Mark MSU 15 User manual

Mark
Oil-injected rotary screw compressors
MSU 11, MSU 15, MSU 20
Instruction book

Mark
Oil-injected rotary screw compressors
MSU 11, MSU 15, MSU 20
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 - 06
No. 2920 7201 40
www.mark-compressors.com

Table of contents
1 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........................................................................... 8
1.6 DISMANTLING AND DISPOSAL...............................................................................................................10
2 General description......................................................................................................11
2.1 INTRODUCTION.................................................................................................................................11
2.2 AIR FLOW....................................................................................................................................... 14
2.3 OIL SYSTEM.................................................................................................................................... 16
2.4 COOLING SYSTEM.............................................................................................................................17
2.5 REGULATING SYSTEM........................................................................................................................ 18
2.6 CONTROL PANEL ............................................................................................................................. 19
2.7 ELECTRICAL SYSTEM.........................................................................................................................20
2.8 PROTECTION OF THE COMPRESSOR......................................................................................................23
2.9 AIR DRYER......................................................................................................................................24
3 Controller.......................................................................................................................25
3.1 CONTROLLER...................................................................................................................................25
3.2 CONTROL PANEL.............................................................................................................................. 26
3.3 ICONS USED ON THE DISPLAY..............................................................................................................27
3.4 MAIN SCREEN..................................................................................................................................28
3.5 MAIN FUNCTION............................................................................................................................... 29
3.6 SHUTDOWN WARNING........................................................................................................................31
3.7 SHUTDOWN.....................................................................................................................................32
3.8 SERVICE WARNING............................................................................................................................34
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3.9 SCROLLING THROUGH ALL SCREENS.....................................................................................................36
3.10 CALLING UP RUNNING HOURS..............................................................................................................37
3.11 CALLING UP MOTOR STARTS............................................................................................................... 38
3.12 CALLING UP MODULE HOURS...............................................................................................................38
3.13 CALLING UP LOADING HOURS.............................................................................................................. 39
3.14 CALLING UP LOAD SOLENOID VALVE..................................................................................................... 39
3.15 CALLING UP/RESETTING THE SERVICE TIMER.......................................................................................... 40
3.16 CALLING UP/MODIFYING PRESSURE BAND SELECTION............................................................................... 40
3.17 CALLING UP/MODIFYING PRESSURE BAND SETTINGS.................................................................................41
3.18 CALLING UP/MODIFYING THE UNIT OF TEMPERATURE................................................................................41
3.19 CALLING UP/MODIFYING THE UNIT OF PRESSURE.....................................................................................41
3.20 CALLING UP/MODIFYING BACKLIGHT TIME...............................................................................................42
3.21 ACTIVATING AUTOMATIC RESTART AFTER VOLTAGE FAILURE...................................................................... 42
3.22 KEYBOARD LOCK..............................................................................................................................43
4 Installation.....................................................................................................................44
4.1 INSTALLATION PROPOSAL................................................................................................................... 44
4.2 DIMENSION DRAWINGS.......................................................................................................................47
4.3 ELECTRICAL CONNECTIONS ................................................................................................................48
4.4 PICTOGRAPHS................................................................................................................................. 51
5 Operating instructions................................................................................................. 53
5.1 INITIAL START-UP..............................................................................................................................53
5.2 STARTING....................................................................................................................................... 56
5.3 STOPPING.......................................................................................................................................58
5.4 TAKING OUT OF OPERATION................................................................................................................59
6 Maintenance..................................................................................................................61
6.1 PREVENTIVE MAINTENANCE SCHEDULE..................................................................................................61
6.2 DRIVE MOTOR .................................................................................................................................63
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6.3 OIL SPECIFICATIONS..........................................................................................................................63
6.4 OIL, FILTER AND SEPARATOR CHANGE ................................................................................................. 63
6.5 STORAGE AFTER INSTALLATION........................................................................................................... 65
6.6 SERVICE KITS.................................................................................................................................. 65
7 Adjustments and servicing procedures..................................................................... 66
7.1 AIR FILTER......................................................................................................................................66
7.2 COOLERS....................................................................................................................................... 67
7.3 SAFETY VALVE ................................................................................................................................67
7.4 BELT SET EXCHANGE AND TENSIONING ................................................................................................ 69
8 Problem solving............................................................................................................72
9 Technical data...............................................................................................................76
9.1 ELECTRIC CABLE SIZE....................................................................................................................... 76
9.2 SETTINGS FOR OVERLOAD RELAY AND FUSES.........................................................................................76
9.3 REFERENCE CONDITIONS AND LIMITATIONS............................................................................................ 77
9.4 COMPRESSOR DATA..........................................................................................................................77
10 Instructions for use...................................................................................................... 80
11 Guidelines for inspection.............................................................................................81
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1 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. 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.
10. 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.
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.
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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.
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.
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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.
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.
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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.
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.
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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.
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
Introduction
MSU 11, MSU 15 and MSU 20 are air-cooled, single-stage, oil-injected screw compressors,
driven by an electric motor.
The compressors are enclosed in sound-insulating bodywork.
An easy-to-operate control panel is provided, including the start/stop switch and the emergency
stop button. A cabinet housing the controller, pressure sensor and motor starter is integrated into
the bodywork.
Floor-mounted model
The compressor is installed directly on the floor.
Floor-mounted units are available without dryer only.
Tank-mounted model
MSU 11, MSU 15 and MSU 20 tank-mounted units are supplied with an air receiver of 500 l (132
US gal / 110 Imp gal / 17.50 cu.ft).
Tank-mounted units are available with or without dryer.
Front view, tank-mounted with dryer
Reference Designation
1 Electric cabinet
ER Controller
S3 Emergency stop button
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Reference Designation
AO Air outlet
AR Air receiver
Dm1 Manual condensate drain
DR Dryer
D Dewpoint indicator (only on units with dryer)
Front open view, tank-mounted
Reference Designation
Co Oil cooler
OF Oil filter
OS Oil separator
OT Oil separator tank
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Rear open view, tank-mounted
Air filter
Reference Designation
E Compressor element
AF Air filter
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2.2 Air flow
Air flow, Tank-mounted
Air drawn through filter (AF) and open inlet valve (IV) into compressor element (E) is
compressed. Compressed air and oil flow into oil separator/tank (OT). The air is discharged via
minimum pressure valve (Vp) towards the air outlet (AO).
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Air flow, Tank-mounted with dryer
Air drawn through filter (AF) and open inlet valve (IV) into compressor element (E) is
compressed. Compressed air and oil flow into oil separator/tank (OT). The air is discharged via
minimum pressure valve (Vp), air receiver (AR) and air dryer (DR) towards the air outlet (AO).
The unit has 2 filters (FT). The G filter (coarse) is located upstream the dryer, the C filter (fine) is
located downstream the dryer.
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2.3 Oil system
Oil system
Oil system, units with dryer
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Air pressure in the oil separator tank (OT) forces the oil from the tank to compressor element (E)
via oil cooler (Co) and oil filter (OF). Compressed air and oil flow into oil separator/tank (OT)
where most of the oil is separated from the air by centrifugal action. The remaining oil is removed
by oil separator (OS) and returns to the oil circuit via a separate line. The minimum pressure
valve (Vp - see section Air flow) ensures a minimal pressure in the tank, required for oil
circulation under all circumstances.
The oil system is fitted with a by-pass valve (BV). When the oil temperature is below the set-point
of the valve, the by-pass valve shuts off the oil supply from oil cooler. The by-pass valve starts
opening the supply from cooler (Co) when the oil temperature exceeds the setting of the valve.
The setting of the by-pass valve depends on the model. See section Compressor data.
2.4 Cooling system
Cooling system
The cooling system comprises oil cooler (Co) and fan (FN). The fan, mounted directly onto the
motor shaft, generates the cooling air in order to cool the oil and the internal parts of the
compressor.
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Cooling system, units with dryer
The cooling system of the version with dryer comprises oil cooler (Co), air receiver (AR) and fan
(FN).
The dryer (DR) has a separate cooling fan and an automatic condensate drain (see also section
Air dryer).
2.5 Regulating system
Detail view of unloader assembly (UA)
The main components of the regulating system are:
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