Atlas Copco LF 2 User manual

Atlas Copco
Industrial aluminium piston compressor
LF 2, LF 3, LF 5, LF 7, LF 10
Instruction book

Atlas Copco
Instruction aluminium pistion compressors
LF 2, LF 3, LF 5, LF 7, LF 10
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.
2012 - 05
No. 2920 7090 02
Replace No. 2920 7090 01
www.atlascopco.com

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Instruction book
Table of contents
1Safety precautions......................................................................................................................4
1.1 Safety icons.......................................................................................................................4
1.2 Safety precautions, general...............................................................................................4
1.3 Safety precautions during installation ...............................................................................4
1.4 Safety precautions during operation .................................................................................6
1.5 Safety precautions during maintenance or repair .............................................................7
2General description....................................................................................................................9
2.1 General description ...........................................................................................................9
2.2 Operation.........................................................................................................................14
2.3 Air flow.............................................................................................................................15
2.4 Regulating system...........................................................................................................20
3Installation..................................................................................................................................22
3.1 Dimension drawings........................................................................................................22
3.2 Installation instruction......................................................................................................36
3.3 Electrical Connections.....................................................................................................40
3.4 Settings of overload relay and fuses...............................................................................41
3.5 Cable sizes......................................................................................................................44
3.6 Pictographs......................................................................................................................44
4Operating Instructions ............................................................................................................45
4.1 Initial start –up.................................................................................................................45
4.2 Starting ............................................................................................................................45
4.3 Stopping...........................................................................................................................47
4.4 Taking out of operation....................................................................................................47

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4.5 Storage after installation..................................................................................................47
5Maintenance...............................................................................................................................49
5.1 Petrol engine maintenance..............................................................................................49
5.2 Preventive maintenance schedule ..................................................................................49
5.3 Service kits ......................................................................................................................50
5.4 Disposal of used material................................................................................................50
6Servicing and adjustment procedures................................................................................51
6.1 Unloader or check valve..................................................................................................51
6.2 Valves..............................................................................................................................51
6.3 Air filter.............................................................................................................................53
6.4 Adjustment MDR4 pressure switch .................................................................................53
6.5 Adjustment MDR3 pressure switch.................................................................................55
6.6 Adjustment of pilot valve on Trolley.................................................................................56
6.7 Safety valve.....................................................................................................................57
7Problem solving........................................................................................................................59
8Technical data............................................................................................................................61
8.1 Reference conditions.......................................................................................................61
8.2 Limitations........................................................................................................................61
8.3 Compressor data.............................................................................................................61
9Instructions for use..................................................................................................................64
10 Pressure Equipment Directive (PED) ..................................................................................65
11 Declaration of conformity.......................................................................................................66

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1 Safety precautions
1.1 Safety icons
Explanation
Danger for life
Warning
Important note
1.2 Safety precautions, general
General Precautions
1. The operator must employ safe working practices and observe all related work safety requirements and
regulations.
2. If any of the following statements does not comply with the applicable legislation, the stricter of the two
shall apply.
3. Installation, operation, maintenance and repair work must only be performed by authorized, trained,
specialized personnel.
4. The 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 dryer, press the
emergency stop button, switch off the voltage and depressurize the dryer. In addition, the power isolating
switch must be opened and locked.
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 dryer in safe operating condition. Parts and accessories shall
be replaced if unsuitable for safe operation.
8. It is not allowed to walk or stand on the roof of the compressor canopy.
1.3 Safety precautions during installation
All responsibility for any damage or injury resulting from neglecting these precautions, or
non-observance of the normal precaution and care required for installation, operation,
maintenance and repair, even if not expressly stated, will be disclaimed by the manufacturer.

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Precautions during installation
1. The dryer must only be lifted using suitable equipment and 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. Place the dryer 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.
3. Any blanking flanges, plugs, caps or desiccant bags must be removed before connecting the pipes.
4. 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.
5. The aspirated air must be free of flammable fumes, vapours and particles, e.g. paint solvents, that can lead
to internal fire or explosion.
6. Arrange the air intake so that loose clothing worn by people cannot be sucked in.
7. Ensure that all piping is free to expand under heat and that it is not in contact with or close to flammable
materials.
8. No external force may be exerted on the air outlet valve. The connected pipe must be free of strain.
9. 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 that the isolating switch is open and locked
before any maintenance or repair. As a further safeguard, 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 starting equipment.
10. The machines must be installed in such a way that an adequate flow of cooling air is available and that
the air from the exhaust does not recirculate to the compressor air inlet or cooling air inlet..
11. 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.
12. 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.
13. 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.
14. 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.
15. Pipework or other parts with a temperature in excess of 80˚C (176˚F) and which may be accidentally
touched by personnel during normal operation must be guarded or insulated. Other high-temperature piping
must be clearly marked.
16. If the ground is not level or can be subject to variable inclinations, consult the manufacturer.
Also consult 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.

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1.4 Safety precautions during operation
All responsibility for any damage or injury resulting from neglecting these precautions, or
non-observance of the normal precaution and care required for installation, operation,
maintenance and repair, even if not expressly stated, will be disclaimed by the manufacturer.
Precautions during operation
1. 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.
2. 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.
3. Never operate the machine when there is a possibility of taking in flammable or toxic fumes, vapours or
particles.
4. Never operate the machine below or in excess of its limit ratings.
5. People staying in environments or rooms where the sound pressure level reaches or exceeds 90 dB(A) shall
wear ear protectors.
6. Periodically check that:
All guards are in place and securely fastened
All hoses and/or pipes inside the machine are in good condition, secure and not rubbing
There are no leaks
All fasteners are tight
All electrical leads are secure and in good order
Safety valves and other pressure-relief devices are not obstructed by dirt or paint
Air outlet valve and air net, i.e. pipes, couplings, manifolds, valves, hoses, etc. are in good condition, free
of wear or abuse
7. If warm cooling air from dryers is used in air heating systems, e.g. to warm up a working area, take
precautions against air pollution and possible contamination of the breathing air.
8. Do not remove any of, or tamper with, the sound-damping material.
9. 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.
Also consult following safety precautions: Safety precautions during installation and Safety
precautions during maintenance or repair.
These precautions apply to machinery processing or consuming air or inert gas. Processing
of any other gas requires additional safety precautions typical to the application which are
not included herein.
Some precautions are general and cover several machine types and equipment; hence
some statements may not apply to your machine.

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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 precaution 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 wear safety glasses.
2. Use only the correct tools for maintenance and repair work.
3. Use only genuine spare parts.
4. All maintenance work shall only be undertaken when the machine has cooled down.
5. A warning sign stating "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 dryer air outlet valve 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 vapours 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. Protect the motor, electrical and regulating components, etc. to prevent moisture from entering them, e.g.
when steam-cleaning.
18. Make sure that all sound-damping material and vibration dampers, e.g. damping material on the bodywork
and in the air inlet and outlet systems of the compressor, are in good condition. If damaged, replace it by
genuine material from the manufacturer to prevent the sound pressure level from increasing.
19. Never use caustic solvents which can damage materials of the air net, e.g. polycarbonate bowls.
20. 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.
21. Protect hands to avoid injury from hot machine parts, e.g. during draining of oil.

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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.

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2 General description
2.1 General description
Introduction
LF are air-cooled, single-stage, two cylinder piston compressors delivering oil-free air. They are built for
effective working pressure up to 10 bar.
Compressor block with unloading valve
Power Pack

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Power Pack with unloading valve
Base mounted

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Tank- mounted, LF2 up to LF5, horizontal receiver
Tank mounted horizontal receiver

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Tank- mounted, Full-Future unit, 475 l receiver
LF Trolley Petrol/Electric
Reference Description
AF Air filter
AR Air receiver
AV Air outlet valve
CV Check valve
Dm Condensate drain valve
Dp Oil drain plug
FC Filler cap
FN Fan
Gp Air pressure gauge

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Reference Description
M Motor
MDR Air pressure switch
Me Electric motor
Mp Petrol engine
P1 Hourmeter, running time
PD Pulsation damper
RV Pilot valve
S1 On/off switch
S2 On/off switch dryer
SG Oil sight glass
SV Safety valve
UA Unloader
US Blow-off silencer
Y1 Loading solenoid valve
Reference Description
1 Cover
2 Air inlet silencer
3 Crankcase
4 Cooling pipe
5 Left cylinder
6 Right cylinder
7 Pictograph, see Pictographs
8 Electric cabinet
9 Dewpoint indicator
10 Refrigerant dryer
11 Lifting yoke
12 Towing handle
13 Fuel tank
Compressor variants
The compressor block includes:
Crankcase (3) and cylinders (5) and (6)
Air inlet filter (AF) and inlet silencer (2)
Fan (FN)
Air cooler piping
Check valve (CV) or Unloader (UA)
Safety valve (SV)
The Power Pack comprises

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For LF 2 up to LF 3: The compressor block as described above, with flanged-on electric motor (M), check
valve (CV) and safety valve (SV).
For LF 5 up to LF 10: the Compressor Block as described above, with flanged-on electric motor (M) and
solenoid valve (Y1)
The tank-mounted unit comprises:
For LF 2 up to LF 3: The Power pack mounted on a horizontal or vertical air receiver (AR) with air outlet
valve (AV), pressure gauge (Gp), safety valve (SV), air pressure switch with an on/off button (MDR) and
condensate drain valve (Dm).
For LF 5 up to LF 10: The power pack mounted on an air receiver (AR) with air outlet valve (AV),
pressure gauge (Gp), safety valve (SV), and condensate drain valve (Dm). An electric cubicle (8) includes
the motor starter. A separate air pressure switch (MDR) is provided.
The base-mounted unit is a fully operational unit with air pressure switch and on/off switches
mounted on a frame (no air receiver).
LF Trolley units are mobile compressors. They are equipped with either a directly flanged electric motor or a
petrol engine. The compressors have two outlet connections:
A connection for compressed air at working pressure.
A connection for compressed air at reduced pressure via a pressure regulator.
The Full-Feature compressor is a tank-mounted compressor provided with a Refrigerant dryer with DD & PD
filter. They remove moisture from compressed air by cooling the air to near freezing point. This causes water to
condense. The condensate is automatically drained. The air is warmed up before leaving the dryer.
2.2 Operation
The compressors are extendible with the following options. For detailed information consult Atlas Copco.
Silencing hood For 90 / 250 /475 Tank Mounted and Base Mounted Units
Receiver upgrade
Receiver size upgrade
90 to 250 Standard Receiver
Vertical Receiver
upgrade 90 or 250 to 250
Only for 2 and 3hp
475 Receiver
upgrade 90 or 250 to 475
Pneumatic drain Not available for Trolley versions
Interstage drain Not available
Transformer 100VA (for cubicle control voltage 400/3/50) YD only
Motor anti-condensation heaters and
thermistor protection Used with LF 2-10 with 400V/50Hz and 460V/60Hz

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CD adsorption dryer LF 2-3 on 90 and 250 receiver
Heavy duty air inlet filter For PP-BM-TM-FF versions
Oil level switch Not available for LF
Receiver wheel set Wheelset for 90/250 receiver
Power supply cable
(3 m) with red CEE 3-pole plug 16A L = 3 mtr
Auto restart offload valve (solenoid valve to make sure unit will
start after power failure)
Timer drain
(solenoid operated)
Used For DOL 230v/50hz and
400v/50hz Units Invalid Combinations for Any other voltages or frequencies and YD units
2.3 Air flow
LF 2 up to LF 10
Air drawn through air filter (AF) and inlet silencer (1) into cylinders (2 and 3) is compressed, then discharged
through cooler piping (4) and (5) and check valve (CV) / unloader valve (UA) into air receiver (AR).

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Air flow and regulating system with DOL starter

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Air flow and regulating system with Y/D starter

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Air flow and regulating system of trolley