LTN 160/200
Aristotig 160/200
Service manual
0740 800 061
040823
Valid for serial no. 313-xxx-xxxx to 011-xxx-xxxx
LIST OF CONTENTS
Page
READ THIS FIRST . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
COMPONENT DESCRIPTION, LTN 160/200 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
WIRING DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
LTN 160 Valid for ser.no. 313--xxx--xxxx to ser.no. 508--xxx--xxxx . . . . . . . . . . . . . . . . . . . . . .
LTN 160 Valid from ser.no. 540--xxx--xxxx . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
LTN 200 Valid for ser.no. 313--xxx--xxxx to ser.no. 508--xxx--xxxx . . . . . . . . . . . . . . . . . . . . . .
LTN 200 Valid from ser.no. 540--xxx--xxxx . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Transient protection, rectifier unit V03, V04 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
BLOCK DIAGRAM . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CIRCUIT BOARD AP01 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
1 Power supply . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
2 Power supply monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
3 Start / Stop input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
4 Remote control input . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
5 Shunt input with amplifier AP10 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
6 Arc voltage monitoring . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
7 HF generator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
8 Gas valve . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
9 Machine type indicator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
10 Thermal overload cutout . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
11 Welding process control . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Hot start MMA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
12 Control panel interface circuits . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
13 Pulse width modulator . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
14 Gate circuit . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Checking the gate pulses . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Component positions, circuit board AP01 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TRANSISTOR BOARD AP02 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TRANSISTOR BOARD AP03 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
MOS TESTER . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SOFT STARTING . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
CONTROL PANEL AP05 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DISPLAY BOARD AP06 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SUPPRESSION CIRCUIT BOARD AP07 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SUPPRESSION CIRCUIT BOARD AP08 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
LTN 160/200 with ser.no. 313--, 405--, 440--, and 508--xxx--xxxx . . . . . . . . . . . . . . . . . . . . . . .
LTN 160 with ser.no. 540-- and 628--xxx--xxxx . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
LTN 200 with ser.no. 540-- and 628--xxx--xxxx . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SUPPRESSION BOARD AP09 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
FAULT CODES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
DISASSEMBLY / REASSEMBLY . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Rectifier unit (V03, V04) . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Assembling the diode modules . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Removal of transistor circuit boards AP02 and AP03 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Refitting the transistor circuit board . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Fitting the main transformer TC02 . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
LOAD CHARACTERISTICS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
TECHNICAL DATA . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
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INSTRUCTIONS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
INTRODUCTION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
INTSTALLATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
OPERATION . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Control panel . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
MAINTENANCE . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
SPARE PARTS . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
NOTES . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . . .
Rights reserved to alter specifications without notice.
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READ THIS FIRST
Maintenance and repair work should be performed by an experienced person, and electrical
work only by a trained electrician. Use only recommended replacement parts.
This service manual is intended for use by technicians with electrical/electronic training for
help in connection with fault-tracing and repair.
Use the block diagram as a form of index for the description of operation. The circuit board
is divided into numbered blocks, which are described individually in more detail in the
description of operation. All component names in the wiring diagram are listed in the
component description.
This manual contains details of all design changes that have been made up to and including
August 2004.
This manual is valid for LTN 160 and LTN 200 with serial numbers:
313- xxx- xxx, 405-xxx-xxxx, 440-xxx- xxxx, 508- xxx- xxxx, 540- xxx- xxxx,
628- xxx- xxxx, 011-xxx-xxxx
The LTN 160 and LTN 200 are designed and tested in accordance with international
and European standard IEC/EN 60974- and EN 50199.
-1
On completion of service or repair work, it is the responsibility of the person(s) etc.
performing the work to ensure that the product does not depart from the requirements
of the above standard.
WARNING
ARC WELDING AND CUTTING CAN BE INJURIOUS TO YOURSELF AND OTHERS. TAKE PRECAUTIONS WHEN WELDING. ASK FOR YOUR EMPLOYER’S SAFETY PRACTICES WHICH SHOULD BE
BASED ON MANUFACTURERS’ HAZARD DATA.
ELECTRIC SHOCK - Can kill
S
Install and earth the welding unit in accordance with applicable standards.
S
Do not touch live electrical parts or electrodes with bare skin, wet gloves or wet clothing.
S
Insulate yourself from earth and the workpiece.
S
Ensure your working stance is safe.
FUMES AND GASES - Can be dangerous to health
S
Keep your head out of the fumes.
S
Use ventilation, extraction at the arc, or both, to keep fumes and gases from your breathing zone and
the general area.
ARC RAYS - Can injure eyes and burn skin.
S
Protect your eyes and body. Use the correct welding screen and filter lens and wear protective
clothing.
S
Protect bystanders with suitable screens or curtains.
FIRE HAZARD
S
Sparks (spatter) can cause fire. Make sure therefore that there are no inflammable materials nearby.
NOISE - Excessive noise can damage hearing
S
Protect your ears. Use ear defenders or other hearing protection.
S
Warn bystanders of the risk.
MALFUNCTION - Call for expert assistance in the event of malfunction.
READ AND UNDERSTAND THE INSTRUCTION MANUAL BEFORE INSTALLING OR OPERATING.
PROTECT YOURSELF AND OTHERS!
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COMPONENT DESCRIPTION, LTN 160/200
This component description refers to the wiring diagrams.
The LTN 160 and the LTN 200 are primary- switched power units, using parallel- connected
MOSFET-transistors as the switching elements. The switching frequency is 36.5 kHz. The
conducting interval varies between zero and 11 µs, depending on the welding current output.
The conducting time and frequency are controlled by circuit board AP01.
WARNING !
STATIC ELECTRICITY can damage circuit
boards and electronic components.
S
ESD
Observe precautions for handling electrostatic
sensitive devices.
S
Use proper static-proof bags and boxes.
AP01
The main circuit board with control electronics.
See block diagram on page 14 and description on page 16.
AP02
Circuit board with power transistors for the positive pole,
see description on page 28.
WARNING! the transistors are connected to mains voltage potential.
AP03
Circuit board with power transistors for the negative pole,
see description on page 30.
WARNING! the transistors are connected to mains voltage potential.
AP04
Interference suppression circuit board, transient protection, protecting the
secondary diodes against transients.
Replaced by capacitors C10 from serial number 628- xxx- xxxx see:
Transient protection, rectifier unit V03, V04 on page 13.
AP05
Circuit board control panel. The circuit diagram is shown on page 34.
AP06
Display driver board with pulse generator. The circuit diagram is shown on
page 36.
AP07
Interference suppression circuit board: see the circuit diagram on page 37.
AP08
Interference suppression circuit board: see the circuit diagram on page 38.
AP09
Interference suppression circuit board, remote control connector, see the
diagram on page 40.
AP10
Circuit board shunt amplifier, see description on page 19.
AP11
HF generator.
C01
Capacitor, 0.1µF, 1000 VDC, transient protection.
C02
Capacitor, 1000µF, buffer/smoothing capacitor. Time to discharge after
turning off the unit: about two minutes.
C03
See C02. This capacitor is only fitted in LTN 200.
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C04
Decoupling capacitor, 0.1µF, 1000 VDC, protects against HF.
C05
2 - capacitors, 4.7µF, see L02.
-
C06 - C09
-
Capacitor, 0.1µF, 400 VDC
C10
2 - capacitors, 12 nF. Protection against transient voltages.
Replacing AP04 from serial number 628- xxx- xxxx. From serial number
011-xxx-xxxx the capacitors are replaced by L04 and L05 see:
Transient protection, rectifier unit V03, V04 on page 13.
EV01
Fan, 24 VDC
HL01
Lamp, 28 V, white, lights when mains power is on.
L01
Secondary inductor.
L02
Inductor, forms an LC circuit with C05 and V06 to reduce the risk of arc
extinction at low welding currents.
When V03 conducts, the LC circuit charges up. The circuit is capable of
temporarily maintaining a high arc voltage at low current, thus reducing the
risk of arc extinction.
Diode V06 prevents capacitor C05 from going negative.
L03
Primary inductor, improves the machine’s form factor, i.e. reduces the mains
load. Inductor L03 is only mounted in LTN 160.
L04, L05
Ferrite ring cores, transient voltage protection.
Replaces C10 from serial number 011- xxx- xxxx.
-
QF01
Mains power supply switch, 2- pole in the LTN 160 and
3-pole in the LTN 200.
R01
Resistor, 3.9 kΩ 5 W.
RS01
Shunt, 120 mV at 140 A (LTN 160) or 200 A (LTN 200).
ST01
Thermal overload cutout, for overload protection, mounted on the main
transformer (TC02) winding.
LTN 160: breaks at 130 _C and resets at 100 _C.
LTN 200: breaks at 150 _C and resets at 130 _C.
TC01
Control power transformer. The primary is supplied at 230 V (LTN 160) or
400 V (LTN 200), with secondary output voltages of 9, 20, 26 and 42 V.
Machines produced after week 719 have fuses fitted on the control transformer.
TC02
Main transformer. For fitting instructions, see page 45.
TV01
HF transformer.
V01, V02
After replacing the rectifier bridges, the machine must be soft-started: see
instructions on page 33.
Rectifier bridge V02 is only mounted in the LTN 200.
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V03, V04
Rectifier and freewheel diodes.
V03 rectifies the welding current.
During the time interval between two voltage pulses from transformer
TC02, the freewheel diodes V04 maintain the welding current from inductor
L01.
Before serial number 628- xxx- xxxx:
V03 consists of six parallel- connected diodes, and V04 consists of eight
parallel-connected diodes. V03 and V04 are mounted on the same cooling
fins. If any of the diodes is/are faulty, the entire cooling fin unit must be
replaced, as the diodes are soldered to it.
For spare parts see the spare parts list item 430.
From serial number 628- xxx- xxxx:
A new rectifier unit is introduced. On the cooling fins in the LTN 160 is one
diode module mounted and in the LTN 200 are two diode modules mounted.
Each diode module consists of two diodes.
For installation instructions, see page 43.
V05
LED, yellow. Lights when thermal cutout ST01 operates (breaks) as a
result of high temperature.
V06
Diode, see L02.
X01 - X02
-
Terminal block.
XS . .
Sleeve connectors.
XS04
26-pole ribbon cable connector.
XS10
12- pole Burndy contact, for connection of remote control unit.
-
XS11
TIG central connector: only LTN models -880 and -882.
XS12
2-pole Cannon connector, only LTN models - 881, - 883 and - 884.
XS13
Welding current connector, OKC, only LTN models - 881, - 883 and - 884.
XS14
Welding current terminals, (two), OKC type.
XS20
26- pole connector for ribbon cable.
-
YV01
Solenoid valve.
WIRING DIAGRAM
The wiring diagrams for the LTN 160 and 200, on pages 10 and 12 are valid from serial
number 540- xxx- xxxx. For serial no. 628- xxx- xxxx and 011- xxx- xxxx changes are made
to the rectifier unit, which affects the wiring diagrams. The changes in the diagrams are
shown on page 13.
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LTN 160
Valid for ser.no. 313--xxx--xxxx to ser.no. 508--xxx--xxxx
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LTN 160
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Valid from ser.no. 540--xxx--xxxx
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LTN 200
Valid for ser.no. 313--xxx--xxxx to ser.no. 508--xxx--xxxx
AP11
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LTN 200
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Valid from ser.no. 540--xxx--xxxx
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Transient protection, rectifier unit V03, V04
C10
LTN 160
LTN 200
Before serial number 628-xxx-xxxx, circuit board
AP04 protects against transient voltages.
LTN 160/200
with serial number 011-xxx-xxxx.
The two ferrite ring cores L04 and L05
protects against transient voltages.
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LTN 160/200
with serial number 628-xxx-xxxx.
The two capacitors C10 protects against
transient voltages.
BLOCK DIAGRAM
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1
Power supply
2
Power supply monitoring
3
Start / Stop input
4
Remote control input
5
Shunt input with amplifier
6
Arc voltage sensing
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7
8
Gas valve
9
Machine type selection
10
Thermal overload switch
11
Welding process control
12
Interface circuits for control panel
13
Pulse width modulator
14
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HF unit
Gate circuit
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CIRCUIT BOARD AP01
This description refers to the block diagram on page 14 and to the components position
diagram on page 26.
Only those parts connected to the board’s inputs and outputs are described here. If the circuit
board is faulty, it must be replaced.
After replacing the circuit board, the machine must be soft- started. See the instructions
on page 33.
1
Power supply
The power supply to the board can be divided into three parts; a, b and c.
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The supply voltage from transformer TC01 is rectified and voltage regulator VR2
stabilises the supply to +5 ¦0.25V DC.
Resistors R126 and R127, capacitor C104 and diode D27 form a voltage monitoring
circuit for the unregulated supply to voltage regulator VR2.
The voltage from potential divider R126/R127 is connected to pin 9 of IC7: see 2)
below. The voltage is about 2.5V.
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Voltage regulator VR4 supplies the fan EV01 with +28V.
Voltage regulator VR3 produces a stabilised +15V supply, which is used to supply
the remote control unit. This supply is referred to as +15VB, and its neutral point,
0VB, is separated from the electronic neutral (0V). Potentiometer R122 is used to
adjust the voltage. See also 4) on page 18.
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Voltage regulator VR1 produces an output voltage of +20 ¦1.0V, which supplies the
pulse width modulator output stage (Block 13).
Potential divider R100/R101 supplies 2.6V to the processor in Block 11. This
provides a signal that the power supply is available.
The +27V unregulated DC power supply to VR1 also supplies relay RE1 in Block 7
and indicating lamp HL01 via resistor R120.
Zener diode D22 drops the voltage to +15V, and this, together with the -15V supply,
powers the analogue circuits. The processor monitors the - 15V supply by a signal
from resistor R54.
2
Power supply monitoring
IC7 and IC9 monitor the voltage of battery
BA1. The nominal battery voltage is 3V. If
it falls below 2.5V, the display shows error
message E06. Battery life is about five
years.
The machine also operates without battery,
but data stored in the welding data memory,
see page 53, disappears when the mains
voltage is switched off. At power up default
values will be read into the memory.
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A voltage of about 2.5V is supplied to IC7, pin 9, from power supply circuit 1a.
If this voltage drops below the threshold voltage of 1.3V, pin 10 of IC7 goes low,
providing the processor with a low power supply voltage signal. The processor then
” warning signal in the display and stores current data.
generates a ”
If the +5V supply to pin 3 of IC7 drops below 4.65V, pin 15 goes low and inhibits
the pulse width modulator in block 13. The processor receives a reset signal and
data in the RAM memory is protected by the backup battery power supply.
Pin 2 of IC7 supplies the RAM memory in Block 11 with power, both when the
machine is energised and when it is shut down.
When power to the machine is turned off, the display also shows ”
confirm that the processor has stored the current data.
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” to
3
Start / Stop input
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The output signal from IC14, pin 4, goes high (+5V) when the torch contact switch
is not activated, and low (0V) when it is activated.
4
Remote control input
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If the remote control input is activated, but there is no reference signal, resistor R72
holds the reference input low. This results in a welding current of 3A for TIG
welding and 4A for MMA welding.
The remote control unit plug must incorporate a link between pins L and M. When
the remote control unit is connected, the voltage at the cathode of diode D19 is 0V.
With the remote control unit removed, the voltage at the cathode of the diode is +5V.
When adjusting the +15VB voltage, link connections C3 and C4 and measure the
voltage at the cathode of diode D12. The voltage there must be 5.1 ¦0.05V. Adjust
the voltage by means of resistor R122: see circuit diagram 1b on page 16.
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5
Shunt input with amplifier AP10
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Shunt amplifier circuit board AP10 is supplied with ¦15V from circuit board AP01.
At no-load voltage, the circuit board’s neutral voltage (0V) is at the same potential
as the welding circuit negative connection.
In the LTN 160, 120 mV shunt voltage corresponds to 140 A welding current. In the
LTN 200, 120 mV shunt voltage corresponds to 200 A welding current. In order to
be able to use the same programs in both machines, a simple resistor network
interface circuit (see 9) on page 21 tells the processor which type the machine is.
In the 200 machine, the signal from the shunt is amplified by the shunt amplifier, so
that a 120 mV input signal from the shunt produces a 6.66 V output signal. Resistors
R10, R6 and R7 on circuit board AP01 divide this voltage to 2.12 V, which is then
supplied to pin 3 of IC2.
In the 160 machine, transistor Q1 is turned on by IC8. This connects resistor R9 to
0V, connecting resistors R8 and R9 in parallel with R6 and R7. With R10, these
resistors form a potential divider which divides the 6.66 V to 1.48 V, which is then
supplied to pin 3 of IC2.
IC2 is a buffer circuit. The processor receives a signal representing the welding
current from output pin 6 of IC2 via filter R20 and C17. Resistor R4 connects the
shunt signal to the control amplifier.
The LTN 160/200 has different current setting resolutions in the TIG and MMA
modes. In the TIG mode, the welding current can be set in 1A steps, while in the
MMA mode, the current can be set in 2A steps. This means that the lowest current
in the MMA mode is 4A, while in the TIG mode it is 3A.
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Component positions, AP10
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- 19 -
6
Arc voltage monitoring
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This circuit measures and scales the arc voltage to a suitable level for the processor.
64V arc voltage produces a voltage signal of 5.1V at the cathode of diode D3.
Open-circuit voltage control
The arc voltage is connected to input D2 and supplied to potential divider R29 and
R30, the output from which is supplied to the voltage control circuit. The
open-circuit voltage must be about 70V.
7
HF generator
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WARNING: Dangerous voltages in this circuit.
When the welding torch switch is operated, and the open- circuit arc voltage is over
50V, relay RE1 closes and turns on HF generator AP11. It remains activated for
0.75 seconds. If the arc has not struck within this time, the relay drops off.
The voltage on the primary side of HF transformer TV01 is about 400 V, and the
secondary voltage is about 8 kV.
a.
Filter RC1 is not fitted to machines with serial numbers of 313- 351- xxxx and
above. Where the filter is fitted (i.e. to earlier machines), it can happen that the
welding torch produces weak HF sparks even when the torch trigger switch
contact is not activated. This is not dangerous to the operator, but the filter
should be removed when the machine is next being serviced.
From serial number xxx- 006- xxxx a new type of HF generator is used,
0367 268 001. This generator produces about 500 V on the primary side of the HF
transformer and about 10 kV on the secondary side.
The new HF generator replaces the old type as spare part for older machines. The
colour of the new type is grey, the old is black. The new has screw connections for
the connection cables and different hole pattern for the mounting.
When fitting the new generator to older machines: three new mounting holes for the
generator must be drilled and the cable shoes must be removed from the connection
cables. Fit the generator with the connection terminal turned towards the base plate.
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- 20 -
8
Gas valve
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Operating the torch trigger switch causes semiconductor relay RE2 to conduct and
energise solenoid valve YV01. C82 and R111 form an HF filter.
9
Machine type indicator
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As the same circuit boards are used in the Aristotig 160 and 200, it is necessary for
the processor to know what type of machine it is controlling. A link is therefore
provided connector G to short out pull- up resistors R113 and R114. When it
connects G1 - G4, it indicates that the machine is an LTN 160, while when it
connects G1 - G3 it indicates that the machine is an LTN 200.
The relevant input line to the processor (G3 or G4) goes low to indicate which type
the machine is.
10
Thermal overload cutout
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The thermal overload switch, ST01, is normally closed, which means that input K2
is at 10V. This voltage is dropped by the potential divider formed by resistors R31
and R32 to 4.8V, and used as an input voltage to the processor.
LED V05 indicates excessive temperature. When the thermal overload cutout
operates, the LED lights up.
If you connect a water cooler with water flow switch to the LTN 200, remove
connector XP01 and connect the flow switch to XS25.
The connectors XP01 and XS25 are not fitted to the LTN 160.
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- 21 -
11
Welding process control
The processor inputs are the set values of welding data and the arc voltage. The
processor also calculates a set value signal for welding current and supplies this to
the current control amplifier.
The process regulator control principle
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Hot start MMA
In the MMA normal welding mode, the welding current is briefly elevated at the
start of welding. The higher current setting is engaged for 150 milliseconds.
The starting current is twice the normal welding current (i.e. twice the set value),
subject to a maximum of 210 A for the LTN 160 and 300 A for the LTN 200.
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Welding start, normal welding, MMA
1. Contact between the electrode and the workpiece.
2. Starting current for 150 ms.
In the MMA drop welding mode, the starting current is three times the set value, but
the duration is shorter at only 50 ms. The maximum starting currents are the same as
for normal welding.
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Welding start, drop welding, MMA
1. Contact between the electrode and workpiece.
2. Starting current for 50 ms.
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- 22 -
12
Control panel interface circuits
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All machine functions are controlled from the panel on the front of the machine.
The display window and the LEDs are driven by IC21 and connected by a ribbon
cable to board contact B, pins 3-18.
The pulse generator on the front panel is supplied at +5 V via inputs B25 and B26.
Pulses are supplied from the pulse generator to connections B23 and B24 with a 90_
mutual phase displacement. The pulse generator does only supply pulses when it’s
shaft is turned. Resistors R97 and R98 are pull- up resistors. IC11 squares up the
pulse flanks.
The two red
and the two green
pushbuttons are connected to 0 V.
Pressing any of them pulls down the corresponding input (B19 - B22) to 0 V, and
the signal is filtered by an RC filter network formed by capacitors C72 - C75 and
resistors R93 - R96 before being applied to the processor.
-
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- 23 -
13
Pulse width modulator
The pulse width modulator determines
the frequency and pulse time of the
MOSFET transistors’ control pulses.
It is important that the frequency and
maximum pulse time are within the
specified tolerances. See the
instructions on next page.
IC5 controls the pulse frequency, the
pulse time and inhibition of pulses.
Transistor Q12 supplies the pulse transformer’s primary winding. Diodes D17 and
D18 are squelch diodes that protect Q12 against back- emf from the transformer.
-
14
clt
Gate circuit
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The MOSFET transistors’ drive stage produces control pulses for the gate- source on
the power transistors. There is a separate output for each switch unit.
All gate circuits are galvanically isolated from other circuits on the board. The
insulation voltage between the pulse width modulator and the gate circuits is 4 kV.
WARNING! The gate circuits are at mains voltage.
The two gate circuits are identical, and so only one is described here.
When Q12 conducts, a voltage pulse is produced on the transformer’s secondary
winding. This pulse is conducted via D13, D14 and output E1 to the gate on the
MOSFET transistors. The pulse returns via the source, connection E2, D16 and
C36. The peak gate - source voltage is 14 V.
The gate pulse between E1 and E2 charges C36 to 3.3 V. When Q12 turns off, the
voltage from the secondary of the pulse transformer changes polarity, causing Q14
and Q13 to start to conduct. The gate voltage becomes - 3.3 V, turning off the
MOSFET transistors.
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- 24 -
Checking the gate pulses
If circuit board AP02 or AP03 has failed, the gate pulses must always be checked.
Remove connections XS06 and XS07 (gate pulses). Connect a dummy gate load to
outputs E1 and E2 and to F1 and F2.
Dummy gate load
A set of different gate loads can be ordered from ESAB.
The part number is 0468 469 003. The gate loads can be used to the following
machines: LUC, LHL 130/160, LHL 250/315, LTL 160, LTL315, LUB 315,
LHN, LTN, LTR, LTO, MechTig 315 and Protig 315.
IMPORTANT: never check the gate pulses when AP02 and AP03 are
connected: use a dummy gate load.
The gate pulse minimum level must be - 2 to - 4V, and the average maximum level
13.5 to 16V. Frequency must be 36.5 kHz ±0.5 kHz. Check that the maximum pulse
time, measured at a voltage level of +5V, is 41% ±1.5% of the cycle time.
IMPORTANT: The frequency and pulse time are very important parameters.
If they are incorrect, they can result in transistor failure in the main circuit.
If the gate pulse does not lie within these tolerances, replace circuit board AP01.
After replacing AP01, check the gate pulses again and soft- start the machine, as
described on page 33.
cmha2p25
Gate pulses as measured across a dummy gate load on circuit board AP01
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- 25 -
Component positions, circuit board AP01
1
1
1
WARNING:
High voltage within
the shaded area.
1
1
1
Terminals X1 to X6 are tied to
0 V on the circuit board, and
must have good electrical contact with the screen enclosure.
1
26
1
1
1
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- 26 -
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- 27 -
TRANSISTOR BOARD AP02
Simpified circuit diagram for transistor board AP02 (positive)
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The -880 variant is used in the LTN 160 and the - 882 variant is used in the LTN 200..
Individual transistors must not be replaced: if the circuit board is faulty, it must be replaced
in its entirety. In addition, circuit board AP03 must also be replaced.
Instructions for removing and fitting the circuit board are to be found on page 44.
A01, A02
Connections A01 - A02 are for the gate pulses from circuit board AP01.
D1 - D3
-
Transient voltage protection.
D5
Back- emf protection diode (squelch diode), for main transformer TC02
when the transistors turn off.
F1
Fuse, for protection of circuit board AP01 if circuit board AP02 fails.
Q1 - Q8
-
MOSFET transistors. These require a special instrument.
See MOS TESTER on page 32 for testing.
Due to a change to transistors with higher current rating, the circuit board
may have one transistor less than specified in the diagram above.
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- 28 -
Component positions, circuit board AP02
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- 29 -
TRANSISTOR BOARD AP03
Simpified circuit diagram for transistor board AP03 (negative)
cmha2e08
The -880 variant is used in the LTN 160 and the - 882 variant is used in the LTN 200..
Individual transistors must not be replaced: if the circuit board is faulty, it must be replaced
in its entirety. In addition, circuit board AP02 must also be replaced.
See page 44 for instructions for removing and fitting the circuit board.
A01, A02
Connections A01 - A02 are for the gate pulses from circuit board AP01.
B01, B02
When the machine is loaded, pulses from a trigger pulse winding on main
transformer TC02 are supplied to connections B01 and B02, for use as gate
pulses in controlling thyristor TY1.
D1 - D3
-
Transient voltage protection.
D5
Back- emf protection diode (squelch diode), for main transformer TC02
when the transistors turn off.
Q1 - Q8
-
MOSFET transistors. These require a special instrument.
See MOS TESTER on page 32 for testing.
Due to a change to transistors with higher current rating, the circuit board
may have one transistor less than specified in the diagram above.
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- 30 -
R21
Charging resistor, 12Ω, 10W, for buffer capacitor C02 (C03).
When energising the power unit, pulses from control circuit board AP01
are delayed by 300 ms to allow the buffer capacitor to charge.
R26
Discharge resistor for buffer capacitor C03. This capacitor is only fitted in
LTN 200. After turning off the mains power supply, the discharge time for
the capacitor is about two minutes.
R27
Discharge resistor for buffer capacitor C02. After turning off the mains
power supply, the discharge time for the capacitor is about two minutes.
TY1
Thyristor for shunting charging resistor R21 when the machine is loaded.
If TY1 did not conduct, resistor R21 would burn out when the unit is on
load.
Component positions, circuit board AP03
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- 31 -
MOS TESTER
The MOS tester is a special instrument, and can be ordered only from ESAB’s service
department in Laxå. Order number is 0468 469 001.
Connect the instrument as follows:
S
S
S
S
S
S
Disconnect the power unit from the mains.
Disconnect capacitor C02 (and C03 in LTN 200).
Remove the gate connections from AP01.
Connect the clip on the red wire of the instrument to the red wire (the gate wire) on the
transistor board.
Connect the clip on the yellow wire of the instrument to the yellow wire (the source) on
the transistor board.
Connect the black wire to the cooling fins (drain).
Testing:
S
S
S
S
Press the pushbutton marked TEST.
If the board is healthy, both the red and green LEDs should flash alternately, about once
a second.
If the transistor board is short- circuited, the red LED will light continuously. (Note that
the green LED may also flash, or be continuously lit.)
If the transistor board is open- circuited, the green LED will be continuously lit. Check
that there is good electrical contact between the clip of the black wire and the cooling
fins.
IMPORTANT
Even if only one transistor board is indicated as faulty, both boards must be replaced.
Check the gate pulses from AP01 before commissioning the new transistor boards.
See instruction on page 25.
After replacement of the boards, the machine must be soft-started.
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- 32 -
SOFT STARTING
S
S
S
S
S
S
S
Remove and insulate wires 07 and 08 from rectifier bridge V01: see the circuit diagram
on page 9.
In the LTN 200, also remove and insulate wire 09 to rectifier bridge V02: see the circuit
diagram on page 11.
Connect an external power supply, having a current limit of 1 A, to the positive and
negative connections on V01.
Adjust the power supply voltage to 30 V.
Power the remaining parts of the unit from the normal power supply.
Select MMA mode.
Measure the output voltage from the machine. On the LTN 160 this must be 10V ¦1V,
and on the LTN 200 it must be 6V ¦1V.
Measure the primary voltage to transformer TC02. With a voltage of 30 V across the
buffer capacitor, the waveform must appear as shown below.
Primary voltage at TC02 for 30 V across the buffer capacitor
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- 33 -
cmha2p24
CONTROL PANEL AP05
AP06
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Circuit diagram, control panel AP05
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- 34 -
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Component positions on control panel AP05
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- 35 -
DISPLAY BOARD AP06
AP05
AP07
Circuit diagram, display board AP06
The pulse generator Sw0 is transmitting pulses only when it’s shaft is turned.
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- 36 -
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Component positions on display board AP06
SUPPRESSION CIRCUIT BOARD AP07
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Kretsschema och komponentplacering, avstörningskort AP07
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- 37 -
SUPPRESSION CIRCUIT BOARD AP08
Prevents mains-borne interference to/from the machine.
LTN 160/200 with ser.no. 313--, 405--, 440--, and 508--xxx--xxxx
cny1ae06
Circuit diagram and component positions, circuit board AP08, the board is fitted in LTN 160
and LTN 200 with serial number 313-xxx- xxxx to 508- xxx- xxxx
- -
LTN 160 with ser.no. 540-- and 628--xxx--xxxx
Circuit diagram and component positions, circuit board AP08, the board is fitted in LTN 160
with serial number 540- xxx- xxxx and 628- xxx- xxxx
- - -
LTN 200 with ser.no. 540-- and 628--xxx--xxxx
Most of the machines produced before October 1998 are deliverd with circuit board 0486 356
880. As spare part for those machines circuit board 0486 356 880 or 0486 577 880 may be
used. The new circuit board suppresses noise better than the old board. To fit the new board
in older machines a new mounting hole must be drilled in the mounting plate.
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- 38 -
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cltn0e34
Diagram and component positions for circuit board AP08 with ordering no. 0486 356 880.
The board is mounted in the LTN 200 from serial number 540- xxx- xxxx
- -
Diagram and component positions for the new version of circuit board AP08 (0486 577 880).
The board is mounted in the LTN 200 from October 1998
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- 39 -
SUPPRESSION BOARD AP09
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Diagram and component positions for circuit board AP09
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- 40 -
FAULT CODES
If the integral fault monitoring system detects a fault, the display shows Exx, where xx is a
two-digit number identifying the fault.
Faults E01 - E06 can be detected during the automatic self- test routine that is run when the
unit is switched on. Other faults can be detected as and when they occur.
E01
Memory error in internal RAM (in the processor).
If this code occurs, turn the machine off and then on again. If it persists, replace
circuit board AP01.
E02
Memory error in external RAM (outside the processor).
If this code occurs, turn the machine off and then on again.
If it persists, replace circuit board AP01.
E03
Memory error, program memory (EPROM).
If this code occurs, turn the machine off and then on again. If it persists,
replace circuit board AP01.
E04
Memory error, RAM memory contents test.
Check that the battery voltage is at least 2.5V. If it less than this, replace the battery.
If the voltage is correct, turn the machine off and then on again: if the fault persists,
replace circuit board AP01.
E05
Memory error, variable values outside limits in battery- backed RAM.
Perform the same checks as for error code E04.
E06
Battery voltage below 2.5V. Measure the battery voltage: if it is less than 2.5V,
replace the battery. If the battery voltage is over 2.5V, replace circuit board AP01.
This error code can be reset by pressing one of the arrow pushbuttons. This will
have no effect other than to clear the error code. The display will return next time
the machine is turned on, and can again be cleared by pressing one of the arrow
pushbuttons.
If the battery is not replaced before its voltage has fallen below 2.0V, error code E04
or E05 will be displayed. These error codes cannot be cleared.
E10
Incorrect power supply voltage (should be 20V), tolerance ¦1V.
Use a voltmeter to verify this fault. Measure the voltage from transformer TC01.
If the transformer output voltage is correct, but the 20V supply voltage is wrong,
replace circuit board AP01.
E11
Incorrect power supply voltage (should be - 15V), tolerance +2/- 1V.
Use a voltmeter to verify this fault. Measure the voltage from transformer TC01.
If the transformer output voltage is correct, but the - 15V supply voltage is wrong,
replace circuit board AP01.
E13
High temperature. The thermal cutout has operated and indicating lamp V05 lights.
The machine has been overloaded. Check that the cooling fan is running, and that
the air filter is not blocked.
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- 41 -
E14
Current servo fault: excessive difference between the actual value and the set value
of welding current. The power electronics circuitry is not capable of maintaining
the welding current that the process regulator is demanding.
Tolerances: ¦5A in TIG mode and ¦10A in MMA mode.
This code may occur when welding with electrodes which needs a higher voltage
than the machine can produce. It can also occur if the arc length is too long.
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The process regulator control principle
The process regulator servo compares the actual value signal and the set value
signal, as shown above. The set value signal is the current control signal from the
process regulator. The actual value signal is provided by the shunt signal, supplied
to the processor analogue inputs. These two signals are put through low- pass filters,
each with the same time constant, and are then compared with each other.
The time constant is about two seconds.
This fault code is reset when the welding current returns to within the tolerance
values, when welding is restarted or when the machine is turned off.
It is also possible to reset the display by pressing any of the pushbuttons. Doing this
has no effect other than to reset the display.
This fault code can sometimes occur during abnormal welding conditions, e.g. as a
result of a failed start.
When starting and finishing welding, the current is briefly outside the tolerance
limits. However, the above- mentioned filtering prevents these brief excursions
from triggering the fault code display.
Too low a power supply voltage to the + 5V voltage regulator. The display briefly
shows this symbol when the machine is turned off. If the voltage drops below the
permissible value when the machine is in use, the display will show this symbol
briefly and the machine will then stop.
See also Power supply monitoring on page 17.
The display shows this symbol if the machine’s program has crashed. This can be
caused, for example, by extreme external interference.
If this error code occurs, find and rectify the source of the interference, turn off the
machine, wait five seconds, and start it again.
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- 42 -
DISASSEMBLY / REASSEMBLY
Rectifier unit (V03, V04)
The rectifier unit is mounted in machines with serial number 313- to 540- xxx- xxxx. From
serial number 628-xxx-xxxx it is replaced by the diode modules below.
Removing the rectifier unit
1.
Note which wires are connected to
the respective terminals (d).
2.
Remove the screws (d).
3.
Pull out the rectifier unit.
Refitting the rectifier unit
1.
Press the insulation (f) against
transformer TC02, and slide the
rectifier unit in on the guides (e).
2.
Reconnect the wires to screws (d).
cmha2p28
Rectifier unit V03, V04
Assembling the diode modules
Valid from serial number 628- xxx- xxxx.
1.
Clean the contact surface of the heat sink with
extremely fine abrasive paper.
2.
Apply a thin film of contact oil (see item 454
and 555 in the spare parts list) to the contact
surfaces.
3.
Fit the diode modules and tighten the screws A
(M6) to a torque of 6 Nm. Tighten the screws
B (M4) to a torque of 1 Nm.
The screws C (1/4” 20UNC2B) are to be
tightened to a torque of 6 Nm.
Heat sink with diode module
The picture above is valid for the LTN 160, which has one diode module. Assemble the two
diode modules in the LTN 200 in a similar way.
From serial number 011- xxx- xxxx the diode modules are different connected compared to
the picture above: see the spare parts list. The fitting procedure for the modules is however
the same as described above.
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- 43 -
Removal of transistor circuit boards AP02 and AP03
1.
Remove all wires and busbars connected to the board.
2.
Remove the springs that hold the board (2) in position by prising them off with a
screwdriver (1) between the cooling flange and the spring.
Removal/refitting of transistor circuit board
Refitting the transistor circuit board
1.
When replacing the transistor circuit board, both boards must always be replaced and
new springs must be fitted.
2.
Clean the contact surface (3) of the heat sink with extremely fine abrasive paper.
3.
Apply a thin film of contact oil (see item 454 and 555 in the spare parts list) to the
contact surfaces.
4.
Place the circuit board (2) on the cooling fins. Secure first one spring on each side of the
board by pressing the spring down with a screwdriver (4). Then secure the remaining
springs.
NOTE: The springs must be fitted where there are components that are to be in contact
with the heath sink. Due to a change to transistors with higher current rating, there might
be less transistors on the spare part board than on the original board.
5.
When fitting cable lugs and busbars to the boards, it is important that the washers are
fitted in the correct order. Start by placing the lug on the foil, and then fit a flat washer, a
spring washer and finally the screw.
Connections to circuit board AP03
a LTN 160: not connected
LTN 200: wire 045 to the connection
between C02 and C03
b LTN 160: busbar to positive on C02
LTN 200: busbar to positve on C03
c Busbar connected to negative on C02
d LTN 160: wire 024 from inductor L03
LTN 200: wire 013 from negative of V02
e Gate connection from circuit board AP01
f Connector XS17 from transformer TC02
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- 44 -
Fitting the main transformer TC02
When replacing the main transformer, it is also necessary to replace the transformer core.
This is because the core is bonded with adhesive, and cannot be disassembled.
Adhesive and tape are required when fitting a new transformer, in addition to the coil and
core. Part numbers for the requisite adhesive and tape are shown as Item 428 in the spare
parts list.
1.
Transfer wire 020 and connector XS17 to the new transformer. If the wire needs to be
replaced, it is important to use the correct type of insulation (Teflon)
cmha2p32
Fitting wire 020
2.
Apply a layer of tape (t) to each of the three airgaps in the transformer core. Use the tape
specified in the spare parts list.
3.
Apply Loctite 648 (see the spare parts list) to the contact faces between the cores and
between the core and coil. Secure the transformer in position in the machine. The
adhesive takes about 20 minutes to harden.
Airgap (t) in the transformer core
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cmha2p33
- 45 -
LOAD CHARACTERISTICS
LTN 160
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LTN 200
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- 46 -
TECHNICAL DATA
LTN 160
LTN 200
Load capacity at:
35 % duty cycle, TIG
35 % duty cycle, MMA
60 % duty cycle
100 % duty cycle
160 A / 16 V
140 A / 26 V
110 A / 24 V
80 A / 23 V
200 A / 18 V
200 A / 28 V
150 A / 26 V
115 A / 25 V
Operating range, TIG
Operating range, MMA
3 -- 160 A
4 -- 140 A
3 -- 200 A
4 -- 200 A
Slope up
Slope down
0 -- 10 sec.
0 -- 10 sec.
0 -- 10 sec.
0 -- 10 sec.
Gas pre-flow
Gas post-flow
Pulse time
0 -- 25 sec.
0 -- 25 sec.
0.02 -- 5.0 sec.
(0.001 -- 5.0 sec.)
0.02 -- 5.0 sec.
(0.001 -- 5.0 sec.)
0 -- 25 sec.
0 -- 25 sec.
0.02 -- 5.0 sec.
(0,001 -- 5,0 sec.)
0.02 -- 5.0 sec.
(0.001 -- 5.0 sec.)
Open-circuit voltage
70 V
70 V
Open-circuit power
Active power, at max current MMA
Apparent power, at max current MMA
30 W
4.8 kW
6.9 kVA
50 W
7.2 kW
11.7 kVA
Power factor, at max current MMA
Efficiency, at max current MMA
0.69
0.75
0.63
0.78
Mains connection
Mains frequency
Mains fuse, slow
Mains cable, cross sectional area
230 V ±10%
50 -- 60 Hz
16 A see * below
3x2.5 mm2
3~ 400 V ±10%
50 -- 60 Hz
10 A
4x1.5 mm2
Dimensions l x w x h
Weight
515x285x415 mm
23 kg
515x285x415 mm
23 kg
Application class
Enclosure class
IP 23
IP 23
Pause time
The LTN 160 and LTN 200 complies with the requirements set out in IEC 974--1
The duty cycle refers to the time in per cent of a ten-minute period that you can weld at a
certain load without overloading the welding power source.
The IP code indicates the enclosure class, i. e. the degree of protection against penetration by
solid objects or water. Equipment marked IP 23 is designed for indoor and outdoor use.
The symbol
indicates that the power source is designed for use in areas where there is an
increased electrical hazard.
* To make full use of the LTN 160, it must be protected by a 16 A slow- blow fuse. For
welding up to about 100 A, a 10 A slow- blow fuse will suffice.
-
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- 47 -
INSTRUCTIONS
This chapter is an extract from the instruction manual for the LTN 160 and LTN 200.
INTRODUCTION
Note: This product is solely intended for arc welding.
The LTN 160 and 200 are is equipped with ARC PLUS, a type of control that with MMA
welding provides a more intensive, more concentrated and smoother arc. It reacts quicker
after a short circuiting drop transfer, which reduces the risk of the electrode sticking.
In addition, the machine is equipped with Arc Force, which means that the power source’s
dynamics can be adjusted, softer or harder depending on the type of electrode and the
welder’s preference.
ARC PLUS - because of the regulator’s good characteristics it is only necessary to change
the Arc Force settings in exceptional circumstances.
When drop welding using stainless steel electrodes a special feature on the machine can be
activated to facilitate welding.
LTN 160/200 are available in two designs, one with a central connector and one with an OKC
connector for a TIG torch. The machine is supplied complete with a 5 metre mains cable, 5
metre return cable, gas hose and hose clips. Machines with a central connector are also fitted
with a safety bar to protect the connectors from impact.
As an accessory there is a loop handle to fit on the machines which acts as a cable reel as well
protecting the control panel. There are also two carriages available for transportation with a
gas cylinder and cooling unit.
INTSTALLATION
WARNING
This product is intended for industrial use. In a domestic environment it may cause
radio interference. It is the user’s responsibility to take adequate precautions.
LTN 160 and 200 are equipped with mains voltage compensation, which means that a ¦10%
variation in the mains voltage only results in a ¦0.2% variation in the welding current.
1.
Place the equipment in a suitable place and make sure the machine is not covered or
set- so that cooling is prevented.
-up
2.
Make sure the machine is connected to the correct mains voltage.
Earth according to applicable directives.
3.
Connect the shielding gas.
4.
Connect the TIG torch and the return cable or the MMA welding cables.
The machine is now ready for welding.
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OPERATION
4
5
3 2
8
1
9
10
11 12
7
6
1. Mains power switch
9. Gas nipple (connection of gas cylinder)
2. Yellow LED, indicating overtemperature
10. Connection for TIG torch
3. White indicating lamp
12. Connection for return cable when TIG
welding
ldi
4. Display
5. Setting knob
6. Push- buttons
7. Remote control connection
The welding cable and return cable should
be
b connected to 11 and 12 when welding with
d
d
h
ldi
ih
coated electrodes
8. Dust filter
When the main power switch is switched on the white indicating lamp, on the front, is lit.
To take your mind off the risk of overloading the machine it has been equipped with an
integrated thermostat that trips if the temperature becomes too high.
When this occurs the welding current is cut out and the yellow indicating lamp comes on. In
addition, the error code ”E13” is displayed. When the temperature has dropped the thermostat
automatically resets.
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- 49 -
Control panel
On the front of the machine there is a control panel for the selection of functions and setting
of parameters. This consists of a display, setting knob, LEDs and push- buttons.
By using the push- buttons you can move between the different functions. The selected
function is indicated by respective LEDs coming on.
One line at a time is set. The current line is indicated by a red LED. Movement between lines
takes place using the red arrow keys.
Movement within each line takes place using the green arrow keys.
All settings are made using the setting knob. The LEDs to the right of the display indicate the
actual unit (ampere/volt/seconds). On the lines where only a function is selected, ”
- ” is
shown on the display.
Description of the functions
S
S
Line 1
Line 2
S
Line 3
S
Line 4
S
Line 5
S
S
Line 6
Line 7
bt07d002
Line 1
TIG-welding or MMA-welding
If you select MMA, set the current here and then ignore Lines 2 - 5.
If you select TIG, pass on to Line 2.
MMA Arc Force
When the current is being set, you can also set the required Arc Force. This
varies the dynamic response of the machine, to produce a softer or harder arc.
To activate the Arc Force setting mode, press the two red
arrows
simultaneously for two seconds.
The display shows a value between 0 and 100. Higher values give a harder arc.
The standard Arc Force setting is 10.
Press any of the buttons to return the power unit to the Normal mode.
Set values of Arc Force remain in memory. Different settings can be stored in
the machine’s two welding data memories.
MMA Drop welding (Controlled heat input)
Drop welding can be used when welding with stainless steel electrodes.
This means that the arc is alternately struck and extinguished, in order to
provide better control of the heat input. The electrode need be lifted only
slightly from the workpiece to extinguish it.
cltn0de4
- 50 -
The machine must be in the current setting mode in order to be able to activate
this function. To do so, press the two green
arrows at the same time for
two seconds. The ” - _ - ” symbol indicates that the function has been
activated. Note that the symbol is displayed only briefly.
The drop welding mode remains stored in memory when the machine is
switched off. To reset the machine to the normal welding mode, press the two
green arrows. The display responds by showing the ” _ _ _ ” symbol briefly.
WARNING If the machine is in the drop welding mode when using ordinary
electrodes, the electrodes can easily weld themselves to the workpiece. The arc
will also appear to be pulsing.
Line 2
TIG/HF ignition or TIG/Liftarc ignition
If HF ignition has been selected, the HF generator will be activated when the
torch trigger switch is operated. The HF generator is activated for 0.75 seconds:
if the arc has not struck during this time, the machine turns off the HF generator.
Operate the LIFTARC ignition feature as shown below.
Place the electrode against the workpiece .
Press the torch switch
Tilt the torch a little, lift and an arc is produced
To stop - release the torch trigger
-
Line 3
cltn0de4
Continuous or pulsed current
O O-
- 51 -
O
bt07t001
bt07t002
Line 4
2- stroke or 4- stroke
2- stroke control means that the arc is struck when the torch switch is pressed
and extinguished when it is released.
The diagram to the right shows the control sequence
for 4- stroke welding.
1. First depression of the torch switch starts
the machine on pilot current.
bt07d003
2. When the switch is released, the current increases to the set value.
3. Pressing the switch again reduces the current to pilot current.
4. Releasing the switch extinguishes the arc.
Line 5
Parameter setting
1. Gas pre flow
2. Slope up
3. Pulse current or continuous current
4. Pulse time
5. Pause current
6. Pause time
7. Slope down
8. Gas post flow
LTN 160
0--25 s
0--10 s
3--160 A
0.02--5.0 s
(0.001--5.0 s)
3--160 A
0.02--5.0 s
(0.001--5.0 s)
0--10 s
0--25 s
LTN 200
0--25 s
0--10 s
3--200 A
0.02--5.0 s
(0.001--5.0 s)
3--200 A
0.02--5.0 s
(0.001--5.0 s)
0--10 s
0--25 s
bt07d004
Pulse time/Pause time
The setting range for these parameters is normally 0.02 - 5.0 seconds.
However, by pressing the two green
arrows together for two seconds,
times down to 0.001 second can be set. This extended setting range remains
available until the two green arrows are again pressed. When activating or
de- activating this feature, the machine must be in the pulse or pause time setting
mode.
Times shorter than 0.25 seconds are displayed without a decimal point.
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- 52 -
Line 6
Using the display for parameter measurement
The display can be made to show arc voltage or current while welding is in
progress.
The current value displayed is a mean value of the process regulator signal to the
summing point. The voltage is a mean value of the measured arc voltage.
Voltages are displayed with a resolution of 0.25 V, while currents are displayed
with a resolution of 2 A in MMA mode and 1 A in TIG mode.
The display has a sample- and- hold characteristic, i.e. the value last being
displayed before slope-down continues to be displayed when welding stops.
Line 7
Welding data memory O O 1 O 2 O1- O
-2
A
Four different sets of welding data parameters can be stored in the machine’s
memory: two for TIG welding and two for MMA welding.
The following parameters can be stored:
MMA: Welding current, Arc Force, drop welding/normal welding.
TIG: The alternative selected on Line 3 (Continuous or pulsed current).
All settings on Line 5.
Change welding data memory with the green
arrow pushbuttons.
In the TIG control mode, the data memory can also be changed by briefly
pressing the torch contact, irrespective of whether welding is in progress or not.
Press the two green
arrows together to activate the program switch
mode.
The O 1- indicating lamp is lit when the program switch mode is activated.
-2
If four- stroke control mode has been selected, a brief depression of the torch
switch will change welding data memory. The same applies for two- stroke
control mode if welding is not in progress.
When welding with two-stroke control, welding data memory can be changed
by briefly releasing the welding torch contact.
The welding data memory is battery- backed, so that data is retained even if the
machine is turned off or disconnected from the mains.
Remote control unit
TIG and MMA welding current can be remotely controlled via the remote control input.
If pulsed current is selected in the TIG mode, it is the pulsed current that is remotely
controlled. Stepping the machine forward to the position for setting welding current without
the remote control unit causes the display to show the value that has been set on the remote
control unit.
The remote control unit is activated automatically when the plug is inserted into the contact,
A LED.
with indication of this being provided by the O
Note that pins L and M in the remote control unit plug must be strapped for the automatic
engagement feature to work.
The following remote control units can be connected: PHA1, PHA2, PHB1, PHB2, PHC2
and FS002.
When using the FS002 remote control unit, the slope- up and slope- down times must be set
to 0 seconds.
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- 53 -
MAINTENANCE
LTN 160/200 normally need only a minimum of
maintenance. It is usually sufficient to blow it
clean with compressed air once a year and to
clean the fan air filter regularly.
If the machine is used in a dusty or dirty
environment, it should be blown clean more often.
The machine’s memory is battery- backed. If the
display shows the E06 error code, battery voltage is
low. See Error Codes on page 41.
NOTE that all guarantee obligations will be void
if the customer carries out any work on the
machine during the guarantee period to rectify any
faults.
bt07d109
Removing the filter
SPARE PARTS
The spare parts list for the LTN 160 and LTN 200 is published in a separate document with
filename / ordering no. 0468 290 990
cltn0de4
- 54 -
NOTES
notes
- 55 -
ESAB subsidiaries and representative offices
Europe
AUSTRIA
ESAB Ges.m.b.H
Vienna-Liesing
Tel: +43 1 888 25 11
Fax: +43 1 888 25 11 85
BELGIUM
S.A. ESAB N.V.
Brussels
Tel: +32 2 745 11 00
Fax: +32 2 726 80 05
THE CZECH REPUBLIC
ESAB VAMBERK s.r.o.
Prague
Tel: +420 2 819 40 885
Fax: +420 2 819 40 120
DENMARK
Aktieselskabet ESAB
Copenhagen-Valby
Tel: +45 36 30 01 11
Fax: +45 36 30 40 03
FINLAND
ESAB Oy
Helsinki
Tel: +358 9 547 761
Fax: +358 9 547 77 71
FRANCE
ESAB France S.A.
Cergy Pontoise
Tel: +33 1 30 75 55 00
Fax: +33 1 30 75 55 24
GERMANY
ESAB GmbH
Solingen
Tel: +49 212 298 0
Fax: +49 212 298 204
GREAT BRITAIN
ESAB Group (UK) Ltd
Waltham Cross
Tel: +44 1992 76 85 15
Fax: +44 1992 71 58 03
ESAB Automation Ltd
Andover
Tel: +44 1264 33 22 33
Fax: +44 1264 33 20 74
HUNGARY
ESAB Kft
Budapest
Tel: +36 1 20 44 182
Fax: +36 1 20 44 186
ITALY
ESAB Saldatura S.p.A.
Mesero (Mi)
Tel: +39 02 97 96 81
Fax: +39 02 97 28 91 81
THE NETHERLANDS
ESAB Nederland B.V.
Utrecht
Tel: +31 30 248 59 22
Fax: +31 30 248 52 60
NORWAY
AS ESAB
Larvik
Tel: +47 33 12 10 00
Fax: +47 33 11 52 03
POLAND
ESAB Sp.z.o.o
Warszaw
Tel: +48 22 813 99 63
Fax: +48 22 813 98 81
PORTUGAL
ESAB Lda
Lisbon
Tel: +351 1 837 1527
Fax: +351 1 859 1277
SLOVAKIA
ESAB Slovakia s.r.o.
Bratislava
Tel: +421 7 44 88 24 26
Fax: +421 7 44 88 87 41
SPAIN
ESAB Ibérica S.A.
Alcobendas (Madrid)
Tel: +34 91 623 11 00
Fax: +34 91 661 51 83
SWEDEN
ESAB Sverige AB
Gothenburg
Tel: +46 31 50 95 00
Fax: +46 31 50 92 22
ESAB International AB
Gothenburg
Tel: +46 31 50 90 00
Fax: +46 31 50 93 60
SWITZERLAND
ESAB AG
Dietikon
Tel: +41 1 741 25 25
Fax: +41 1 740 30 55
North and South America
Asia/Pacific
CHINA
Shanghai ESAB A/P
Shanghai
Tel: +86 21 6539 7124
Fax: +86 21 6543 6622
INDIA
ESAB India Ltd
Calcutta
Tel: +91 33 478 45 17
Fax: +91 33 468 18 80
INDONESIA
P.T. Esabindo Pratama
Jakarta
Tel: +62 21 460 01 88
Fax: +62 21 461 29 29
MALAYSIA
ESAB (Malaysia) Snd Bhd
Selangor
Tel: +60 3 703 36 15
Fax: +60 3 703 35 52
SINGAPORE
ESAB Singapore Pte Ltd
Singapore
Tel: +65 861 43 22
Fax: +65 861 31 95
ESAB Asia/Pacific Pte Ltd
Singapore
Tel: +65 861 74 42
Fax: +65 863 08 39
Representative offices
BULGARIA
ESAB Representative Office
Sofia
Tel/Fax: +359 2 974 42 88
EGYPT
ESAB Egypt
Dokki-Cairo
Tel: +20 2 390 96 69
Fax: +20 2 393 32 13
ROMANIA
ESAB Representative Office
Bucharest
Tel/Fax: +40 1 322 36 74
RUSSIA- CIS
ESAB Representative Office
Moscow
Tel: +7 095 937 98 20
Fax: +7 095 937 95 80
ESAB Representative Office
St Petersburg
Tel: +7 812 325 43 62
Fax: +7 812 325 66 85
Distributors
For addresses and phone
numbers to our distributors in
other countries, please visit our
home page
www.esab.com
SOUTH KOREA
ESAB SeAH Corporation
Kyung-Nam
Tel: +82 551 289 81 11
Fax: +82 551 289 88 63
UNITED ARAB EMIRATES
ESAB Middle East
Dubai
Tel: +971 4 338 88 29
Fax: +971 4 338 87 29
ARGENTINA
CONARCO
Buenos Aires
Tel: +54 11 4 753 4039
Fax: +54 11 4 753 6313
BRAZIL
ESAB S.A.
Contagem-MG
Tel: +55 31 3369 4333
Fax: +55 31 3369 4440
CANADA
ESAB Group Canada Inc.
Missisauga, Ontario
Tel: +1 905 670 02 20
Fax: +1 905 670 48 79
MEXICO
ESAB Mexico S.A.
Monterrey
Tel: +52 8 350 5959
Fax: +52 8 350 7554
USA
ESAB Welding & Cutting Products
Florence, SC
Tel: +1 843 669 44 11
Fax: +1 843 664 44 58
ESAB AB
SE- 695 81 LAXÅ
SWEDEN
Phone +46 584 81 000
www.esab.com
031021