Mark MSU 11 User manual

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

Mark
Oil-injected 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, non-CE as well as UKCA labelled machines. It
meets the requirements for instructions specified by the applicable European directives
or UK statutory instruments as identified in the Declaration of Conformity.
May 2023
No. 2920 7201 41
www.mark-compressors.com

Table of contents
1 Safety precautions..........................................................................................................6
1.1 Safety icons................................................................................................................................6
1.2 General safety precautions.................................................................................................... 6
1.3 Safety precautions during installation................................................................................ 7
1.4 Safety precautions during operation.................................................................................... 8
1.5 Safety precautions during maintenance or repair.............................................................. 9
1.6 Dismantling and disposal........................................................................................................ 11
2 General description......................................................................................................12
2.1 Introduction............................................................................................................................. 12
2.2 Air flow..................................................................................................................................... 14
2.3 Oil system..................................................................................................................................15
2.4 Cooling system.........................................................................................................................15
2.5 Regulating system................................................................................................................... 16
2.6 Control panel ......................................................................................................................... 17
2.7 Electrical system.................................................................................................................... 17
2.8 Protection of the compressor............................................................................................. 19
3 Controller.......................................................................................................................21
3.1 Controller functions.............................................................................................................21
3.2 Control panel.......................................................................................................................... 24
3.3 Icons used................................................................................................................................. 25
3.4 Main screen...............................................................................................................................27
3.5 Warning..................................................................................................................................... 27
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3.6 Shutdown.................................................................................................................................. 28
3.7 Service warning....................................................................................................................... 31
3.8 Remote control....................................................................................................................... 31
3.9 Scrolling through screens...................................................................................................32
3.10 Calling up/ modifying pressure band settings................................................................. 32
3.11 Calling up running hours.......................................................................................................33
3.12 Calling up Software release.................................................................................................34
3.13 Calling up Bluetooth pairing/ discovery mode................................................................... 35
3.14 Advanced menu......................................................................................................................... 36
3.15 Service mode.............................................................................................................................36
3.16 Screen test...............................................................................................................................36
3.17 Calling up factory reset........................................................................................................37
3.18 Connectivity-Smartphone App............................................................................................... 37
4 Installation.....................................................................................................................41
4.1 Installation proposal............................................................................................................. 41
4.2 Dimension drawings................................................................................................................. 44
4.3 Electrical connections ......................................................................................................... 45
4.4 Pictographs.............................................................................................................................. 49
5 Operating instructions................................................................................................. 51
5.1 Initial start-up..........................................................................................................................51
5.2 Starting.....................................................................................................................................54
5.3 Stopping.....................................................................................................................................56
5.4 Taking out of operation..........................................................................................................57
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6 Maintenance..................................................................................................................58
6.1 Preventive maintenance schedule.........................................................................................58
6.2 Drive motor ..............................................................................................................................60
6.3 Oil specifications..................................................................................................................... 60
6.4 Oil, filter and separator change ......................................................................................... 60
6.5 C/G filter change.....................................................................................................................62
6.6 Storage after installation.................................................................................................... 64
6.7 Service kits............................................................................................................................... 64
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............................................................................................................... 74
9.1 Electric cable size...................................................................................................................74
9.2 Settings for overload relay and fuses...............................................................................75
9.3 Reference conditions and limitations.................................................................................. 75
9.4 Compressor data..................................................................................................................... 76
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10 Instructions for use...................................................................................................... 78
11 Guidelines for inspection.............................................................................................79
12 Pressure equipment directives................................................................................... 80
13 Declaration of conformity............................................................................................ 81
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1 Safety precautions
1.1 Safety icons
Danger: Indicates an imminently hazardous situation which, if not avoided, will result in
death or serious injury.
Warning: Indicates a potentially hazardous situation which, if not avoided, could result in
death or serious injury.
Notice: Indicates a potential situation which, if not avoided, might result in property damage
or in an undesirable result or state.
Note: Indicates important information.
1.2 General safety precautions
• The operator must employ safe working practices and observe all related work safety
requirements and regulations.
• If any of the following statements does not comply with the applicable legislation, the stricter of
the two shall apply.
• 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.
• 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.
• Before any maintenance, repair work, adjustment or any other non-routine checks, switch the
controller in service mode (see section Service mode), stop the compressor, press the
emergency stop button, switch off the voltage and depressurize the compressor. In addition, the
power isolating switch must be opened and locked. The process of locking, tagging and trying
to turn on the equipment to confirm it cannot operate is called Lock Out, Tag Out (LOTO).
Danger: 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!
• 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.
• The owner is responsible for maintaining the unit in safe operating condition. Parts and
accessories shall be replaced if unsuitable for safe operation.
• It is not allowed to walk or stand on the unit or on its components.
• 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.
• The service switch should only be operated by a trained service specialist from the
manufacturer.
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Safety precautions for the connectivity module
It is important to follow all regulations regarding the use of radio equipment, in particular regarding
the possibility of radio frequency (RF) interference. Please follow the safety advice given below
carefully.
• Respect restrictions on the use of radio equipment in fuel depots, chemical plants or other
explosive environments.
• Avoid operation close to inadequately protected personal medical devices such as hearing aids
and pacemakers. Consult the manufacturers of the medical device to determine if it is
adequately protected.
• Avoid operation close to other electronic equipment which may also cause interference if the
equipment is inadequately protected. Observe any warning signs and manufacturer
recommendations.
• Respect a distance from the human body of at least 20 cm (8 inch) during operation.
1.3 Safety precautions during installation
Warning: 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.
• 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.
• The unit is designed for indoor use. If the unit is installed outdoors, special precautions must be
taken. Consult your supplier.
• 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.
• Any blanking flanges, plugs, caps and desiccant bags must be removed before connecting the
pipes.
• 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.
• The aspirated air must be free of flammable fumes, vapors and particles, e.g. paint solvents,
that can lead to internal fire or explosion.
• Arrange the air intake so that loose clothing worn by people cannot be drawn in.
• Ensure that the discharge pipe from the compressor to the after-cooler or air net is free to
expand under heat and that it is not in contact with or close to flammable materials.
• No external force may be exerted on the air outlet valve; the connected pipe must be free of
strain.
• 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
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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.
• 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.
• 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.
• 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.
• 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.
• 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.
• 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.
• If the ground is not level or can be subject to variable inclination, consult the manufacturer.
• In an installation with multiple compressors, the outlet piping must be installed in such a way
that condensate cannot flow back into the compressor. See section Installation proposal.
Note: Also consult the following safety precautions: 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
Warning: 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.
• Never touch any piping or components of the machine during operation.
• 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.
• 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.
• Never operate the machine when there is a possibility of taking in flammable or toxic fumes,
vapors or particles.
• Never operate the machine below or in excess of its limit ratings.
• 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 and eye protection when opening a door.
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On machines without bodywork, wear ear protection in the vicinity of the machine.
• People staying in environments or rooms where the sound pressure level reaches or exceeds
80 dB(A) shall wear ear protectors.
• 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
• All pre-filters are not clogged
• 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.
• Do not remove any of, or tamper with, the sound-damping material.
• 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.
• 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.
Note: Also consult the following safety precautions: 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.
1.5 Safety precautions during maintenance or repair
Warning: 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.
• Always use the correct safety equipment (such as safety glasses, gloves, safety shoes, etc.).
• Use only the correct tools for maintenance and repair work.
• 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.
• All maintenance work shall only be undertaken when the machine has cooled down.
• A warning sign bearing a legend such as "Work in progress; do not start" shall be attached to
the starting equipment.
• 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.
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• Close the compressor air outlet valve and depressurize the compressor before connecting or
disconnecting a pipe.
• Before removing any pressurized component, effectively isolate the machine from all sources of
pressure and relieve the entire system of pressure. See section Maintenance.
• Never use flammable solvents or carbon tetrachloride for cleaning parts. Take safety
precautions against toxic vapors of cleaning liquids.
• Scrupulously observe cleanliness during maintenance and repair. Keep dirt away by covering
the parts and exposed openings with a clean cloth, paper or tape.
• 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.
• 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.
• Never use a light source with open flame for inspecting the interior of a machine, pressure
vessel, etc.
• Make sure that no tools, loose parts or rags are left in or on the machine.
• When replacing the air filter, make sure no dirt, dust, rags, tools or loose parts can fall in the air
inlet.
• 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.
• 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.
• 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.
• Protect the motor, air filter, electrical and regulating components, etc. to prevent moisture from
entering them, e.g. when steam cleaning.
• 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.
• Never use caustic solvents which can damage materials of the air net, e.g. polycarbonate
bowls.
•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.
• Protect hands to avoid injury from hot machine parts, e.g. during draining of oil.
• Be aware of eventual sharp edges on certain parts of the machine.
Note: Also consult the following safety precautions: Safety precautions during operation and
Safety precautions during maintenance or repair.
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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
The device must be disposed according to local regulations. The product is not designed for
refurbishing after finished lifecycle.
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, etc.).
3. Have trained personnel dismantle the installation.
4. Separate the harmful from the safe components (e.g. drain oil from parts containing oil).
5. Refer to the disposal topic 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) as well as under the UKCA Waste Electrical and Electronic
Equipment regulations 2013 and may not be disposed as unsorted waste.
The equipment is labelled in accordance with the European Directive 2012/19/EU and the UKCA
Waste Electrical and Electronic Equipment regulations 2013 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.
Figure 1: Front view, floor-mounted
Reference Description
1 Electric cabinet
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.
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Figure 2: Front view, tank-mounted with dryer
Reference Description
1 Electric cabinet
ER Controller
S3 Emergency stop button
AO Air outlet
AR Air receiver
Dm1 Manual condensate drain
DR Dryer
D Dew point indicator (only on units with dryer)
Figure 3: Front open view, tank-mounted
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Reference Description
Co Oil cooler
OF Oil filter
OS Oil separator
OT Oil separator tank
Figure 4: Rear open view, tank-mounted
Reference Description
E Compressor element
AF Air filter
2.2 Air flow
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2.3 Oil system
Figure 5: Without dryer
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
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2.5 Regulating system
Main components
Figure 6: Detail view of unloader assembly (UA)
The main components of the regulating system are:
• Unloader (UA), including inlet valve (IV) and unloading valve (UV).
• Loading solenoid valve (Y1).
• The controller that regulates the compressor based on the pressure settings and readings of
the pressure sensor.
Loading
As long as the working pressure is below the preset maximum value, the solenoid valve is
energized, allowing control air to the unloader: the inlet valve is completely open and the
compressor will run fully loaded (100% output).
Unloading
When the working pressure reaches the maximum limit, the solenoid valve is de-energized, venting
the control air: the inlet valve closes completely and the unloading valve opens completely. The
compressor will run unloaded (0% output).
The units are equipped with an intelligent controller that uses Delayed Second Stop (DSS)
algorithm to determine when to stop or restart the motor.
The compressor will automatically restart when the net pressure drops to the minimum limit.
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2.6 Control panel
Figure 7: Electric cabinet - Control panel
Reference Description
1 Electric cabinet
ER Controller
S3 Emergency stop button
2.7 Electrical system
The electrical system comprises the following components:
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Figure 8: Electric cubicle UL (DOL)
Figure 9: Electric cubicle UL (YD)
Reference Description
F1 Primary fuse, transformer of the control circuit
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