ESAB LPH 120 User manual

LPH 120
Bruksanvisning
Brugsanvisning
Bruksanvisning
Käyttöohjeet
Instruction Manual
Betriebsanweisung
Manuel d’instructions
Gebruiksaanwijzing
Instrucciones de uso
Instruzioni per l’uso
Manual de instruções
Οδηγίες χρήσεως
Instrukcja obsługi
0349 301036 011212 Valid for serial no. 152-xxx-xxxx

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1. DIRECTIVE .............................................................................................................................................. 44
2. SAFETY ................................................................................................................................................... 44
3. INTRODUCTION ...................................................................................................................................... 46
3.1 GENERAL .............................................................................................................................................. 46
3.2 SCOPE OF MANUAL............................................................................................................................. 46
3.3 TECHNICAL DATA ................................................................................................................................ 46
3.4 LPH 120 CUTTING SET PACKAGE...................................................................................................... 46
4. INSTALLATION ....................................................................................................................................... 47
4.1 GENERAL .............................................................................................................................................. 47
4.2 EQUIPMENT REQUIRED...................................................................................................................... 47
4.3 LOCATION............................................................................................................................................. 47
4.4 INSPECTION ......................................................................................................................................... 47
4.5 AIR LINES CONNECTIOINS ................................................................................................................. 47
4.6 PRIMARY ELECTRICAL CONNECTIONS............................................................................................ 47
4.7 SECONDARY CONNECTIONS............................................................................................................. 48
5. OPERATION ............................................................................................................................................ 50
5.1 LPH 120 CONTROLS ............................................................................................................................ 50
6. MAINTENANCE ....................................................................................................................................... 51
6.1 CLEANING ............................................................................................................................................. 51
7. CUTTING WITH PT 25 TORCH............................................................................................................... 51
7.1 PIERCING TECHNIQUE........................................................................................................................ 52
8. FAULT TRACING .................................................................................................................................... 52
8.1 COMMON CUTTING PROBLEMS ........................................................................................................ 52
9. SPARE PARTS ...................................................................................................................................... 133
10. ORDERING OF SPARE PARTS........................................................................................................ 137
11. SCHEMATIC DIAGRAM .................................................................................................................... 138

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1. DIRECTIVE
2. SAFETY
Full responsibility for safety of personnel working on or near system rests on user of ESAB Welding
Equipment.
Wrong operation can lead to abnormal situation, injure operator and damage equipment.
All personnel working with welding equipment must be fully familiar with
- handling of equipment
- location of emergency stops
- functions of equipment
- applicable safety regulations
- cutting
Operator must make sure
- no one stays inside work area while machine starts
- no one is unprotected while arc is being struck
Work area must be
- free of machine parts, tools and other objects that can obstruct operator moving within area
- so arranged, that emergency stop buttons are easily accessible
- free from draughts
Personal safety equipment
- always use proper safety equipment such as goggles, non flammable clothing, protective gloves
- never wear loose clothing, belts, bracelets, rings etc., which may catch on equipment or cause burns
Miscellaneous
- only authorised personnel may operate electrical equipment
- check whether return cables are properly fitted and earthen
- requisite fire fighting equipment should be easily available in specially and clearly marked areas
- lubrication and maintenance of welding equipment must not be proceeded during operation.
DECLARATION OF CONFORMITY
Esab Welding Equipment AB, S-695 81 Laxå, Sweden, gives its unreserved guarantee that
Plasma Arc Cutting Set LPH 120 from serial number 907 complies with standard EN 60974-1, in
accordance with the requirements of directive (73/23/EEC) and addendum (93/68/EEC) and with
standard EN 50192, EN 50199, in accordance with the requirements of directive (89/336/EEC) and
addendum (93/68/EEC).
----------------------------------------------------------------------------------------------------------------------------------
-
Göteborg 99-08-30
Bo Sjöberg
Managing Director
ESAB AB
Box 8004
402 77 Göteborg
Sweden Tel: [phone] Fax: [phone]

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! WARNING !
ARC WELDING AND CUTTING CAN BE INJURIOUS TO YOURSELF AND OTHERS. TAKE
PRECAUTIONS WHEN WELDING OR CUTTING. ASK YOUR EMPLOYER FOR SAFETY PRACTICES
THAT SHOULD BE BASED ON MANUFACTURER’S HAZARD DATA.
ELECTRIC SHOCK - Can kill
- Install and earth welding equipment in accordance with obligatory standards.
- Do not touch live electrical parts or electrodes with bare skin, wet gloves or wet clothes.
- Insulate yourself from earth and workpiece.
- Ensure your work position is safe.
FUMES AND GASES - Can be dangerous to your health
- Keep your head away from fumes.
- Use ventilation and/or extraction to keep fumes and gases away from your breathing zone
and surroundings.
ARC RAYS - Can injure eyes and burn skin
- Protect your eyes and skin. Use correct welding screens, filter lens and wear protective clothes.
- Protect bystanders with suitable screens or curtains.
FIRE HAZARD
- Sparks (spatter) can cause fire. Make therefore sure there are no inflammable materials nearby.
NOISE - Excessive noise can damage your hearing.
- Protect your ears. Use ear defenders or other hearing protection.
- Warn bystanders of the risk.
MALFUNCTION - Call expert assistance in event of malfunction.
READ AND UNDERSTAND THE INSTRUCTION MANUAL BEFORE INSTALLING OR OPERATING UNIT
PROTECT YOURSELF AND OTHERS !

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3. INTRODUCTION
CAUTION!
All warranty undertakings of supplier cease to apply if customer attempts to rectify any faults on
machine during warranty period.
NOTE. Supplier reserves right to make changes within the unit without further notice.
3.1GENERAL
LPH 120 is compact, self-contained plasma cutting system. As shipped, it’s fully assembled and ready to
operate after being installed. The set consists of LPH 120 power source and heavy duty PT 25 torch, and is
capable of severing materials up to 45 mm thick.
! WARNING !
Use only ESAB Plasmarc torches that are appropriated for use with this power source. Use of other
type of torch may cause ELECTRIC SHOCK HAZARD. Do not use any other torch for use with LPH
120.
3.2 SCOPE OF MANUAL
Purpose of this manual is to provide the operator all information necessary to install and operate LPH 120
set. Technical reference materials are enclosed, to help with possible troubleshooting.
3.3 TECHNICAL DATA
Rated 60% Duty Cycle*120A 120A
Output 100% Duty Cycle*60A/90A 60A/90A
Output Current Range 60÷120A 60÷120A
Open Circuit Voltage 310V 310V
Supply cable 4x6 mm24x16/4x6/4x6 mm2
Rated primary input (max) 400-415V
3~50/60Hz
45A/phase
230V/400-415V/440V
3~50/60Hz
78A/45A/41A/phase
Air Requirements
Plasma
Cooling
PT 25
54÷66 l/min 4,9 bar
132÷170 l/min 5,2 bar
54÷66 l/min 4,9 bar
132÷170 l/min 5,2 bar
Max. cutting thickness 45 mm 45 mm
Dimensions Length
Height
Width
760
845
390
760
845
390
Weight of LPH 120 167kg 167kg
(*) Duty cycle is based on a 10-minute period; therefore, a 60 % duty cycle means that the power source
may operate for 6 minutes with a cool down period of 4 minutes.
100 % duty cycle means continuous operation of the power source.
NOTE: machine has enclosure class IP23 which means, that it can be operated indoors and outdoors.
NOTE: symbol S points, that unit may be operated in areas of increased electric shock hazard.
3.4 LPH 120 CUTTING SET PACKAGE
No. Qty. Req.
400-415V
3~ 50/60Hz
Qty. Req.
230V/400-415V/440V
3~ 50/60Hz
Part No. Description
1 1 - 0457 291 880 Plasma arc source LPH 120
2 - 1 0457 291 881 Plasma arc source LPH 120
3 1 1 0457 291 018 Current wire with clamp
4 2 2 0457 290 048 Fuse 1,6A
5 1 1 0457 290 071 Quick detachable coupling
6 1 1 0457 290 072 Hose clip
7 1 1 0349 301 036 Instruction manual LPH 120
8 1 1 0558 000 724 Plasma cutting torch PT 25
9 1 1 0558 000 884 Instruction manual PT 25
10 1 1 0349 302 131 Stand off guide
11 1 1 0349 302 132 Stand off guide

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4. INSTALLATION
4.1GENERAL
Correct installation is very important for trouble-free and satisfactory operation of LPH 120. It is suggested
that each step of this section is carefully studied and followed.
4.2 EQUIPMENT REQUIRED
Source of clean and dry compressed air capable of forcing air flow rate of 300l/min @ 4,8 – 5,2 bar.
Maximum air pressure at unit input should not exceed 7 bars.
4.3 LOCATION
Adequate ventilation is necessary to provide proper cooling of power source. Amount of dirt, dust and
excessive heat, that unit is exposed to, should be minimised. Between LPH 120 and wall (or any obstruction)
should remain distance of at least 300 mm, to secure proper air movement through it.
CAUTION
Installation of any kind of filtering device will reduce volume of through-flowing air, subjecting
therefore interior of machine to overheating. Warranty is void if any type of filter device is employed.
4.4 INSPECTION
A. Remove shipping container and all packing stuff and inspect unit for any sign of damage.
Notify transporters of any defects or damages at once.
B. Check container for any loose parts before disposal.
C. Check air louvers and any other openings to make sure any obstruction is removed.
4.5 AIR LINES CONNECTIOINS
To assembly air lines put on it hose clip and press in quick detachable coupling, that are delivered in
container, and tighten clip next to hose end.
4.6 PRIMARY ELECTRICAL CONNECTIONS
! WARNING !
ELECTRIC SHOCK CAN KILL! Precautionary measurements should be made to provide maximum
protection against electric shock. Disconnect power cable from mains socket before any
connections are made inside power source.
! WARNING !
Operator must make sure, if unit is properly configured for mains voltage.
LPH 120 machines are equipped with 3m, 4-strands power cables for 3-phase mains connection. Switch
board that unit is to be fed from must be equipped with proper line fuses or circuit breakers (see TECHNICAL
DATA). Power cable may be connected directly to wall disconnect switch or be equipped with suitable plug.
! WARNING !
Chassis must be properly connected to ground. Otherwise it may result in electric shock, burns or
death.

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4.7 SECONDARY CONNECTIONS
! WARNING !
Before making any connections make sure unit is disconnected from mains (by unplugging power
cable, opening switchboard switch or opening disconnect switch).
1. Connect air supply line to inlet of regulator.
2. Clamp work cable to workpiece. Make sure the workpiece is connected to ground with properly sized
cable.
Fig. 4-1. LPH 120 connection diagram.

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Fig. 4-2. Ground and current cable connections.

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5. OPERATION
! WARNING !
ELECTRIC SHOCK CAN KILL!
- Do not operate unit with cover removed.
- Do not feed unit while it’s being held or carried.
- Do not touch any part of torch head (nozzle, heat shield and electrode) when unit is turned on.
! WARNING !
ARC RAYS CAN BURN EYES OR SKIN!
NOISE CAN DAMAGE HEARING!
- Wear helmet with No. 6 or 7 lens.
- Wear eye, ear and body protection.
CAUTION
Position machine at least 3 m from cutting zone. Sparks and hot slag can damage it.
5.1LPH 120 CONTROLS
A. POWER SWITCH. Turns the unit on when set to 60A/90A/120A, ‘power’ indicator lights green, fan starts
running.
B. OUPUT CURRENT CONTROL. Stepwise by means of POWER SWITCH.
C. AIR TEST BUTTON (on front panel of the unit) in test position enables setting pressure before cutting is
started.
The following activities shall be done to set the required pressure:
•set air pressure knob 6 to maximum pressure (knob turned maximally to the right )
•when air test button 3 pressed, set the pressure of 5,2 bar by means of pre-regulator on air filter 19
, observing the readings of pressure gouge 7
•when air test button 3 pressed, set the pressure of 4,9 bar by means air pressure knob 6
•block the air pressure knob and air filter pre-regulator before turning
D. FAULT LIGHT. Will glow yellow under following conditions:
FLOW FAULT. Indicates too low air flow rate. (continuous light, only when el-valve opened)
OVER TEMPERATURE. Indicates that duty cycle has been exceeded. (flashing light)
Allow unit to cool down before returning to work.
After fault abates, all signals will automatically reset.
E. ARC-ON LIGHT. When lit red indicates that main contactor is closed, which means torch is
energised (CAUTION! 310V) and source is ready to cut. In case of no indication while torch switch is
depressed immediately turn the machine off and call service.
NOTE: ARC ON light may turn off if within 2 sec since torch switch is depressed cutting process will not be
proceed. It is automatic feature that guarantees safe operation of machine (obligatory for units with S
symbol).
Fig. 5-1. LPH 120 Controls.
No. Description
1
2
3
4
5
6
7
8
9
10
19
power switch knob
“power on” LED
air test button
“arc on” LED
“fault” LED
air pressure knob
pressure gauge
line outlet (rubber)
current cable socket
wheel
air filter-preregulator

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6. MAINTENANCE
NOTE: All warranty undertakings given by supplier cease to apply if customer attempts to rectify any
faults on machine during warranty period.
6.1CLEANING
A. Power source should be regularly blown with dry compressed air at reduced pressure, more frequently in
dirty environment.
B. Occasionally drain water or oil from steam trap.
7. CUTTING WITH PT 25 TORCH
Use the following procedures to cut with the PT 25 torch.
A. Hold the torch nozzle approximately 3 to 5 mm above the work and tilted at about 15-30º. This reduces
the chance of spatter entering the nozzle
B. Depress the torch switch. Air should flow from the torch nozzle.
C. 1,5 seconds after depressing the torch switch (at first start or after 1 min pause), the pilot arc should start.
The main arc should immediately follow , allowing the cut to begin.
D. After starting the cut, the torch should be maintained at a 5-15º forward angle. This angle is especially
useful in helping to create a “drop” cut. When not using the standoff guide, the nozzle should be held
approximately 2.5÷4 mm from the work.
E. When ending a cut, the torch switch should be released and lifted off the workpiece just before the end of
the cut. This is to prevent the high frequency from re-igniting after cutting arc extinguishes and causing
damage to the nozzle (double arcing).
F. For rapid re-starts, such as grate or heavy mesh cutting, do not release the torch switch. In the postflow
mode (i.e. 1 min period, when el-valve remains opened), the arc can restart immediately by depressing
the torch switch. So as to avoid the 1,5-second preflow portion of the cutting cycle, work should be
undertaken within 1 min.
Fig. 7-1. Effect of cutting speed.

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7.1PIERCING TECHNIQUE
Fig.7-2. Piercing technique using PT 25 torch.
8. FAULT TRACING
8.1COMMON CUTTING PROBLEMS
Below are listed common cutting problems, followed by possible cause of each. If problems are caused by
power source, refer to maintenance section of this manual. If it’s still impossible to correct the problem,
contact your ESAB distributor.
A. Insufficient penetration.
1. Too low current.
2. Cutting speed too fast.
3. Damaged cutting nozzle.
4. Improper air pressure.
5. Low air flow rate.
E. Uneven arc.
1. Damaged nozzle or worn electrode.
B. Main arc extinguishes.
1. Cutting speed too slow.
2. Worn electrode
F. Unstable cutting conditions.
1. Incorrect cutting speed.
2. Lose cable or hose connections.
3. Electrode and/or nozzle in poor condition.
C. Dross formation.
(For some material thickness it may be impossible to get dross free
cuts.)
1. Current too low.
2. Cutting speed too fast or too slow.
3. Improper air pressure.
4. Defective nozzle or electrode.
5. Low air flow rate.
G. Main arc does not transfer.
1. Worn electrode.
2. Loose connections.
3. Worn cable.
D. Double arcing.
1. Low air pressure.
2. Damaged cutting nozzle.
3. Loose cutting nozzle.
4. Heavy spatter accumulation on nozzle.
H. Short consumables life.
1. Improper gas pressure.
2. Loose connections.
3. Low air flow rate.