WELDING INDUSTRIES Weldarc 200i DC User manual

MC109-40 RevB
Weldarc 200i DC
Weldarc 200i DC Stick/TIG Welder
Model No. MC109-0 (From serial no.M1092A*)
Operators Manual
08/20 MC109-40 RevB

Welding Industries of Australia
A division of ITW Australia Pty Ltd
ABN: 63 004 235 063
1300 300 884
[email protected]
welding.com.au
Weldwell New Zealand
A Division of ITW New Zealand
Telephone: [phone]
Email: [email protected]
weldwell.co.nz

Weldmatic 200i DC
Model No MC109 1
Contents
Section General Information Page
Safe Practices 2
1 Introduction 5
2 Receiving 6
3 Features 6
4 Specifications 7
5 Controls 9
6 Installation 15
7 Basic Welding Information 16
8 External Trouble Shooting 20
9 Service Information 21
9.1 Circuit Diagram 22
10 Assembly and Parts Lists
Power Source 23
11 Australian Warranty Information 26
12 New Zealand Warranty Information 27

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Read First
The information contained in this
manual is set out to enable you
to properly maintain your new
equipment and ensure that you obtain
maximum operating efficiency.
Please ensure that this information is
kept in a safe place for ready reference
when required at any future time.
When ordering spare parts, please
quote the model and serial number
of the power source and part number
of the item required. All relevant
numbers are shown in lists contained
in this manual. Failure to supply this
information may result in unnecessary
delays in supplying the correct parts.
Safety
Before this equipment is put into
operation, please read the Safe
Practices section of this manual.
This will help to avoid possible injury
due to misuse or improper welding
applications.
Plastic Handles on Power
Source
Please note that the handle fitted to
the Weldarc 200i inverter is intended
for carrying the equipment by hand
only.
DO NOT use this handle for
suspending or mounting the Weldarc
in any other manner.
Safe Practices When Using
Welding Equipment
These notes are provided in the interests
of improving operator safety. They should
be considered only as a basic guide to Safe
Working Habits. A full list of Standards
pertaining to industry is available from
the Standards Association of Australia,
also various State Electricity Authorities,
Departments of Labour and Industry or
Mines Department and other Local Health
or Safety Inspection Authorities may have
additional requirements. Australian Standard
AS1674.2 provides a comprehensive guide to
safe practices in welding.
Eye Protection
NEVER LOOK AT AN ARC WITHOUT
PROTECTION. Wear a helmet with
safety goggles or glasses with side shields
underneath, with appropriate filter lenses
protected by clear cover lens. This is a MUST
for welding, cutting, and chipping to protect
the eyes from radiant energy and flying
metal. Replace the cover lens when broken,
pitted, or spattered.
Recommended Shade Filter Lens
Amps TIG MMAW MIG
Pulsed
MIG
0-100 10 9 10 12-13
100-150 11 10 10 12-13
150-200 12 10-11 11-12 12-13
200-300 13 11 12-13 12-13
300-400 14 12 13 14
400-500 — 13 14 14
500 + — — 14 14

Weldmatic 200i DC
Model No MC109 3
Burn Protection
The welding arc is intense and visibly bright.
Its radiation can damage eyes, penetrate
light-weight clothing, reflect from light-
coloured surfaces, and burn the skin and
eyes. Burns resulting from gas-shielded arcs
resemble acute sunburn, but can be more
severe and painful.
Wear protective clothing – leather or heat
resistant gloves, hat, and safety-toed boots.
Button shirt collar and pocket flaps, and
wear cuffless trousers to avoid entry of
sparks and slag.
Avoid oily or greasy clothing. A spark may
ignite them. Hot metal such as electrode
stubs and work pieces should never be
handled without gloves.
Ear plugs should be worn when welding in
overhead positions or in a confined space.
A hard hat should be worn when others are
working overhead.
Flammable hair preparations should not be
used by persons intending to weld or cut.
Toxic Fumes
Adequate ventilation with air is essential.
Severe discomfort, illness or death can
result from fumes, vapours, heat, or oxygen
depletion that welding or cutting may
produce. NEVER ventilate with oxygen.
Lead, cadmium, zinc, mercury, and beryllium
bearing and similar materials when welded
or cut may produce harmful concentrations
of toxic fumes. Adequate local exhaust
ventilation must be used, or each person in
the area as well as the operator must wear
an air-supplied respirator. For beryllium, both
must be used.
Metals coated with or containing materials
that emit fumes should not be heated unless
coating is removed from the work surface,
the area is well ventilated, or the operator
wears an air-supplied respirator.
Work in a confined space only while it is
being ventilated and, if necessary, while
wearing air-supplied respirator.
Vapours from chlorinated solvents can be
decomposed by the heat of the arc (or
flame) to form phosgene, a highly toxic
gas, and lung and eye irritating products.
The ultra-violet (radiant) energy of the arc
can also decompose trichlorethylene and
perchlorethylene vapours to form phosgene.
Do not weld or cut where solvent vapours
can be drawn into the welding or cutting
atmosphere or where the radiant energy
can penetrate to atmospheres containing
even minute amounts of trichlorethylene or
percholorethylene.
Fire And Explosion Prevention
Be aware that flying sparks or falling slag can
pass through cracks, along pipes, through
windows or doors, and through wall or floor
openings, out of sight of the operator. Sparks
and slag can travel up to 10 metres from the arc.
Keep equipment clean and operable, free of
oil, grease, and (in electrical parts) of metallic
particles that can cause short circuits.
If combustibles are present in the work
area, do NOT weld or cut. Move the work if
practicable, to an area free of combustibles.
Avoid paint spray rooms, dip tanks, storage
areas, ventilators. If the work can not be
moved, move combustibles at least 10 metres
away out of reach of sparks and heat; or
protect against ignition with suitable and
snug-fitting fire-resistant covers or shields.
Walls touching combustibles on opposite
sides should not be welded on or cut. Walls,
ceilings, and floor near work should be
protected by heat-resistant covers or shields.

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A person acting as Fire Watcher must be
standing by with suitable fire extinguishing
equipment during and for some time after
welding or cutting if;
• Combustibles (including building
construction) are within 10 metres.
• Combustibles are further than 10 metres
but can be ignited by sparks.
• Openings (concealed or visible) in floors
or walls within 10 metres may expose
combustibles to sparks.
• Combustibles adjacent to walls, ceilings,
roofs, or metal partitions can be ignited
by radiant or conducted heat.
After work is done, check that area is free of
sparks, glowing embers, and flames.
A tank or drum which has contained
combustibles can produce flammable
vapours when heated. Such a container must
never be welded on or cut, unless it has first
been cleaned as described in AS.1674-2.
This includes a thorough steam or caustic
cleaning (or a solvent or water washing,
depending on the combustible’s solubility),
followed by purging and inerting with nitrogen
or carbon dioxide, and using protective
equipment as recommended in AS.1674-2.
Water-filling just below working level may
substitute for inerting.
Hollow castings or containers must be vented
before welding or cutting. They can explode.
Never weld or cut where the air may contain
flammable dust, gas, or liquid vapours.
Shock Prevention
Exposed conductors or other bare metal
in the welding circuit, or ungrounded
electrically alive equipment can fatally shock
a person whose body becomes a conductor.
Ensure that the equipment is correctly
connected and earthed. If unsure have the
equipment installed by a qualified electrician.
On mobile or portable equipment, regularly
inspect condition of trailing power leads
and connecting plugs. Repair or replace
damaged leads.
Fully insulated electrode holders should be
used. Do not use holders with protruding
screws. Fully insulated lock-type connectors
should be used to join welding cable lengths.
Terminals and other exposed parts of
electrical units should have insulated knobs
or covers secured before operation.

Weldmatic 200i DC
Model No MC109 5
1 Introduction
MMAW (Stick Welding)
Manual Metal Arc Welding (MMAW) is a
process where an arc is struck between a
flux-coated consumable electrode and the
work piece. The arc and the weld pool are
both shielded by gases generated by the flux
coating of the electrode.
The Weldarc 200i has been designed to
be used with 2.0mm, 2.5mm, 3.2mm and
4.0mm diameter electrodes. The smaller
electrodes are used when welding at lower
currents, such as sheet metal applications.
Increasing the electrode diameter permits
higher welding currents to be selected.
WIA supplies a wide range of mild steel and
special purpose electrodes which cater for home
workshop, rural, and industrial requirements.
Some popular AUSTARC electrodes are listed
below. The correctly selected AUSTARC
electrode will influence the quality of the weld,
and the stability of the arc.
Austarc 12P, Classification E4313-A
A popular general purpose electrode
used with ease in all positions, vertical up
or down. The smooth forceful arc makes
it an ideal electrode for all general mild
steel applications.
Austarc 13S, Classification E4313-A
A smooth running electrode with a soft arc,
particularly suited to light sheetmetal and
smooth mitre fillet welds.
Austarc 16TC, Classification E4916-A
A low hydrogen electrode with good
arc stability and out-of-position welding
characteristics. This electrode is ideal
for medium carbon steels, or steels of
unknown analysis.
Austarc 11, Classification E4311-A
A high cellulose electrode for all positional
welding, AC or DC. Particularly suited for
vertical and incline pipe welding where
complete root penetration is required.
Unicord 312, Classification ES312-16
A high tensile (50tsi), chromium nickel
electrode specially formulated for joining
all alloy steels and irons, and for tool and
die maintenance.
GTAW (TIG Welding)
Gas Tungsten Arc Welding (GTAW) is a
welding process where the arc is struck
between a non-consumable tungsten
electrode and the work piece. A ceramic
nozzle surrounds the tungsten electrode and
directs a flow of inert gas, usually Argon,
over the electrode and the weld zone. If
filler metal is required, it is hand fed into the
welding arc. The DC current output of the
Weldarc inverter is suitable for welding most
ferrous and non-ferrous metals.

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2 Receiving
Check the equipment received against the
shipping invoice to make sure the shipment
is complete and undamaged. If any damage
has occurred in transit, please immediately
notify your supplier.
The Weldarc inverter package contains;
• Weldarc Inverter Power Source
• Twist-lock Electrode Holder
• Work Clamp 3m
• (This) Operating Manual MC109-40.
• TIG Torch Complete with 8m cable with
twist-lock connection.
• TIG Consumable KIT
• Argon flow gauge regulator REG003
3 Features
3.1 Fan on Demand
The machine has Fan on Demand feature.
The fan will only operate when when the
temperature rise requires cooling. The Fan
will run during power up, and power down.
3.2 Voltage Reduction Device (VRD)
Whenever the welding output of the Weldarc
inverter is open circuit (ie not arcing), the
voltage across the welding leads is reduced
to a safe level. This provides an increased
level of safety to the welding operator during
operations such as changing the electrode.
The “VRD SAFE” indicator on the front
panel is on to confirm the output is in the
safe condition.
The term VRD refers to a “Voltage Reducing
Device”which complies with AS1674.2 for
Category “C” conditions.
The machine will be supplied with VRD enabled
or disabled, depending on the end market.
VRD Disabled
The open circuit output voltage is maximum
Volts DC. The ‘VRD SAFE’ indicator on the
front panel will only light up momentarily
during power up. Machine is supplied with
an orange tag on the supply lead advising
VRD is disabled.
VRD Enabled
When not welding the ‘VRD SAFE’
indicator on the front panel will come on
and the output voltage will be reduced
to approximately 23V, which is below the
required safe level of 35V DC.
Change VRD Function
If the VRD function does not suit the
application, the VRD can be enabled or
disabled by an authorised WIA service agent.
3.3 Power Factor Correction (PFC)
PFC provides a input power conditioner
system to smooth the input current.
On a conventional inverter machine the input
current presents in short high current pulses
every half mains cycle. These pulses, cause
input voltage drop, on extension leads and
generators.
The PFC spreads the current pulse over the
whole mains cycle.
The overall effect is PFC provides stable
operation, on challenging power supplies,
particularly on long supply leads and
generators.
INPUT
VOLTAGE
INPUT
CURRENT
WITHOUT PFC
INPUT
CURRENT
WITH PFC

Weldmatic 200i DC
Model No MC109 7
4 Specifications
Manufactured to Australian Standard AS60974-1
IEC60974-10 6.3.2 6.3.3.
TERM VALUE UNIT
Rated Input Voltage 220 - 240 V
Power Frequency 50/60 Hz
Rated Input Capacity 6KVA
Generator Capacity 6-8 KVA
Rated Maximum Supply Current Imax 25 A
Maximum Effective Supply Current Ieff 14 A
Output No Load Voltage 78 V
Supply Main Circuit Breaker 20 A
Supply Cable 2.5mm2 & Plug Rating 15 A
Extension Lead Rating 15 A
Open Circuit Voltage VRD Enabled: Uo = 13 - 17
VRD Disabled: Uo = 78 V
Rated Output 40 ° C
Stick MMA 180 A @ 27.2 Volts
99 A @ 24 Volts
30% Duty
100% Duty
TIG 200 A @ 18 Volts
110 A @ 14.4 Volts
30% Duty
100% Duty
Current Up Slope Time 0 - 15 S
Current Down slope Time 0 - 25 S
Pulse Frequency 2 - 200 Hz
Pulse Ratio Width Adjustment 10 - 90 %
Arc Force Control MMA 0-100%
of preset value
0-100%
of preset value
Arc Start MMA 0-100% 0-100%
Post Gas Time 0 - 15 S
Pre Gas Time 0 - 5 S
Cooling Type Fan on Demand
Efficiency ≥85% n
Power Factor 0.99 Cos§
Insulation Degree H
Cover Protection Degree IP23S IP
Weight 9.4 kg

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Shipping Weight 17.5 kg
Dimension L × W × H 470 x 290 x 350 mm
Shipping Dimension L × W × H 550 x 190 x 390 mm
4 Specifications (cont)

%
Weldmatic 200i DC
Model No MC109 9
Fig 1 Weldarc 200i DC Controls
5 Controls
Power Switch
Located on the rear panel 1
12
11 10
1 VRD Safe Mode Indicator
When the machine is in MMA stick mode
the light will be on when the voltage across
the output terminals is reduced to safe
level. The VRD will operate in accordance
the requirements of AS1674.2 Category C
Environment.
57
2
3
9
6
8
4
2 Over Temperature Indicator
This light will come on if any internal thermal
protection devices have operated due to
overheating, caused by the duty cycle
being exceeded.
The machine will not weld but the fan will
continue to operate to cool the machine.
When a safe temperature has been reached,
the thermal protection device will reset and
welding can continue.
6.16.2

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3 Power On
This light will be on when the input supply is
turned on.
4 Latch Mode 2T/4T
Latch mode provides a 2 STEP or 4 STEP
trigger control while in TIG mode:
4.1 2 STEP
In this mode the torch trigger must be pressed
on to initiate welding and held on till welding
is finished.
Up slope and down slope, ignition current and
crater current cannot used in the 2 STEP.
4.2 STEP
In this mode the torch trigger switch
is pressed to start the arc.
The current will stay at the ARC
IGNITION setting.
When trigger is released the current
will increase to the WELDING CURRENT
setting, according to the UP SLOPE time.
Output will continue at WELDING
CURRENT setting.
When torch trigger is pressed again
then the weld output will decrease
down to CRATER CURRENT setting,
according to the DOWN SLOPE time.
Weld output will remain at CRATER
CURRENT until torch trigger is
released, then gas will flow for POST
GAS time.
Fig 3 Latch Mode–4 STEP
Time
Amps
IGNITION
IGNITION
CURRENT
CURRENT
PRE GAS
PRE GAS
POST GAS
POST GAS
UP SLOPE
UP SLOPE
WELDING CURRENT
WELDING CURRENT
DOWN SLOPE
DOWN SLOPE
CRATER
CRATER
CURRENT
CURRENT
Press +Hold
Torch Trigger
Press +Hold
Torch Trigger
Release
Torch Trigger
Release
Torch Trigger
Fig 2 Latch Mode–2 STEP
Time
Amps
PRE GAS
PRE GAS
POST GAS
POST GAS
WELDING CURRENT
WELDING CURRENT
Press +Hold
Torch Trigger
Release
Torch Trigger
5 Controls

Weldmatic 200i DC
Model No MC109 11
5 Adjustment Knob
This knob is used to adjust welding
parameters.
The knob primary function is to adjust the
welding current. Turning the knob will adjust
the weld current which is indicated on the
digital display.
Press and release the knob, will select one of
the additional welding parameters (see 10)
The selected parameter indicator will be lit
and then the parameter can be adjusted by
turning the knob. The parameter indicator
is held for about 4 seconds before reverting
back to normal current adjustment mode.
6 Weld Mode Selection
The Weld Mode can select between the two
mode of operation.
6.1 Stick MMA Mode
In this mode the machine performs as
a DC stick MMA welding machine. The
HOT START and ARC FORCE parameters
can be adjusted on the front panel.
6.2 TIG Mode
In this mode the machine will perform as
a DC TIG machine.
7 TIG Start Mode
Use This mode to select between High
Frequency (HF) start, or LIFT TIG start.
High Frequency (HF) arc start is when
the tungsten is near the work piece and
the torch trigger is pressed, then a high
energy spark is created to jump from
the tungsten to work piece and initiate
an Arc.
Lift TIG start the tungsten is touched to
the work piece and lifted to then start
the arc.
8 Pulse Mode
The machine can operate with flat DC
output, or an output that Pulses between
two DC currents. In Pulse TIG the parameters
for adjusting the pulse shape will be available
for adjustment.
Peak Current, Pulse Ratio, Frequency Hertz,
and Base Current can be adjusted, refer to
10.5
Pulse mode can be used for thin plate
welding, maintaining good penetration, but
with reduced Heat Effected Zone.
9 Amps Display
The digital display will show Amps while
adjusting current with knob 5, and then
display weld Amps while welding is in
progress.

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10 Welding Parameters
Press Adjustment Knob (5) to access
welding parameters.
10.1 Pre Gas
Pre gas flow can be set to a maximum
of 5 seconds, to allow gas flow before
Arc Start.
10.2 Ignition Current
While in 4 STEP latch mode the arc will
start and maintain the Ignition current
output until the trigger torch is released.
The IGNITION CURRENT can be more or
less than the WELD CURRENT setting.
Setting the IGNITION CURRENT high
can be useful for joint preheat.
10.3 Up Slope
The UP SLOPE time is the time taken
for the weld current to transition from
the IGNITION CURRENT value to WELD
CURRENT value. The time can be
adjusted from 0 to 15 seconds.
10.4 Welding Current
The setting for actual weld current.
10.5 Pulse Welding
Pulse welding allows the current to
be pulsed between two different
values, the frequency and ratio can be
adjusted. This feature can be used on
thin material.
10.5.1 Peak Current
Set the Peak current Amps when in
pulse mode.
10.5.2 Pulse Ratio
Set the ratio in % for the peak
current compared to the back
ground current. Range is 10%
to 90%.
10.5.3 Hertz
The frequency of the pulse can be
set, as number of pulses per second
(Hertz) 0.2Hz to 200Hz.
10.5.4 Base Current
Set the Base current Amps when in
pulse mode
10.5.5 Down Slope
The DOWN SLOPE time is the
time taken for the weld current
to transition from the WELDING
CURRENT value to CRATER
CURRENT value. The time can be
adjusted from 0 to 25 seconds.
Fig 4 Weldarc 200i DC Welding Parameters
5 Controls
%

Weldmatic 200i DC
Model No MC109 13
10.5.6 Crater Current
The current at the end of WELD can
be adjusted to a value which will
allow controlled finish of the weld.
The end of weld pool (Crater) can be
filled.
10.5.7 Post Gas
The Post Gas time can be adjusted
to allow gas to flow after weld has
stopped. This feature can be used to
provide a gas shield to the cooling
weld pool. Adjustable from 0 to 15
seconds.
10.6 Arc Force
When machine is in Stick MMA
mode, selecting the ARC FORCE
allows adjustment of the increase in
current that will occur when the arc
starts to short circuit, or snap out.
Adjusting this value can be useful
when using cellulose electrodes.
The amount of current is preset,
the adjustment is a % of the
preset value.
10.7 Hot start
When machine is in Stick MMA
mode, selecting HOT START
allows adjustment of the increase in
current that will occur at Arc Start
HOT START is useful for getting arc
established on a cold start.
The amount of current is preset,
the adjustment is a % of the
preset value.
11 Power On/Off Switch
In the OFF position, this switch isolates the
power source from mains power supply.
The switch is located on the rear panel.
12 Remote Control Adjustment
The output current of the machine can
be controlled remotely by On/ Off trigger
switch control and current control
adjustment, located in the torch hand
piece, or in foot control.
The Remote control adjustment will allow
minimum to 100% of the current setting on
the machine.
For example if the machine is set to 150A the
remote adjustment will adjust 10-150A.
12.1 TIG torch used for remote
control adjustment
The TIG torch will require a trigger switch
and current control potentiometer in the
hand piece.
Control plug of the TIG torch is
connected to the machine remote control
socket FIG 7.
Turn the machine on.
First the machine needs to be adjusted to
maximum desired current.
To do this the remote control knob
on the TIG torch needs to be adjusted
to maximum.
Adjust to the desired maximum current
(such as 150A) on the machine with the
control knob FIG 1 (5). The AMPs digital
display will then show 150A.
Adjust the control knob on the TIG torch,
the AMPS display will then change as the
knob is adjusted.

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5 Controls
12.2 Foot Control for remote
control adjustment
The WIA foot control (part number
AA76) has an in built trigger switch and
current control and can be used to
control the weld start and weld current.
Control plug of the TIG torch is
connected to the machine remote control
socket FIG 7.
Turn the machine on.
First the machine needs to be adjusted to
maximum desired current
Select LIFT TIG MODE to prevent HF
during setup.
Press the foot control pedal to maximum.
Adjust to the desired maximum current
(such as 150A) on the machine with the
control knob FIG 1 (5). The AMPs digital
display will then show 150A.
Release the foot control pedal and the
current to will adjust down from 150A
to 10A.
HF MODE can now be selected
if required.

Weldmatic 200i DC
Model No MC109 15
6 Installation
Connection to Electrical Mains Power
Supply
The Weldarc 200i DC is fitted with a 15 Amp
plug, recognisable by a wide earth pin.
Power supply authorities require that
equipment fitted with a 15 Amp plug shall
ONLY be connected to a 240 Volt, 15 Amp
power point. DO NOT modify the plug.
The minimum capacity of the main power
supply wiring and power outlet supplying a
welder is selected according to the Effective
Primary Current of the equipment. Refer to
Section 4.
The minimum recommended main power
supply circuit breaker ratings for the Weldarc
200i DC inverters are listed in Section 4.
The current rating of the mains cable
depends on cable size and method of
installation. Refer to AS/NZS 3008.1, Table 9.
If it becomes necessary to replace the mains
flexible supply cable, use only cable with
correct current rating. See Section 4.
If it is necessary to use an extension power
supply cable, ensure that it is rated as per
Section 4. Voltage drop which will occur
over long lengths of cable will reduce the
maximum welding current available from the
equipment.
Successful Operation
Welding equipment at maximum output
require high current during operation, then
minimum current during idle time.
Mains supply circuit breaker tripping can
sometimes occur.
Successful operation will depend on a
number of factors:
• Variation in circuit breaker thresholds.
• Ambient temperature.
• Number of previous circuit breaker
operations.
• Actual weld conditions, resulting in
higher weld currents.
• Repeated starts can result in repeated
surge currents raising circuit breaker
threshold.
Repeated Circuit breaker operation at weld
start can sometimes be overcome by using a
“D” curve circuit breaker.
To reduce nuisance tripping, a higher
rated circuit breaker can be selected, but
the supply circuit wiring capacity must be
increased to suit.
Connection to Generator
The Weldarc 200i DC can be operated from a
generator. The PFC feature will allow greater
tolerance to variable generator outputs.
However, it is not recommended that the
equipment be powered from small engine-
driven generator sets unless they have
adequate voltage regulation. Poor regulation
results in peaks of supply voltage which can
occur with some equipment of this type.
Excessive voltage peaks can damage the
circuits of the welder.
Generators used to power this equipment
must have the recommended minimum
capacity and incorporate output voltage
regulation.
Due to variation between generators by
different manufacturers, it is impossible
for WIA to validate operation from all
generators. Therefore, correct operation of
welding equipment on the generator should
be confirmed by the manufacturer, before
purchasing the generator.

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7 Basic Welding Information
Stick Welding (MMAW)
Connection for Stick Welding
It is important to select the electrode polarity
in accordance with the manufacturers
recommendations for that electrode. Most
common electrodes, including cellulose
types, are operated with the electrode at
positive polarity, as illustrated in Figure 6.
Stick Welding
Be certain that you are wearing suitable
protective clothing, gloves etc and that
you are working in a non-hazardous area.
If necessary, refer again to Section 1 - Safe
Practices in this manual.
Connect the work clamp to the work
piece. Place the desired electrode in the
electrode holder.
Turn on the power switch located on the rear
panel. Wait approximately 5 seconds as the
unit goes through its initiation sequence.
Use the Weld Mode Selection button to
select Stick Mode.
Select an appropriate welding current for
the electrode diameter by setting the knob
on the machine front panel. WIA AUSTARC
electrodes will give the best results.
Work
ClampElectrode
To strike the arc, drag the end of the
electrode along the work piece as if striking
a match. As the arc initiates, lift the electrode
slightly away, aiming to establish an arc
length of approximately 3mm.
As the electrode end is consumed, feed the
electrode into the arc in order to maintain
arc length. As a general rule, the arc should
be held as short as possible while still giving
stable burn off and good weld appearance.
An arc which is too long causes an unwieldy
flow of metal with a rough weld appearance
and reduced penetration. An arc too short
leads to a narrow weld deposit and “stuttery”
arc characteristics, and the electrode is liable
to freeze onto the work piece.
As the solidified weld deposit forms, move
the end of the electrode slowly along
the weld path, aiming to maintain a pool
of molten weld metal behind the arc.
Decreasing this rate of travel will result in a
wider weld deposit, and similarly increasing it
will narrow the weld deposit.
Always fill the crater which tends to form
at the end of a weld deposit, by pausing
momentarily before withdrawing the electrode
to break the arc. Unfilled craters are a point
of weakness, and can lead to weld cracking.
Current Range for General Purpose
Electrodes
Diameter (mm) Current (Amps)
2.0 40 -60
2.5 60 - 85
3.2 90 - 130
4.0 130 - 180
Fig 6 Connections for Stick Welding (MMAW)

Weldmatic 200i DC
Model No MC109 17
TIG Welding (GTAW)
Connection for TIG Welding
For TIG Welding, the TIG torch is connected
to the negative terminal. Figure 7 illustrates
the correct connection of the welding torch
and gas supply. Welding grade Argon is
the shielding gas most commonly used for
DC GTAW welding. The torch will require a
tungsten electrode.
Before first use of the welding torch,
allow gas to purge the torch and hoses for
1 minutes at approximately 10 litres/min. For
welding purposes, the gas flow rate should
be set in the range 5-11 litres/min.
Fig 7 Connections for TIG Welding
Electrode TIG
Thoriated Tungsten electrodes are normally
used for DC welding current.
Tungsten Electrode Preperation
The tungstens needs to be ground to a point,
the grinding should only be in the direction
of the point and should be done on a fine
grit grinding wheel. The resulting grind
pattern will produce a sharp directed arc.
Poor tip preparation will result in arc wander.
A common practice is to grind the tip such
that the length of the points is approximately
2 times the diameter. The result will be an
included angle of 30 degrees.
It is important to maintain the electrode
point for DC. If the tip accidently touches
weld pool it will become contaminated and
the arc will become erratic, and will need to
be re ground.
Tungstens containing at least 2% lanthana
will hold a point when used for DC TIG.
7 Basic Welding Information
TIG
Torch
Work
Clamp

18
Operators Manual
Trusted by the best
D
x
Fig 9 AC Advanced Preparation
x = 1.5 to 4 times diameter
Fig 10 Correct Grind Direction
Fig 11 Incorrect Grind Direction
D
30°
30° x
Fig 8 Tungsten Preparation
x = 1.5 to 4 times diameter
(2 x D = 30° included angle)
Tungsten Current Ranges
Electrode
Diameter (mm)
Gas
Cup Size
DC
Current Amps
Filler Wire
Diameter (mm)
1.0 6 15-80 1.6
1.6 6 70-150 1.6-2.4
2.4 8 150-250 2.4-3.2
Safety Consideration Thoritated
Tungsten.
Thoriated Tungsten contains the element
Thorium (Th). Thorium is a radioactive
element which mainly emits alpha
particles. Alpha particles cannot penetrate
skin, or clothing, but can be a harmful
carcinogen if released inside the digestive
tract, or lungs.
There is almost no release of radioactive
material during arcing.
There is no significant hazard in handling
and storage. The Thoria is inside the
tungsten electrode, it is enclosed in a
tungsten matrix and so there is little
radiation emitted externally.
The greatest risk of exposure is during
the grinding of the thoriated tungsten
electrodes. Care needs to be taken, to
control the dust. A dust mask should be
worn, and grinder area clean up should
be done with a vacuum cleaner.