........................................................................... 9
1.6 DISMANTLING AND DISPOSAL...............................................................................................................10
2 General description......................................................................................................12
2.1 INTRODUCTION.................................................................................................................................12
2.2 AIR FLOW....................................................................................................................................... 13
2.3 CONDENSATE DRAIN SYSTEM..............................................................................................................14
2.4 OIL SYSTEM.................................................................................................................................... 15
2.5 COOLING SYSTEM.............................................................................................................................16
2.6 ELECTRICAL SYSTEM.........................................................................................................................16
3 Elektronikon™ Touch controller................................................................................. 18
3.1 CONTROLLER...................................................................................................................................18
3.2 CONTROL PANEL.............................................................................................................................. 20
3.3 ICONS USED.................................................................................................................................... 21
3.4 MAIN SCREEN..................................................................................................................................25
3.5 QUICK ACCESS SCREEN.....................................................................................................................26
3.6 MENU SCREEN.................................................................................................................................27
3.7 DATA MENU.....................................................................................................................................29
3.8 SERVICE MENU................................................................................................................................ 31
3.9 WEEK TIMER MENU...........................................................................................................................33
3.10 EVENT HISTORY MENU.......................................................................................................................34
3.11 MACHINE SETTINGS MENU..................................................................................................................35
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3.12 CONTROLLER SETTINGS MENU.............................................................................................................38
3.13 ACCESS LEVEL.................................................................................................................................41
4 Installation.....................................................................................................................43
4.1 INSTALLATION WARNINGS................................................................................................................... 43
4.2 DIMENSION DRAWINGS.......................................................................................................................44
4.3 INSTALLATION PROPOSAL................................................................................................................... 46
4.4 ELECTRIC CONNECTIONS....................................................................................................................48
4.5 PICTOGRAPHS................................................................................................................................. 51
5 Operating instructions................................................................................................. 54
5.1 OPERATION INTRODUCTION.................................................................................................................54
5.2 INITIAL START-UP .............................................................................................................................54
5.3 STARTING.......................................................................................................................................56
5.4 DURING OPERATION..........................................................................................................................57
5.5 STOPPING.......................................................................................................................................59
5.6 TAKING OUT OF OPERATION................................................................................................................59
6 Maintenance..................................................................................................................60
6.1 MAINTENANCE WARNINGS.................................................................................................................. 60
6.2 PREVENTIVE MAINTENANCE SCHEDULE OF THE COMPRESSOR.................................................................... 60
6.3 SERVICE KITS.................................................................................................................................. 61
6.4 SERVICE AGREEMENTS...................................................................................................................... 61
6.5 SERVICE PLAN................................................................................................................................. 62
6.6 OIL SPECIFICATIONS..........................................................................................................................62
6.7 STORAGE AFTER INSTALLATION........................................................................................................... 62
7 Servicing procedures...................................................................................................64
7.1 AIR FILTER (AF)..............................................................................................................................64
7.2 OIL AND OIL FILTER CHANGE...............................................................................................................65
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7.3 ADJUSTMENT OF THE INTERCOOLER PRESSURE...................................................................................... 66
7.4 MOTOR GREASING............................................................................................................................66
7.5 SAFETY VALVES............................................................................................................................... 66
8 Faults and remedies.....................................................................................................68
9 Principal data................................................................................................................ 70
9.1 READINGS ON DISPLAY...................................................................................................................... 70
9.2 ELECTRIC CABLE SIZE....................................................................................................................... 71
9.3 SETTINGS OF SAFETY VALVES............................................................................................................. 75
9.4 OVERLOAD RELAY AND FUSE SETTINGS.................................................................................................75
9.5 REFERENCE CONDITIONS................................................................................................................... 75
9.6 LIMITATIONS.................................................................................................................................... 75
9.7 COMPRESSOR DATA..........................................................................................................................76
10 Instructions for use...................................................................................................... 77
11 Pressure equipment directives................................................................................... 78
12 Documentation..............................................................................................................79
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1 Additional safety precautions
1.1 Safety icons
Explanation
Danger to life
Warning
Important note
1.2 General safety 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. The personnel should apply safe working practices by use of
personal protection equipment, appropriate tools and defined procedures.
4. The compressor is not considered capable of producing air of breathing quality. For air of
breathing quality, the compressed air must be adequately purified according to the
applicable legislation and standards.
5. Before any maintenance, repair work, adjustment or any other non-routine checks:
• Stop the machine
• Press the emergency stop button
• Switch off the voltage
• Depressurize the machine
• 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!
6. Never play with compressed air. Do not apply the air to your skin or direct an air stream at
people. Never use the air to clean dirt from your clothes. When using the air to clean
equipment, do so with extreme caution and wear eye protection.
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 prohibited to walk or stand on the unit or on its components.
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9. The Variable Speed Drive is equipped with a Safe Torque Off function, triggered by the
emergency stop button. The Safe Torque Off function has the immediate effect that the drive
can not supply any torque-generating energy. The drive is reliably torque-free. This state is
monitored internally in the drive.
The Safe Torque Off function does not disconnect the voltage of the main and auxiliary
circuits from the drive. Maintenance work on electrical parts of the drive or the motor can
only be carried out after isolating the drive system from the main supply!
10. If compressed air is used in the food industry and more specifically for direct food contact, it
is recommended, for optimal safety, to use certified Class 0 compressors in combination
with appropriate filtration depending on the application. Please contact your customer center
for advice on specific filtration.
11. The service switch should only be operated by a trained service specialist from the
manufacturer.
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. In case the device is a compressor, 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. Care must
be taken to minimize the entry of moisture at the inlet air.
4. Any blanking flanges, plugs, caps and desiccant bags must be removed before connecting
the pipes.
5. Air hoses must be of correct size and suitable for the working pressure. Never use frayed,
damaged or worn hoses. Distribution pipes and connections must be of the correct size and
suitable for the working pressure.
6. In case the device is a compressor, the aspirated air must be free of flammable fumes,
vapors and particles, e.g. paint solvents, that can lead to internal fire or explosion.
7. In case the device is a compressor, arrange the air intake so that loose clothing worn by
people cannot be drawn in.
8. Ensure that the discharge pipe from the compressor to the aftercooler or air net is free to
expand under heat and that it is not in contact with or close to flammable materials.
9. No external force may be exerted on the air outlet valve; the connected pipe must be free of
strain.
10. If remote control is installed, the machine must bear a clear sign stating: DANGER: This
machine is remotely controlled and may start without warning.
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The operator has to make sure that the machine is stopped and 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 on or off 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.
11. 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 compressor air inlet or
cooling air inlet.
12. 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 compressor.
13. 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.
14. In multiple compressor systems, manual valves must be installed to isolate each
compressor. Non-return valves (check valves) must not be relied upon for isolating pressure
systems.
15. Never remove or tamper with the safety devices, guards or insulation fitted on the machine.
Every pressure vessel or auxiliary installed outside the machine to contain air above
atmospheric pressure must be protected by a pressure relieving device or devices as
required.
16. 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.
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.
18. If the ground is not level or can be subject to variable inclination, consult the manufacturer.
19. If the device is a dryer and no free extinguishing system is present in the air net close to the
dryer, safety valves must be installed in the vessels of the dryer.
Also consult the following safety precautions: Safety precautions during operation and
Safety precautions during maintenance.
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 machine during operation.
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2. Use only the correct type and size of hose end fittings and connections. When blowing
through a hose or air line, ensure that the open end is held securely. A free end will whip
and may cause injury. 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,
vapors 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 machines 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
• No leaks occur
• 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
• Air cooling filters of the electrical cabinet are not clogged
9. If warm cooling air from compressors 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. On water-cooled compressors using open circuit cooling towers, protective measures must
be taken to avoid the growth of harmful bacteria such as Legionella pneumophila bacteria.
11. Do not remove any of, or tamper with, the sound-damping material.
12. Never remove or tamper with the safety devices, guards or insulations fitted on the machine.
Every pressure vessel or auxiliary installed outside the machine to contain air above
atmospheric pressure shall be protected by a pressure relieving device or devices as
required.
13. Yearly inspect the air receiver. Minimum wall thickness as specified in the instruction book
must be respected. Local regulations remain applicable if they are more strict.
Also consult following safety precautions: Safety precautions during installation and
Safety precautions during maintenance.
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.
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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 for maintenance or repair. The manufacturer will disclaim all
damage or injuries caused by the use of non-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. Close the compressor air outlet valve and depressurize the compressor before connecting
or disconnecting a pipe.
8. Before removing any pressurized component, effectively isolate the machine from all
sources of pressure and relieve the entire system of pressure.
9. Never use flammable solvents or carbon tetrachloride for cleaning parts. Take safety
precautions against toxic vapors of cleaning liquids.
10. Scrupulously observe cleanliness during maintenance and repair. Keep dirt away by
covering the parts and exposed openings with a clean cloth, paper or tape.
11. 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.
12. 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.
13. Never use a light source with open flame for inspecting the interior of a machine, pressure
vessel, etc.
14. Make sure that no tools, loose parts or rags are left in or on the machine.
15. 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.
16. 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 that they function correctly. If removed, check that the coupling guard
of the compressor drive shaft has been reinstalled.
17. Every time the separator element is renewed, examine the discharge pipe and the inside of
the oil separator vessel for carbon deposits; if excessive, the deposits should be removed.
18. Protect the motor, air filter, electrical and regulating components, etc. to prevent moisture
from entering them, e.g. when steam cleaning.
19. 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 compressor, is in good condition.
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If damaged, replace it by genuine material from the manufacturer to prevent the sound
pressure level from increasing.
20. Never use caustic solvents which can damage materials of the air net, e.g. polycarbonate
bowls.
21. Only if applicable, the following safety precautions are stressed when handling
refrigerant:
• Never inhale refrigerant vapors. Check that the working area is adequately ventilated; if
required, use breathing protection.
• Always wear special gloves. In case of refrigerant contact with the skin, rinse the skin
with water. If liquid refrigerant contacts the skin through clothing, never tear off or
remove the latter; flush abundantly with fresh water over the clothing until all refrigerant
is flushed away; then seek medical first aid.
Also consult following safety precautions: 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.
1.6 Dismantling and disposal
Dismantling
Once the end of life of the machine is reached, please follow next steps:
1. Stop the machine.
2. Check all safety precautions mentioned in the previous chapters to secure safe handling
(e.g. LOTO, cool-down, depressurize, discharge, ...).
3. Separate the harmful from the safe components (e.g. drain oil from oil containing parts).
4. Refer to the disposal topic mentioned below.
Disposal of electrical and electronic appliances (WEEE)
This equipment falls under the provisions of the European Directive 2012/19/EU on waste
electrical and electronic appliances (WEEE) and may not be disposed as unsorted waste.
The equipment is labelled in accordance with the European Directive 2012/19/EU with the
crossed-out wheelie bin symbol.
At the end of life-time of the electric and electronic equipment (EEE) it must be taken to separate
collection.
For more information check with your local waste authority, customer center or distributor.
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Disposal of other used material
Used filters or any other used material (e.g. filter bags, filter media, desiccant, lubricants,
cleaning rags, machine parts, etc.) must be disposed of in an environmentally friendly and safe
manner, and in line with the local recommendations and environmental legislation.
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2 General description
2.1 Introduction
General description
The VSD (Variable Speed Drive) machines are two-stage rotary tooth compressors, driven by an
electric motor. The compressors deliver oil-free air. ZT are air-cooled and ZR are water-cooled.
By continuously matching the speed of the drive motor to the air demand, the VSD compressor
optimizes energy consumption and reduces the operating pressure band.
The compressors are enclosed in a sound-insulating bodywork.
The compressors are built up with following major components:
• Inlet silencer with integrated air filter (IS-AF)
• Load/no-load valve (UA)
• Low-pressure compressor element (El)
• Intercooler (Ci)
• High-pressure compressor element (Eh)
• Aftercooler (Ca)
• Electric motor (M1)
• Drive coupling
• Gear casing
•ElektronikonTM regulator (1)
• Safety valves (SVh)
All compressors are so-called WorkPlace Air System compressors, which means they operate at
a very low noise level.
General view
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AV Air outlet valve
S3 Emergency stop button
1ElektronikonTM regulator
3 Condensate drains
4 Converter cabinet
Front view, Pack
AV Outlet valve
Ca Aftercooler
Ci Intercooler
Co Oil cooler
Eh High-pressure compressor element
FC Oil filler plug
FN Cooling fan
M1 Compressor drive motor
M2 Fan motor
OF Oil filter (not shown)
SG Oil level sight glass
S3 Emergency stop button
1ElektronikonTM regulator
IS-AF Inlet silencer with integrated air filter
2.2 Air flow
Air drawn in through air filter (AF) and the open inlet valve of the unloader assembly (UA) is
compressed in the low-pressure compressor element (El) and discharged to the intercooler (Ci).
The cooled air is further compressed in the high-pressure compressor element (Eh) and
discharged through the pulsation damper (AS) and the aftercooler (Ca). A check valve (CV) is
provided downstream of the pulsation damper (AS). When the compressor switches to unload
operation, the air trapped in the pulsation damper and the high-pressure element is blown off via
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the blow-off silencer (US). The check valve (CV) prevents that compressed air downstream of the
check valve is blown off.
References used in all flow diagrams
(1) Air inlet (3) Oil flow (5) Air outlet (7) Refrigerant gas
(2) Air flow (4) Water flow (6) Refrigerant fluid
References used for the compressor
Ref. Description Ref. Description
AF Air filter AS Pulsation damper
IS Inlet silencer CV Check valve
US Blow-off silencer Ca Aftercooler with integrated drain collector
UA Unloader assembly EWDa Electronic drain, aftercooler
El Low-pressure compressor element OP Oil pump
Ci Intercooler with integrated drain collector GC Oil sump (gear casing)
EWDi Electronic drain, intercooler Co Oil cooler
Eh High-pressure compressor element OF Oil filter
FN1 Cooling fan (ZT) AV Air outlet valve
2.3 Condensate drain system
Figures: see section Air Flow.
Compressor
Two condensate traps are installed on the compressor itself: one downstream of the intercooler
to prevent condensate from entering the high-pressure compressor element (Eh), the other one
downstream of the aftercooler to prevent condensate from entering the air outlet pipe.
On ZT, the condensate traps are integrated in the intercooler and the aftercooler outlet collector
and are connected to a no-loss electronic water drain (EWDi and EWDa).
Electronic water drains (EWD)
The condensate is collected in the electronic water drains. A sensor continuously measures the
liquid level. As soon as the collector is filled up to a certain level, the outlet opens, discharging
the condensate. When the collector has been emptied, the outlet closes quickly without wasting
compressed air.
Testing the electronic water drains can be done by pressing the test button (1) on top of the
drain. Check that the valve opens for condensate discharge.
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Electronic water drains, typical example
The drains are connected to the side panel of the compressor as shown in the next figure:
Condensate drain connections
Ref. Designation Ref. Designation
1 Automatic drain, aftercooler 5 Automatic drain, dryer (FF units)
2 Automatic drain, intercooler 6 Manual drain, dryer (FF units)
3 Manual drain, intercooler 7 Manual drain, regeneration cooler IMD
(FF units with IMD dryer)
4 Manual drain, aftercooler
2.4 Oil system
Figures: see section air flow.
Oil is circulated by pump (OP) from the sump of the gear casing through oil cooler (Co) and oil
filter (OF) towards the bearings and the gears.
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The oil system is equipped with a valve that opens if the oil pressure rises above a given value.
The valve is located before the oil filter housing.
2.5 Cooling system
Figures: see section Air flow.
ZT compressors are provided with an air-cooled oil cooler (Co), an intercooler (Ci) and an
aftercooler (Ca). An electric motor driven fan (FN1) generates the cooling air.
2.6 Electrical system
Main components
The electrical system mainly includes:
•ElektronikonTM regulator
• Emergency stop button
• Converter cabinet including the frequency converter
• Compressor drive motor (M1)
• Pressure and temperature sensors
• Solenoid valves
ElektronikonTM regulator
The detailed functioning of the ElektronikonTM regulator is explained in the next chapter.
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Converter cabinet
F1/2 Fuses K16 Contactor
F7/8/9 Fuses Q15 Fan motor protection
K20 Main contactor T1 Transformer
K11 Contactor E1 ElektronikonTM regulator
K15 Contactor S3 Emergency stop button
U1 Frequency converter Z1 RFI filter
L1 Inductor
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3 Elektronikon™ Touch controller
3.1 Controller
The Elektronikon™ Touch controller
Introduction
The controller has the following functions:
• Controlling the unit
• Protecting the unit
• Monitoring components subject to service
• Automatic Restart After Voltage Failure (ARAVF)
Automatic control of the unit
The controller maintains the net pressure between programmable limits by automatically loading
and unloading the unit (fixed speed units) or by adapting the motor speed (units with frequency
converter).
A number of programmable settings, e.g. the unloading and loading pressures (for fixed speed
units), the setpoint (for units with frequency converter), the minimum stop time, the maximum
number of motor starts and several other parameters are taken into account.
The controller stops the unit whenever possible to reduce the power consumption and restarts it
automatically when the net pressure decreases. If the expected unloading period is too short, the
unit is kept running to prevent too short standstill periods.
It is possible to program a number of time-based commands for automatic start/stop.
Take into account that a start command will be executed (if programmed and activated),
even after manually stopping the unit.
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