LOKERMANN GRAND ARC 400 CEL User manual

USER MANUAL
INVERTER Based Welding Machines
IMPORTANT: Read this OPERATOR MANUAL together
with PRESCRIPTION AND COMPLIANCE MANUAL before
to use this equipment. In case of loss one of two parts
contact immediately your dealer.
Allow the operator to consult this manual.
GRAND ARC
400 CEL

1 INSTALLATION WARNING
2 OVERVIEW
2.1 Features
2.2 Technical Data
2.3 Brief Introduction
2.4 Duty cycle and Over-heat
2.5 Working Principle
2.6 Volt-Ampere Characteristic
3 INSTALLATION & OPERATION
3.1 Layout for the front and rear panel
3.2 Installation & Operation for MMA Welding
3.2.1 Set up installation for MMA Welding
3.2.2 Operation for MMA Welding
3.2.3 MMA Welding
3.2.4 MMA Welding Fundamentals
3.2.5 MMA Welding trouble shooting
3.3 Installation & Operation for TIG Welding
3.3.1 Set up installation for TIG Welding
3.3.2 Operation for TIG Welding
3.3.3 TIG Welding Fundamentals
3.3.4 DC TIG Welding trouble shooting
3.4 Operation environment
3.5 Operation Notices
4 MAINTENANCE & TROUBLESHOOTING
4.1 Maintenance
4.2 Troubleshooting
4.3 List of error code
4.4 Electrical schematic drawing

1. Installation warning
This machine is certified according to 60974-10:2014 Arc Welding Equipment Part 10: Electromagnetic
compatibility (EMC) requirement and the EUT belongs to Group 2 Class A.
WARNING: This Class A equipment is intended for industrial use and it is not intended for use in
residential locations where the elctrical power is provided by the public low-voltage supply system.
There may be potential difficulties in ensuring electromagnetic compatibility in those locations, due to
conducted as well as radiated disturbances.
WARNING: This equipment does not comply with IEC 61000-3-12. If it is connected to a public low-
voltage system, it is the responsability of the installer or user of the equipment to ensure, by consultation
with the distribution network operator if necessary, that the equipment may be connected.
Assessment of area
Before installing arc welding equipment the user shall make an assessment of potential
electromagnetic problems in the surrounding area. The following shall be taken into account:
a) other supply cables, control cables, signalling and telephone cables, above, below and
adjacent to the arc welding equipment;
b) radio and television transmitters and receivers;
c) computer and other control equipment;
d) safety critical equipment, for example guarding of industrial equipment;
e) the health of the people around, for example the use of pacemakers and hearing aids;
f) equipment used for calibration or measurement;
g) the immunity of other equipment in the environment. The user shall ensure that other
equipment being used in the environment is compatible. This may require additional
protection measures;
h) the time of day that welding or other activities are to be carried out.
The size of the surrounding area to be considered will depend on the structure of the building
and other activities that are taking place. The surrounding area may extend beyond the
boundaries of the premises.
Methods of reducing emissions-Public supply system
Arc welding equipment should be connected to the public supply system according to this manual
recommendations. If interference occurs, it may be necessary to takeadditional precautions such as
filtering of the public supply system. Consideration should be given to shielding the supply cable of
permanently installed arc welding equipment, in metallic conduit or equivalent. Shielding should be
electrically continuous throughout its length. The shielding should be connected to the welding power
source so that good electrical contact is maintained between the conduit and the welding power
source enclosure.

Maintenance of the arc welding equipment
The arc welding equipment should be routinely maintained according to this manual
recommendations. All access and service doors and covers should be closed and properly
fastened when the arc welding equipment is in operation. The arc welding equipment should
not be modified in any way, except for those changes and adjustments covered in this manaul. In
particular, the spark gaps of arc striking and stabilising devices
should be adjusted and maintained according to our recommendations.
Welding cables
The welding cables should be kept as short as possible and should be positioned close
together, running at or close to the floor level.
Equipotential bonding
Bonding of all metallic objects in the surrounding area should be considered. However,
metallic objects bonded to the work piece will increase the risk that the operator could receive
an electric shock by touching these metallic objects and the electrode at the same time. The
operator should be insulated from all such bonded metallic objects.
Earthing of the workpiece
Where the workpiece is not bonded to earth for electrical safety, nor connected to earth
because of its size and position, for example, ship’s hull or building steelwork, a connection
bonding the workpiece to earth may reduce emissions in some, but not all instances. Care should be
taken to prevent the earthing of the workpiece increasing the risk of injury to users or damage to other
electrical equipment. Where necessary, the connection of the workpiece to earth should be made by
a direct connection to the workpiece, but in some countries where direct connection is not permitted,
the bonding should be achieved by suitable capacitance, selected according to national regulations.
Screening and shielding
Selective screening and shielding of other cables and equipment in the surrounding area may
alleviate problems of interference. Screening of the entire welding area may be considered for
special applications.

2 Overview
2
.1 Features

Capable of welding with Lift Tig Mode.

Designed for
using cellulose welding rods.

Selectable VRD Protection for increased safety.

Adjustable arc force, hot start & anti-stick for
greater control and ease of use .

Digital current display meter for accurate pre-
setting and feedback of welding param- eters &
output.

Phase loss protection prevents damage as
machine automatically shuts down if power
supply phase loss occurs.

Temperature, voltage and current sensors for
increased reliability & safety.

Light,weight and compact design, ideal for
portable applications

Designed to work with diesel generators and
to avoid failures due to its voltage spikes.

Power source wind tunnel cooling construction
for protection against environmental contamination
2.2 Technical Data
Models
Parameters
GRAND ARC 400 CEL
Power Supply Voltage (V) 3~380V/400V±10%
Frequency(HZ) 50/60
Rated input current(A) 38MMA/28 TIG
Rated input power（KW）16.1 MMA/11.7 TIG
Duty cycle (40℃10 min)60% 400A
100% 310A
Welding Current Range(A) 20-400
No Load Voltage(V) 94MMA/22 TIG
Efficiency(%) ≥80%
Power Factor 0.7
Insulation class H
Protection class IP23
Cooling
AF
Net Weight(Kg) 22
Dimensions(mm)
570*280*450
Electrode Diameter
φ1.6~φ6.0
Electrode Type 6010,6011,6013,7018 etc.
Note: The above parameters are subject to change with future machine improvement!

2
.3 Brief Introduction
M
MA series of welding machines adopt the latest Pulse Width Modulation (PWM) technology
a
nd the Insulated Gate Bipolar Transistor (IGBT) power modules. It uses switching frequencies in
t
he 20KHz-50KHz ranges so as to replace the traditional line-frequency transformer type welding
m
achines. Thus, machines are characterized with portability, small size, lightweight, low energy
c
onsumption and noise, etc.
M
MA series of welding machines has excellent performance: constant current output makes
w
elding arc more stab le; fast dynamic response speed reduces the impact from the arc length
f
luctuation to the current; accurate stepless current adjustment and pre-setting function. There are als
o
s
ome automatic protection functions for under voltage, over current, over heat, etc. inside the welder
,
w
hen the problems listed before occurred, the alarm light on the front panel is on and at the same
t
ime the output current will be cut off. It can self-protect, prolong the us efull life, greatly improved
t
he reliability and pract icality of the welding machine.
M
MA series of welding machines can also realize TIG operation. While MMA operation, if the
e
lectrode touches workpiece over two seconds, the welding current will drop to the minimum curren
t
a
utomatically to protect the electro de. While TIG operation, the minimum current will be outputted
f
irstly until the arc is ignited by lifting method, the output current will rise to the preset value, which
c
an protect the electrode.
M
MA series of welding machines is widely used in Petroleum, chemical, mechanical,
s
hipbuilding, architecture, boiler, pressure container, military industry and Maintenance work, etc.
T
his machine has high duty cycle even in the 40℃, which can keep the continuous operation. The
f
rame is Stability of the machine,which can keep working under high temperature and corrosion
e
nvironment.
MMA: Manual Metal Arc welding;
PWM: Pulse-Width Modulation;
IGBT: Insulation Gate Bipolar Transistor;
TIG: Tungsten Inert Gas welding.
2
.4 Duty cycle and Over-heat
T
he letter “X” stands for Duty Cycle, which is defined as the portion of the time a welding machine
c
an weld continuously with it’s rated output current within a certain time cycle (10 minutes).
T
he relation between the duty cycle “X” and the output welding current “I” is shown as the right
f
igure.
I
f the welding machine is overheating, the IGBT over -heat protection sensing will send a signal to
t
he welding machine control unit to cut the output welding current OFF and light the over-heat pilot
l
amp on the front panel. In that case, the machine should not be welding for 10-15 minutes to cool
d
own with the fanrunning. When operating the machine again, the welding output current or the dut
y
c
ycle should be reduced.

2
.5 Working Principle
T
he working principle of MMA series of welding machines is shown in the following figure. Three-
p
hase 380V line frequency AC is rectified into DC, then is converted to medium frequency AC by
i
nverter device (IGB T), after reducing voltage by medium transformer (the main transformer) and
r
ectified by medium frequency rectifier (fast recovery diode), and is outputted by inductance filtering.
T
he circuit adopts current feedback control technology to insure current output stability. Meanwhile,
t
he welding current parameters can be adjusted continuously and steplessly to meet with the
r
equirements of welding craft.
2
.6 Volt-Ampere Characteristic
M
MA series of welding machines has excellent volt-ampere characteristic. Referring to the
f
ollowing graph. In MMA welding, the relation between the rated loading voltage U2and welding
c
urrent I2 is as follows:
When I2≤600A，U2＝20＋0.04 I2（V）；When I2＞600A，U2＝44（V）.
66
44
20
0 600 I
2
（A）
U
2
（V）
Working
point
Volt-ampere characteristic
The relation of the rated loading
voltage&welding current
Rectify Inverter
Medium
frequency
transformer
Medium
frequency
rectify
Hall device
Current positive-
feedback control
Three-phase, AC DC AC DC
380V，50Hz
AC DC
U0

3 Installation & Operation
3
.1 Layout for the front and rear panel
（1）Negative (-) welding power output connection socket.
（2）Positive (+)
（3）Input power cable.
（4）Power switch: control the power Supply on and off.
（5）Welding current control knob.
（6）Digital current display meter.
（7）Power indicator: Lights when input power connected and machine switched on.
（8）Alarm indicator. *
（9）Welding output mode button: Sets power source in MMA, MMA VRD* or
Lift TIG* mode.
（10）MMA mode indicator.
（11）MMA VRD mode indicator.
（12）Lift TIG mode indicator.
（13）Arc Force control knob. *
（14）Hot Start control knob. *
*Denotes more detailed explanation of function to follow.
F
urther Controls Explained
A
larm indicator
L
ights when over voltage, over current, input phase loss or electrical overheating (due to
e
xceeding duty cycle) is detected and protection is activated.
W
hen protection is activated, welding output will be disabled until the safety system senses
t
he overload has reduced sufficiently and indicator lamp goes out. May also trigger if machine
e
xperiences an internal power circuit failure.
welding power output connection socket.

A
rc Force control knob
A
n MMA welding power source is designed to produce constant output current (CC). This mean
s
w
ith different types of electrode and arc length; the welding voltage varies to keep the current
c
onstant. This can cause instability in some welding conditions as MMAwelding electrodes will hav
e
a
minimum voltage they can operate with and still have a stable arc.
A
rc Force control boosts the welding power if its senses the welding voltage is getting too low. The
h
igher the arc force adjustment, the higher the minimum voltage that the power source will allow.
T
his effect will also cause the welding current to increase. 0 is Arc Force off, 10 is maximum Ar
c
F
orce. This is practically useful for electrode types that have a higher operating voltage requirement
o
r joint types that require a short arc length such as out of position welds.
H
ot Start control knob
H
ot start provides extra power when the weld starts to counteract the high resistance of the electrod
e
a
nd workpiece as the arc is started.
L
ift TIG Mode
L
ift TIG is an arc ignition system for basic TIG welding that removes the need to “scratch”
s
tart or strike the tungsten on the work piece to start the arc, which can have a negative effect on
t
he weld quality due to tungsten contamination. Lift arc starting works by gently touching the
t
ungsten on the work piece andthen lifting it off. The control circuit will sense whenthe tungsten
i
s removed from the work piece and send a pulse of electricity through the torch that will cause
t
he TIG arc to initiate.
V
RD Function
V
RD stands for Voltage Reduction Device. This is a safety system that reduces the output voltage
f
rom the welding terminals in MMA mode while the welding output is not in use, to reduce the risk
o
f electric shock from the live output voltage. The disadvantage of this system is that it makes the
s
triking of the arc more difficult, especially on restarts and with some types of electrode such as low
h
ydrogen electrodes.
3
.2 Installation & Operation for MMA Welding
3.2.1 Set up installation for MMA Welding
C
onnection of Output Cables Two sockets are available on this welding machine. For MMA weldin
g
t
he electrode holder is shown be connected to the positive socket, while the earth lead (work piece)
i
s connected to the negative socket, this is known as DCEP. However various electrodes require a
d
ifferent polarity for optimum results and careful attention should be paid to the polarity, refer to th
e
e
lectrode manufacturers information for the correct polarity.
D
CEP: Electrode connected to “+”output socket.
D
CEN: Electrode connected to“-”output socket.

(
1) Connect the earth lead to “-”,tighten clockwise;
(
2) Connect the earth clamp to the work piece. Contact with the work piece must be firm contact
with clean, bare metal, with no corrosion, paint or scale at the contact point.
(
3) Connect the electrode lead to “+”,tighten clockwise;
(
4) Each machine is equipped with a power cable should be based on the input voltage welding
power cable connected to the appropriate position, not to pick the wrong voltage;
(
5) With the corresponding input power supply terminal or socket good contact and prevent
oxidation;
(
6) With a multi meter measure the input voltage is within the fluctuation range;
(
7) The power ground is well grounded.
3.2.2 Operation for MMA Welding
(
1) According to the above method to install is correct, turn the power switch, so that the power
switch is “ON” position, then the power indicator light, the fan comes on, the device work
properly.
(
2) Select the MMA /MMAVRD function with the LIFT TIG/MMA/MMA VRD selector switch.
(
3) Set the welding current relevant to the electrode type and size being used as recommended by
the electrode manufacturer.
(
4) Set welding parameters (hot start and arc force) as required following instructions in the previou
s
section.
(
5) Place the electrode into the electrode holder and clamp tight.
(
6) Strike the electrode against the work piece to create and arc and hold the electrode steady to
maintain the arc.
(
7) Commence welding. If necessary, readjust the Weld Current control to obtain the welding
condition required.
(
8) After completion of welding the Power Source should be left turned ON for 2 to 3 minutes. Thi
s
allows the fan to run and cool the internal components.
(
9) Switch the ON/OFF Switch (located on the rear panel) to the OFF position.

N
OTE:

Note the polarity of wiring, the general DC welding wire in two ways. Selected according to th
e
technical re quirements of welding the appropriate connection, if you choose incorrectly will
result in arc instability and spatter large adhesion and other phenomena, such cases can be quic
kly
reversed to joints.

If the work piece distance from the welding machine, the second line(electrode holder and
ground) is longer, so choose the appropriate conductor cross -sectional area should be larger to
reduce cable voltage drop.
3
.2.3 MMA Welding
O
ne of the most common types of arc welding is manual metal arc welding (MMA) or stick welding
.
A
n electric current is used to strike an arc between the base material and a consumable electrode ro
d
o
r ‘stick’. The electrode rod is made of a material that is compatible with the base material being
w
elded and is covered with a flux tha t gives off gaseous vapours that serve as a shielding gas and
p
roviding a layer of slag, both of which protect the weld area from atmospheric contamination. The
e
lectrode core itself acts as filler material the residue from the flux that forms slag coverin g over th
e
w
eld metal must be chipped away after welding.
●The arc is initiated by momentarily touching the electrode to the base metal.
●The heat of the arc melts the surface of the base metal to form
a molten pool at the end of the electrode.
●The melted electrode metal is transferred across the arc into
the molten pool and becomes the deposited weld metal.
●The deposit is covered and protected by a slag which comes
from the electrode coating.
●
The arc and the immediate area are enveloped by an
atmosphere of protective gas.
.

Manual metal arc (stick) electrodes have a solid metal wire cor
e
and a flux coating. These electrodes are identified by the wire
diameter and by a series of letters and numbers. The letters and
numbers identify the m etal alloy and the intended use of the
electrode.
The Metal Wire Core works as conductor of the current that
maintains the arc. The core wire melts and is deposited into the
welding pool.
The covering on a shielded metal arc welding electrode is calle
d
Flux.
The flux on the electrode performs many diferent functions.
These include:
●producing a protective gas around the weld area
●providing fluxing elements and deoxidizer
●creating a protective slag coating over the weld as it cools
●establishing arc characteristics
●adding alloying elements.
Covered electrodes serve many purposes in addition to
filler metal to the molten pool. These additional functions are
provided mainly by the covering on the electrode.
3.2.4 MMA WeldingFundamentals
Electrode Selection
As a general rule, the selection of an electrode is straight forward,in that it is only a matter of selectin
g
an electrode of similar composition to the parent metal. However, for some metals there is a choice
of several electrodes, each of which has particular properties to suit specific classes of work. It is
recommend to consult your welding supplier for the correct selection of electrode.
Electrode Size
The size of the electrode genera lly depends on
the thickness of the section being welded, and
the thicker the section the larger the electrode
required. The table gives the maximum size of
electrodes that maybe used for various
thicknesses of section base on using a general
purpose type 6013 electrode.
AverageThickness
of Material
MaximumRecommended
Electrode Diameter
1.0-2.0 mm
2.5 mm
2.0-5.0 mm
3.2 mm
5.0-8.0 mm
4.0 mm
>8.0 mm
5.0 mm

Welding Current (Amperage)
Correct current selection for a particular job is
an important factor in arc welding.With the
current set too low, difficulty is experienced in
striking and maintaining astable arc. The
electrode tends to stick to the work, penetratio
n
is poor and beads with a distinct rounded
profile will be deposited.Too high current is
accompanied by overheating of the electrode
resulting undercut and burning through of the base metal and producing excessive spatter. Normal
current for a particular job may be considered as the maximum, which can be used without burning
through the work, over-heating the electrode or producing a rough spattered surface.The table show
s
current ranges generally recommended for a general purpose type 6013 electrode.
Arc Length
To strike the arc, the electrode should be gently scraped on the work until the arc is established.
Ther is a simple rule for the proper arc length; it should be the shortest arc that gives a good surface
to the weld. An arc too long reduces penetration, produces spatter and gives a rough surface finish t
o
the weld. An excessively short arc will cause sticking of the electrode and result in poor quality
welds. General rule of thumb for down hand welding is to have an arc length no greater than the
diameter of the core wire.
Electrode Size
ø mm
Current Range
(Amps)
2.5 mm
60-95
3.2 mm
100-130
4.0 mm
130-165
5.0 mm
165-260

Electrode Angle
T
he angle that the electrode makes with the work is important to ensure a smooth, eve n transfer of
m
etal. When welding in down hand, fillet, horizontal or overhead the angle of the electrode is
g
enerally between 5and 15 degrees towards the direction of travel. When vertical up welding the
a
ngle of the electrode should be between 80 and 90 degrees to the work piece.

Travel Speed
T
he electrode should be moved along in the direction of the joint being welded at a speed that will
g
ive the size of run required. At the same time, the electrode is fed downwards to keep the correct
arc
length at all times. Excessive travel speeds lead to poor fusion, lack of penetration etc, while too
slow
a rate of travel will frequently lead to arc instability,slag inclusions and poor mechanical
p
roperties.

Material and Joint Preparation
T
he material to be welded should be clean and free of any moisture, paint, oil, grease, mill scale,
r
ust or any other material that will hinder the arc and contaminate the weld material. Joint
p
reparation will depend on the method used include sawing, punching, shearing, machining, flame
c
utting and others. In all casesedges should be clean and free of any contaminates. The type of joint
w
ill be determined by the chosen application.

3
.2.5 MMA Weldingtrouble shooting
T
he following chart addresses some of the common problems of MMA welding. In all cases of
e
quipment malfunction, the manufacturer’s recommendations should be strictly adhered to and
f
ollowed.
NO. Trouble Possible Reason Suggested Remedy
1 No arc
Incomplete welding circuit
Check earth lead is connected.
Check all cable connections.
No power supply
Check that the machine is switched
on and has a power supply
Wrong mode selected
Check the MMA selector switch is
selected
2
Porosity −small
cavities or holes
resulting from gas
pockets in weld
metal
Arc length too long
Shorten the arc length
Work piece dirty,
contaminated or moisture
Remove moisture and materials like
paint, grease, oil, and dirt, including
mill scale from base metal
Damp electrodes
Use only dry electrodes
3 Excessive Spatter Amperage too high
Decrease the amperage or choose a
larger electrode
Arc length too long Shorten the arc length
4 Weld sits on top,
lack of fusion
Insufficient heat input Increase the amperage or choose a
larger electrode
Work piece dirty,
contaminated or moisture
Remove moisture and materials like
paint, grease, oil, and dirt, including
mill scale from base metal
Poor welding technique
Use the correct welding technique or
seek assistance for the correct
technique
5 Lack of penetration
Insufficient heat input
Increase the amperage or choose a
larger electrode
Poor welding technique
Use the correct welding technique or
seek assistance for the correct
technique
Poor joint preparation
Check the joint design and fit up,
make sure the material is not too
thick. Seek assistance for the correct
joint design and fit up
6
Excessive
penetration - burn
through
Excessive heat input
Reduce the amperage or use a
smaller electrode
Incorrect travel speed
Try increasing the weld travel speed
7
Uneven weld
appearance
Unsteady hand, wavering
hand
Use two hands where possible to
steady up, practise your technique
8
Distortion −
movement of base
metal during
welding
Excessive heat input
Reduce the amperage or use a
smaller electrode
Poor welding technique
Use the correct welding technique or
seek assistance for the correct
technique
Poor joint preparation and or
joint design
Check the joint design and fit up,
make sure the material is not too
thick. Seek assistance for the correct
joint design and fit up
9
Electrode welds
with different or
Incorrect polarity
Change the polarity, check the
electrode manufacturer for correct
polarity

3.3
Installation & Operation for TIG Welding
3
.3.1 Set up installation for TIG Welding
(
1) Switch the ON/OFF Switch (located on the rear panel) to OFF.
(
2) Connect the earth lead to “+”,tighten clockwise;
(
3) Connect the earth clamp to the work piece. Contact with the work piece must be firm contact
with clean, bare metal, with no corrosion, paint or scale at the contact point.
(
4) Connect the TIG torch cable to “-”, tighten clockwise;
(
5) Connect valve TIG torch gas line to the regulator, ensuring all connections are tight.
(
6) Open gas cylinder valve and adjust regulator, flow should be between 5-10 l/min depending on
application. Re-check regulator flow pressure with torch valve open as static gas flow setting
may drop once gas is flowing.
(
7) Each machine is equipped with a power cable should be based on the input voltage welding
power cable connected to the appropriate position, not to pick the wrong voltage;
(
8) With the corresponding input power supply terminal or sock et good contact and prevent
oxidation;
(
9) With a multi meter measure the input voltage is within the fluctuation range;
(
10)The power ground is well grounded.
N
OTE:

When TIG operation, the shielded gas is inputted to welding gun directly.

Secure the gas cylinder in an upright position by chaining them to a stationary support to
prevent falling or tipping.
3
.3.2 Operation for TIG Welding
(
1) According to the above method to install is correct, turn the power switch to the “ON” position
,
the power L.E.D. light should illuminate, the fan comes on, the device work properly.
(
2) Select the LIFT TIG function with the LIFT TIG/MMA/MMA VRD selector switch.
(
3) Set the required output current using the knob (5)
(
4) The tungsten must be ground to a blunt point in order to achieve optimum w elding results. It is
critical to grind the tungsten electrode in the direction the grinding wheel is turning.
(
5) Install the tungsten with approximately 3mm to 7mm sticking out from the gas cup, ensuring yo
u
have correct sized collet.
(
6) Tighten the back cap
(
7) Commence welding. If necessary, readjust the Weld Current control to obtain the welding
condition re-quired.
(
8) After completion of welding the Power Source should be left turned ON for 2 to 3 minutes. Thi
s
allows the fan to run and cool the internal components.
(
9) Switch the ON/OFF Switch (located on the rear panel) to the OFF.

3
.3.3 TIG Welding Fundamentals
S
tricking the arc for TIG Operation: when tungsten electrode touches the workpiece, the short-
c
ircuit current is only 28A . After generating arc, current can rise to the setting welding current. If
t
he tungesten electrode touches the workpiece when welding, the current will drop to 5A within 2s,
w
hich can reduce tungsten waste, prolong the using life of the tungsten electrode, and prevent
t
ungsten clipping.

Scraping arc

Tungsten Electrode Current Ranges
Electrode Diameter
DC Current
1.0mm
25 - 85
1.6mm
50 - 160
2.4mm
160 - 250
3.2mm
250 - 400
4.0mm
400 - 500

Shielding Gas Selection
Alloy
Shielding Gas
Carbon Steel
Welding Argon
Stainless Steel
Welding Argon
Nickel Alloy
Welding Argon
Copper
Welding Argon
Titanium
Welding Argon

Tungsten Electrode Types
Electrode Type
(Ground Finish) Welding Application Features Colour Code
Thoriated 2%
DC welding of mild steel,
stainless steel and copper.
Excellent arc starting, long life,
high current carrying capacity. Red
Ceriated 2%
AC & DC welding of mild
steel, stainless steel, copper
aluminium magnesium and
their alloys.
Longer life, more stable arc,
easier starting, wilder current
range, narrower more concen-
trated arc.
Grey


TIG Welding Parameters for Steel
Base Metal
Thickness
DC Current
Electrode
Diameter
Filler Rod
Diameter
Argon Gas
Flow Rate
Mild Steel
Stainless Steel
1.0mm
40-50
25-35
1.0mm
1.6mm
5LPM
1.6mm
70-90
50-70
1.6mm
1.6mm
7LPM
3.2mm
90-115
90-110
1.6mm
2.4mm
7LPM
3
.3.4 DC TIG Welding trouble shooting
T
he following chart addresses some of the common problems of DC TIG welding. In all cases of
e
quipment malfunction, the manufacturer’s recommendations should be strictly adhered to and
f
ollowed.
NO. Trouble Possible Reason Suggested Remedy
1 Tungsten burning
away quickly
Incorrect Gas or No Gas
Use pure Argon. Check cylinder has
gas, connected, turned on and torch
valve is open
Inadequate gas flow
Check the gas is connected, check
hoses, gas valve and torch are not
restricted.
Back cap not fitted correctly
Make sure the torch back cap is
fitted so that the o-ring is inside the
torch body
Torch connected to DC +
Connect the torch to the DC- output
terminal
Incorrect tungsten being used
Check and change the tungsten type
if necessary
Tungsten being oxidised after
weld is finished
Keep shielding gas flowing 10–15
seconds after arc stoppage. 1 second
for each 10amps of weld current.
2 Contaminated
tungsten
Touching tungsten into the
weld pool
Keep tungsten from contacting weld
puddle. Raise the torch so that the
tungsten is off of the work piece 2 -
5mm
Touching the filler wire to the
tungsten
Keep the filler wire from touching
the tungsten during welding, feed the
filler wire into the leading edge of
the weld pool in front of the tungsten
3
Porosity - poor
weld appearance
and colour
Wrong gas / poor gas flow
/gas leak
Use pure argon. Gas is connected,
check hoses, gas valve and torch are
not restricted. Set the gas flow
between 6-12 l/min. Check hoses
and fittings for holes, leaks et
Contaminated base metal
Remove moisture and materials like
paint, grease, oil, and dirt from base
metal
Contaminated filler wire
Remove all grease, oil, or moisture
from filler metal
Incorrect filler wire
Check the filler wire and change if
necessary

Yellowish residue /
smoke on the
alumina nozzle &
discoloured tungsten
Incorrect Gas
Use pure Argon gas
Inadequate gas flow
Set the gas flow between 10 - 15 l/min
flow rate
Alumina gas nozzle too small
Increase the size of the alumina gas
nozzle
Unstable Arc during
DC welding
Torch connected to DC +
Connect the torch to the DC- output
terminal
Contaminated base metal
Remove materials like paint, grease,
oil, and dirt, including mill scale from
base metal.
Tungsten is contaminated
Remove 10mm of contaminated
tungsten and re grind the tungsten
Arc length too long
Lower torch so that the tungsten is off
of the work piece 2 - 5mm
Arc wanders during
DC welding
Poor gas flow
Check and set the gas flow between 10
- 15 l/min flow rate
Incorrect arc length Lower torch so that the tungsten is off
of the work piece 2 - 5mm
Tungsten incorrect or in poor
condition
Check that correct type of tungsten is
being used. Remove 10mm from the
weld end of the tungsten and re sharpen
the tungsten
Poorly prepared tungsten
Grind marks should run lengthwise
with tungsten, not circular. Use proper
grinding method and wheel.
Contaminated base metal or
filler wire
Remove contaminating materials like
paint, grease, oil, and dirt, including
mill scale from base metal. Remove all
grease, oil, or moisture from filler metal
Arc difficult to start
or will not start DC
welding
Incorrect machine set up
Check machine set up is correct
No gas, incorrect gas flow
Check the gas is connected and cylinder
valve open, check hoses, gas valve and
torch are not restricted. Set the gas flow
between 10 - 15 l/min flow rate
Incorrect tungsten size or type
Check and change the size and or the
tungsten if required
Loose connection
Check all connectors and tighten
Earth clamp not connected to
work
Connect the earth clamp directly to the
work piece wherever possible

3
.4 Operation environment
▲
Height above sea level ≤1000 M
▲
Operation temperature range -10～+40°C
▲
Air relative humidity is below 90 %( 20°C)
▲
Preferable site the machine some angles above the floor level, the maximum angle does not exce
ed
15℃.
▲
Protect the machine against heavy rain AND against direct sunshine.
▲
The content of dust, acid, corrosive gas in the surrounding air or substance cannot exceed normal
standard.
▲
Take care that there is sufficient ventilation during welding. There must be at least 30cm free
distance between the machine and wall.
3
.5 Operation Notices
▲
Read Section §1 carefully before starting to use this equipment.
▲
Connect the ground wire with the machine directly.
▲
Ensure that the input is three-phase: 50/60Hz, 380V±10%.
▲
Before operation, none concerned people should not be around the working area and especially
c
hildren. Do not watch the arc in unprotected eyes.
▲
Ensure good ventilation of the machine to improve Duty Cycle.
▲
Turn off the engine when the operation finished for energy consumption efficiency.
▲
When power switch shuts off pro tectively because of failure. Don’t restart it until problem is
resolved. Otherwise, the range of problem will be extended.
▲
In case of problems, contact your local dealer if no authorized maintenance staff is available!
4 Maintenance & Troubleshooting
4
.1 Maintenance
I
n order to guarantee safe and proper operation of welding machines, they must be maintaine
d
r
egularly. Let customers understand the maintenance procedure of welding machines. Enabl
e
c
ustomers to carry on simple examination and inspections. Do your best to reduce the fault rate an
d
r
epair times of welding machines to lengthen service life of arc welding machine. Maintenance item
s
i
n detail are in the following table.
●
Warning: For safety while maintaining the machine, please shut off the main input power a
nd
w
ait for 5 minutes, until capacitors voltage already drop to safe voltage 36V!

Date
Maintenance items
Daily
examinati
on
Observe that the knobs and switches in the front and at the back of arc
welding machine are flexible and put correctly in place. If any knob has not
been put correctly in place, please correct. If you can't correct or fix the knob,
please replace immediately;
If any switch is not flexible or it can't be put correctly in place, please replace
immediately. Please get in touch with maintenance service department if there
are no accessories.
After turn -on power, watch/listen if the arc -welding machine has shaking,
whistle calling or peculiar smell. If there is one of the above problems, find out
the reason and clear it. If you can't find out the reason, please contact your local
service repair station or distributor/agent .
Observe that the display value of LED is intact. If the display number is not
intact, please replace the damaged LED. If it still doesn’t work, please maintain
or replace the display PCB.
Observe that the min/max values on LED agree with the set value. If there is
any difference and it has affected the normal welding results, please adjust it.
Check whether the fan is damaged and whether it is normal to rotate or
control. If the fan is damaged, please change immediately. If the fan does not
rotate after the machine is overheated, observe if there is something blocking
the blade. If it is blocked, please clear the problem. If the fan does not rotate
after getting rid of the above problems, you can poke the blade by the rotation
direction of fan. If the fan rotates normally, the start capacity should be
replaced. If not, change the fan.
Observe whether the fast connector is loose or overheated. If the arc- welding
machine has the above problems, it should be fastened or changed.
Observe whether the current output cable is damaged. If it is damaged, it
should be insulated or changed.
Monthly
examinati
on
Using the dry compressed air to clear the inside of arc welding machine.
Especially for clearing up the dusts on radiator, main voltage transformer,
inductors, IGBT modules, fast recover diodes, PCB’s, etc.
Check the screws and bolt s in the machine. If any is loose, please screw it
tight. If it is shaved, please replace. If it is rusty, please erase rust on all bolts to
ensure it works well.
Quarter-
yearly
examinati
on
Check whether the actual current accords with the displaying value. If they did
not accord, they should be regulated. The actual welding current value can be
measured by and adjusted by plier-type ampere meter.
Yearly
examinati
on
Measure the insulating impedance among the main circuit, PCB and case, if it
below 1MΩ, insulation is thought to be damaged and need to change, and need
to change or strengthen insulation.
4
.2 Troubleshooting

Before the welding machines aredispatched from the factory, they have already been teste
d
and calibrated accurately. It is forbidden for anyone who is not authorized by our compan
y
to do any change to the equipment!

Maintenance course must be operated carefully. If any wire becomes flexible or is misplaced, i
t
maybe potential danger to user!

Only professional maintenance staff that is authorized by our company could overhaul th
e
machine!

Be sure to shut off the Main Input Power before doing any repair work on the weldin
g
machine!

If there is any problem and there is no authorized professional maintenance personal on site
,
please contact local agent or the distributor!
If there are some simple troubles with the welding machine, you can consult the following chart: