Stealth 9000H Operator's Manual

Part No. 9000H

DIGI-MIG 200

OPERATOR’S

MANUAL

STEALTH DIGI-MIG 200

IMPORTANT

Read this Owner’s Manual completely before attempting to use this equipment.

Save this manual and keep it handy for quick reference. Pay particular attention
to the safety instructions provided for your protection. Contact your distributor if
you do not fully understand this manual.

CONTENTS

1. SAFETY 4

1.1 SIGNAL EXPLANATION 4

1.2 ARC WELDING DAMAGE 4

1.3 ELECTRIC AND MAGNETIC FIELDS INFORMATION 7

2. SUMMARY 8

2.1 BRIEF INTRODUCTION 8

2.2 FEATURES 8

2.3 WORKING PRINCIPLE 9

2.4 VOLT-AMPERE CHARACTERISTIC 9

3. INSTALLATION AND ADJUSTMENT 11

3.1 PARAMETERS 11

3.2 DUTY CYCLE AND OVER-HEATING 12

3.3 EQUIPMENT CONNECTION 12

3.4 OPERATION STEPS 13

3.5 MIG GUN MECHANISM MAINTENANCE 14

3.6 MIG GUN OPERATION 15

4. OPERATION 16

4.1 LAYOUT OF FRONT AND REAR PANEL 16

4.2 MIG WELDING OPERATION 18

4.3 TIG WELDING OPERATION 19

4.4 MMA WELDING OPERATION 20

4.5 WELDING PARAMETERS 20

4.6 OPERATION ENVIRONMENT 21

4.7 OPERATION NOTICES 21

5. MAINTENANCE & TROUBLESHOOTING 22

5.1 MAINTENANCE 24

5.2 TROUBLESHOOTING 23

5.3 MAIN ELECTRICAL DIAGRAM 25

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STEALTH DIGI-MIG 200

1. SAFETY

1.1 Signal Explanation

• The above icons mean Warning! Notice! Running and thermal parts or receiving an
electric shock may harm you or others. The following precautions apply as a guide
to working safely.

1.2 Arc Welding Damage

• The following icons explanations are to prevent accidents to you or others during
the welding process.

• Only experienced personell can install, operate, maintain and repair the equipment.

• During the operation make sure those around you are properly protected.

• After turning off the machine power, please maintain and examine the equipment
according to 5 due to DC voltage existing in the electrolytic capacitors.

ELECTRIC SHOCK CAN KILL

• Never touch live electrical parts.

• Wear dry, hole-free gloves and clothes to insulate yourself.

• Insulate yourself from work and ground using dry insulation. Make certain the
insulation is large enough to cover your full area of physical contact with work and
ground.

• Take care when using the equipment in a confined space, on uneven surfaces and
in damp conditions.

• Shut down the incoming electrical supply prior to the equipment’s installation.

• Ensure the equipment is installed correctly and the work or metal is earthed
according to the operation manual.

• The electrode and work (or ground) circuits are ‘hot’ when the machine is on. Do not
touch these electrically ‘hot’ parts with your bare skin or wet clothing. Wear dry,
hole-free gloves to insulate hands.

• In semiautomatic or automatic wire welding, the electrode, electrode reel, welding
head, nozzle or semiautomatic welding gun are also electrically ‘hot’.

• Always ensure the work cable makes a good electrical connection and is as close as
possible to the metal being welded.

• Ensure the electrode holder, work clamp, welding cable and welding machine are
in good, safe operating condition. Replace any damaged insulation.

• Never dip the electrode in water for cooling.

• Never simultaneously touch electrically ‘hot’ parts of electrode holders connected to
two machines as voltage between the two can be the total of the open circuit voltage
of both welders.

• When working above floor level, use a safety belt to protect yourself from a fall
should you receive an electric shock.

FUMES AND GASES CAN BE DANGEROUS

• Welding may produce fumes and gases hazardous to health. Avoid breathing these
fumes and gases.

SAFETY

§1 SAFETY

§1.1 Signal Explanation

SAFETY

§1 SAFETY

§1.1 Signal Explanation

 The above signals mean warning! Notice! Running parts and getting an electric shock or thermal parts

will take damage for your body or others. The corresponding notices are as follows. It is quite a safe

operation after taking several necessary protection measures.

§1.2 Arc Welding Damage

 The following signals and word explanations are to some damages for your body or others happening

on the welding operation. While seeing these, please remind of yourself or others to be dangerous.

 Only ones who are trained professionally can install, debug, operate, maintain and repair the

equipment.

 During the operation, non-concerned people should be lift, especially for children.

 After shut off the machine power, please maintain and examine the equipment according to §5

because of the DC voltage existing in the electrolytic capacitors.

ELECTRIC SHOCK CAN KILL.

SAFETY

semiautomatic welding gun are also electrically “hot”.

 Always be sure the work cable makes a good electrical connection with the metal being welded. The

connection should be as close as possible to the area being welded.

Maintain the electrode holder, work clamp, welding cable and welding machine in good, safe

operating condition. Replace damaged insulation.

 Never dip the electrode in water for cooling.

 Never simultaneously touch electrically “hot” parts of electrode holders connected to two welders

because voltage between the two can be the total of the open circuit voltage of both welders.

 When working above floor level, use a safety belt to protect yourself from a fall should you get a

shock.

FUMES AND GASES CAN BE DANGEROUS.

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• When welding, keep your head out of fumes. Use enough ventilation and/or exhaust
at the arc to keep fumes and gases away from the breathing zone. When welding
with electrodes which require special ventilation such as stainless or hard facing or
lead or cadmium plated steel and other metals or coatings which produce highly
toxic fumes, keep exposure as low as possible and below Threshold Limit Values
using local exhaust or mechanical ventilation. In confined spaces or in some
circumstances, outdoors, a respirator may be required. Additional precautions are
also required when welding on galvanized steel.

• Do not weld in locations near chlorinated hydrocarbon vapours coming from
degreasing, cleaning or spraying operations. The heat and rays of the arc can react
with solvent vapours to form phosgene – a highly toxic gas – and other irritating
products.

• Shielding gases used for arc welding can displace air and cause injury or death.
Always use enough ventilation, especially in confined areas, to ensure breathing air
is safe.

• Read and understand the manufacturer’s instructions for this equipment and the
consumables to be used, including the material safety data sheet and follow your
employer’s safety practices.

ARC RAYS CAN BURN

• Use a shield with the correct filter and cover plates to protect your eyes from sparks
and the rays of the arc when welding or observing open arc welding.

• Use suitable clothing made from durable flame-resistant material to protect your
skin and that of your helpers from the arc rays.

• Protect nearby personnel with suitable, non-flammable screening and/or warn them
to avert their eyes from the arc rays or expose themselves to hot spatter or metal.

SELF-PROTECTION

• Keep all equipment safety guards, covers and devices in position and in good repair.
Keep hands, hair, clothing and tools away from V-belts, gears, fans and all other
moving parts when starting, operating or repairing equipment.

• Do not put your hands near the engine fan. Do not attempt to override the governor
or idler by pushing on the throttle control rods while the engine is running.

DO NOT add fuel near an open flame welding arc or when the
engine is running. Stop the machine and allow it to cool before refuelling to prevent
spilled fuel from vapourising on contact with hot engine parts and igniting. Do not
spill fuel when filling tank. If fuel is spilled, wipe it up and do not start engine until
fumes have been eliminated.

WELDING SPARKS can cause fire or explosion

• Remove fire hazards from the welding area. If this is not possible, cover them to
prevent the welding sparks from starting a fire. Remember that welding sparks and
hot materials from welding can easily go through small cracks and openings to

SAFETY

connection should be as close as possible to the area being welded.

operating condition. Replace damaged insulation.

because voltage between the two can be the total of the open circuit voltage of both welders.

shock.

FUMES AND GASES CAN BE DANGEROUS.

ARC RAYS CAN BURN.

SAFETY

arc when welding or observing open arc welding.

 Use suitable clothing made from durable flame-resistant material to protect your skin and that of your

helpers from the arc rays.

 Protect other nearby personnel with suitable, non-flammable screening and /or warn them not to

watch the arc nor expose themselves to the arc rays or to hot spatter or metal.

SELF-PROTECTION

 Keep all equipment safety guards, covers and devices in position and in good repair. Keep hands, hair,

clothing and tools away from V-belts, gears, fans and all other moving parts when starting, operating or

repairing equipment.

 Do not put your hands near the engine fan. Do not attempt to override the governor or idler by

pushing on the throttle control rods while the engine is running.

DO NOT adds the fuel near an open flame welding arc or when the engine is

SAFETY

arc when welding or observing open arc welding.

 Use suitable clothing made from durable flame-resistant material to protect your skin and that of your

helpers from the arc rays.

 Protect other nearby personnel with suitable, non-flammable screening and /or warn them not to

watch the arc nor expose themselves to the arc rays or to hot spatter or metal.

SELF-PROTECTION

 Keep all equipment safety guards, covers and devices in position and in good repair. Keep hands, hair,

clothing and tools away from V-belts, gears, fans and all other moving parts when starting, operating or

repairing equipment.

 Do not put your hands near the engine fan. Do not attempt to override the governor or idler by

pushing on the throttle control rods while the engine is running.

DO NOT adds the fuel near an open flame welding arc or when the engine is

running. Stop the engine and allow it to cool before refueling to prevent spilled fuel from vaporizing on

contact with hot engine parts and igniting. Do not spill fuel when filling tank. If fuel is spilled, wipe it

up and do not start engine until fumes have been eliminated.

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adjacent areas. Avoid welding near hydraulic lines. Have a fire extinguisher readily
available.

• Where compressed gases are to be used at the job site, special precautions should
be taken to prevent a hazardous situation.

• When not welding, make certain no part of the electrode circuit is touching the work
or ground. Accidental contact can cause overheating and create a fire hazard.

• Do not heat, cut or weld tanks, drums or containers until the proper steps have been
taken to ensure that any flammable or toxic vapours have been eliminated from
within. They can cause an explosion even though they have been ‘cleaned’.

• Vent hollow castings or containers before heating, cutting or welding. They may
ignite.

• Sparks and spatter are thrown from the welding arc. Wear oil free protective
garments such as leather gloves, heavy shirt, cuff less trousers, protective shoes and
a cap over your hair. Wear ear plugs when welding out of position or in confined
space. Always wear safety glasses with side shields when in a welding area.

• Connect the work cable to the work as close to the welding area as practical. Keep
work cables connected to the building framework or other locations away from the
welding area.

Rotating parts may be dangerous

• Use only compressed gas cylinders containing the correct shielding gas for the
process used and properly operating regulators designed for the gas and pressure
used. All hoses, fittings, etc. should be suitable for the application and maintained
in good condition.

• Always keep cylinders in an upright position securely chained to an undercarriage or
fixed support.

• Cylinders should be located:
– Away from areas where they may be struck or subjected to physical damage.
– A safe distance from arc welding or cutting operations and any other source of
heat, sparks, or flame.

• Never allow the electrode, electrode holder or any other electrically ‘hot’ parts to
touch a cylinder.

• Keep your head and face away from the cylinder valve outlet when opening the
cylinder valve.

• Valve protection caps should always be in place and hand tight except when the
cylinder is in use or connected for use.

SAFETY

an explosion even though they have been “cleaned”.

 Vent hollow castings or containers before heating, cutting or welding. They may explode.

 Sparks and spatter are thrown from the welding arc. Wear oil free protective garments such as leather

gloves, heavy shirt, cuff less trousers, high shoes and a cap over your hair. Wear ear plugs when

welding out of position or in confined places. Always wear safety glasses with side shields when in a

welding area.

 Connect the work cable to the work as close to the welding area as practical. Work cables connected

to the building framework or other locations away from the welding area increase the possibility of the

welding current passing through lifting chains, crane cables or other alternate circuits. This can create

fire hazards or overheat lifting chains or cables until they fail.

Rotating parts may be dangerous.

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1.3 Electric and Magnetic Fields

• Electric current flowing through any conductor causes localised Electric and
Magnetic Fields (EMF). The discussions of the effect of EMF is ongoing globally.
Up to now, there is no material evidence that EMF has any adverse effects on
health.
Minimise exposure to EMF as far as possible by applying the following procedures:
– Route the electrode and work cables together. Secure them with tape when
possible.
– All cables should be stored away from the operator.
– Never coil the power cable around your body.
– Make sure welding machine and power cable are far enough away from the
operator according to the working environment.
– Connect the work cable to the workpiece as close as possible to the area being
welded.
– Personnel fitted with a heart-pacemaker should keep their distance from the
welding area.

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2 SUMMARY

2.1 Brief Introduction

The Digi-Mig 200 arc welding machine adopts the latest Pulse Width Modulation (PWM)
technology and Insulated Gate Bipolar Transistor (IGBT) power module, which can
change work to medium frequency to create a lightweight medium welding machine.
This arc welding machine uses mixed gases Argon/CO2 as shielded gas for MIG/MAG
welding. Pure argon is required for TIG welding.

The Digi-Mig 200 arc welding machine has automatic protection functions with
intelligent to over-voltage, over-current and over-heat. If any one of the above problems
occurs, the alarm lamp on the front panel lights and the output current is automatically
shut off.

2.2 Features

1. Digital control system – real-time display the welding parameters

2. High performance multifunction power source (MMA/MIG/MAG)

3. Waveform control – stable welding arc

4. IGBT technology – low power dissipation

5. Rated duty circle is 40% (40º)

6. Synergic control of the welding current and voltage

The Digi-Mig 200 arc welding machine is suitable for all welding positions for
various metals: stainless steel; carbon steel; alloyed steel; copper; titanium; etc,
with various applications including: pipe installation; mould repair; petrochemical;
architectural decoration; car repair; bicycle; handicraft and DIY.

MAG – Metal Active Gas welding

MIG – Metal Inert Gas welding

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2.3 Working Principle

The working principle of the Digi-Mig 200 welding machines is shown as follows:
Single-phase 220V work frequency AC is rectified into DC 350V, it is then converted to
medium frequency AC (about 40KHz) by the inverter device (IGBT). The reducing of
voltage using the medium transformer (the main transformer) whilst rectifying using
the medium frequency rectifier (fast recovery diodes) is outputted by inductance
filtering.

The circuit adopts current feedback control technology to ensure current output is
stable when MMA or TIG welding. It also adopts voltage feedback control technology to
ensure voltage output is stable when MIG welding. The welding current parameter can
be adjusted continuously and infinitely to meet with the requirements of all welding
processes..

2.4 Volt-Ampere Characteristic

The Digi-Mig 200 welding machine has an excellent volt-ampere characteristic, shown
in the graph below. The relation between the conventional rated loading voltage U2 and
the conventional welding current I2 is as follows:

U2=14+0.05I2(V).

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OVERVIEW

§2.2 Working Principle

The working principle of MIG SERIES arc welding machine is shown as the following figure.

Single-phase 220V work frequency AC is rectified into DC（350V）, then is converted to medium

frequency AC (about 40KHz) by inverter device (IGBT), after reducing voltage by medium

transformer (the main transformer) and rectifying by medium frequency rectifier (fast recovery

diodes), and is outputted by inductance filtering. The circuit adopts current feedback control

technology to insure current output stably when MMA or TIG. And adopts voltage feedback

control technology to insure voltage output stably when MIG. Meanwhile, the welding current

parameter can be adjusted continuously and infinitely to meet with the requirements of welding

craft.

Rectifier Inverter Transformer Rectifier Hall

Current

Feedback

control

Single-phase AC

DC

AC DC

220V 50Hz

AC DC

Welding current

regulate

(Wire feed speed)

Wire feeder

motor

PWM signal

CPU control

Voltage

Feedback

control

Current sensor

OVERVIEW

44

14

0 600

I

o

（A）

U

o

（V）

Working point

Volt-ampere characteristic

The relation between the rated loading

voltage and welding current

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2.5 Principles of welding

OVERVIEW

44

14

0 600

I

o

（A）

U

o

（V）

Working point

Volt-ampere characteristic

The relation between the rated loading

voltage and welding current

§2.4Principles of welding

1~220/230/240±10%

50/60

MIG 42 MMA 44 TIG 31

MIG 5.9 MMA 5.3 TIG 4.3

DIGI-MIG 200

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3 INSTALLATION AND ADJUSTMENT

3.1 Parameters

Input Voltage (V)

IP23

H

0.75

AF

85

511 × 213 × 400

15

13.5-27

63

40-200 (MIG/MAG)
10-200 (MMA/TIG)

40% 200A
60% 165A

100% 130A

Fe: 0.6, 0.8, 0.9, 1.0

S/S: 0.8, 0.9, 1.0

Flux-Cored: 0.6, 0.8, 0.9, 1.0

Frequency (Hz)

Input Current (A)

Input Power (Kw)

Welding Voltage Range (V)

Welding Current (A)

No Load Voltage (V)

Protection Class

Power Factor

Efficiency (%)

Duty Cycle (40ºC)

Diameter (mm)

Insulation Class

Cooling

Net Weight (Kg)

Dimensions (mm) L × W × H

3.2 Duty Cycle and Over-heating

The letter ‘X’ stands for duty cycle,
which is defined as the proportion
of the time that a machine can work
continuously within a certain time (10
minutes). The rated duty cycle means
the proportion of the time that a
machine can work continuously within
10 minutes when it outputs the rated
welding current.

The relation between the duty cycle ‘X’
and the output welding current ‘I’ is
shown as the figure on the right.

If the transformer over-heats, the heat relay inside will open and send an instruction to
the circuit board, cut AC relay and the output welding current. The over-heat pilot
lamp in the front panel is lit.

At this point, the machine should be turned off for 15 minutes to cool the fan. When
operating the machine again, the welding output current or the duty cycle should be
reduced.

3.3 Equipment Connection

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3.4 Operation steps

3.4.1 Connect the power source input cable with the output air switch port.

3.4.2 Connect the wire feeder cable plug to the positive output of welding machine.

3.4.3 Connect the wire feeder control cable plug to the aero socket on the front board.

3.4.4 Connect the negative pole to the work piece (base metal).

3.4.5 Connect the gas cylinder output pipe to the gas valve input joint on the wire
feeder and clamp it.

3.4.6 Insert the torch joint into the wire feeder unit output and keep the wire aimed at
the wire feeder mouth.

NOTE The Torch euro connector should be pushed in firmly and rotated until it locks
into position tightly. Ensure the torch connection pins are lined up with the
brass gun housing on the machine panel.

3.4.7 Connect the torch shielded gas pipe with the front panel output on the wire
feeder.

3.4.8 Connect the torch control cable pin with the two-lead aero socket on the wire
feeder.

3.4.9 Ensure the wire diameter corresponds to the wire wheel and torch tip and press
the wire with the handle.

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3.5 MIG gun mechanism maintenance

3.5.1 Breakdown of parts

3.5.2 Parts list

No. Description Qty.

1 Tip D.12 14-15AK 1
2 Electric nozzle 0.8/M6x25 1
3 15AK Goose gun neck (hexangular adapter and plastic adapter) 1

3.1 15AK Goose gun 1
4 Hexangular adapter 1
5 Plastic adapter 1
6 MIG blue handle 1
7 Torch Switch 21.8mm 1
8 Screw D.3x10 3
9 Handle locking ring 1
10 Cable fixing joint 15AK 1
11 Coaxial cable team /16mmq/3m 1
12 Cable thimble 12-16-25 MMQ 1
13 CO2 Euro-rear thimble 1
14 Screw M4x6 UNI 6107 1
15 Torch locknut /plastic screw thread 1
16 Euro-main socket/flexibility pin 1
17 Feeding pipe locknut 1
18 Insulating feed pipe 0.6-0.8 3m, blue 1
19 Spanner for the electric nozzle 1

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OPERATION

§3.4 Maintenance of MIG Gun mechanism

§3.4.1 Dissection graphics for the MIG GUN

1

2

3

4

7

11

1

2

1

3

1

4

1

5

1

6

1

7

1

8

1

9

10

95 6

8

3.1

3.6 Mig gun operation

3.6.1 Service the wire feed mechanism every time the reel is changed:

– Check the wear of the feed roll groove and change the feed roll as necessary.

– Clean the welding gun wire guide with compressed air.

3.6.2 Cleaning the wire guide

Remove all metal dust from the feed rollers which may be caused by over
tightening the top tension arm. This will prevent dust from entering the wire
guide causing potential wire feed problems. If the wire guide is not cleaned it
gradually clogs up and causes wire feed malfunctions. Clean the wire guide in
the following manner:

– Remove the welding gun’s gas nozzle, contact tip and contact tip’s adapter.

– With a pneumatic pistol, blow compressed air through the wire guide.

– Blow the wire feed mechanism and reel housing clean with compressed air.

– Reattach the welding gun’s parts. Tighten the contact tip and contact tip’s
adapter.

3.6.3 Changing the wire guide

If the wire guide is too worn or totally clogged, replace according to the
following instructions:

– Open the mounting nut of the wire guide to expose the end of the wire guide.

– Straighten the welding gun’s cable and withdraw the wire guide from the gun.

– Push a new wire guide in to the gun up to the contact tip’s adapter until it
reaches an O-ring at the machine-end of the guide.

– Tighten the wire guide in place with the mounting nut.

– Cut the wire guide 2mm from the mounting nut and file the sharp edges of
the cut round.

– Reattach the gun in place and tighten the parts.

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16

4 OPERATION

4.1 Layout of the front and rear panel

OPERATION

§4 Operation

§4.1 Layout for the front and rear panel

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1. Choose welding mode key:
On TIG or MIG, press the key to choose 2T or 4T welding mode.

2. Choose welding method key:
Press the key to choose three functions – MMA/TIG/MIG.

3. Welding current knob:
Set the welding current.

4. Current display:
Displays when machine is working. Set current display before welding. Unit A.

5. Current LED:
When the current LED is lit, it displays the actual output welding current (MIG).

6. Wire speed LED:
Use current setting knob to set the wire speed when LED is lit (MIG).

7. Voltage display:
Displays when machine is working Set voltage display to MIG mode before welding.
Unit V.

8. Welding voltage / Down slope / Arc force knob:
On MIG, when the program voltage cannot match the welding current, the knob
can adjust voltage. On TIG, the knob can adjust the current down time. On MMA,
the knob can adjust the force current.

9. Power LED:
Power LED is lit when the machine is turned on.

10. Alarm LED:
When the welder is over voltage, less voltage, over current or over heated, the
alarm pilot lamp will light.

11. Wave control knob:
Controls arc characteristics determines the rate at which the amperage rises when
a short circuit is produced.

12. TIG GAS connect.

13. MIG GUN connect.

14. Output cathode:
When in MIG mode, this polarity must connect to the work piece

15. TIG gun control connecter.

16. Output anode:
When in TIG mode, this polarity must connect to the work piece.

17. Remote switch.

18. Spool Gun switch.

19. Burnback knob.

20. Slow feed knob.

21. Manual wire switch and air check switch: UP for manual wire and DOWN for air check.

22. Post flow knob.

23 Pre-flow knob.

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4.2 MIG welding operation

4.2.1 Shielding gas material selection:

• Ferrous – 80% Ar + 20% CO

2

• Stainless Steel – 98% Ar + 2% O2

• Aluminium – 100% Ar

4.2.2 Welding state choice:

• Press the Weld key and select MIG mode – the LED is lit:

• Turn off Spool Gun switch (down)

• Manual Wire switch and Air Check switch, Burnback adjust, Slow Feed adjust,
Post Flow adjust, Pre-Flow adjust:

4.2.3 Press the welding mode key, select 2T or 4T:

4.2.4 Turn on Spool Gun switch (up)

OPERATION

OPERATION

- 17 -

adjust, Pre-flow knob adjust；

OPERATION

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4.2.5 Welding parameter adjustment

• For different wire diameters, the minimum welding current available will vary

• Adjust Current knob – the corresponding welding voltage is changed
automatically

• When the programmable welding voltage is not suitable for the operator – the
voltage can be finely adjusted by the knob

• The arc characteristics can be adjusted using the wave control knob

4.3 TIG welding operation

4.3.1 Press the welding operation key, select TIG mode – LED is lit

4.3.2 Press the welding mode key, select 2T or 4T

4.3.3 Adjust the current knob to control the welding current

4.3.4 Adjust the down slope knob to control the welding current descend time

OPERATION

3)Press the welding mode key, choose 2T or 4T；

4)Spool Gun Switch turn on(up):

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4.4 MMA welding operation

4.4.1 Press the weld key, choose MMA mode – LED is lit

4.4.2 Adjust the current knob to control the welding current

4.4.3 Adjust the welding arc force knob to control the arc force current

NOTE The current (amps) is set prior to welding, the current displayed when welding
will vary slightly as will the welding voltage displayed depending on the arc
length maintained.

4.5 Welding parameters

Wire diameter (mm) Welding current (A) Plate thickness (mm)

0.6 25-110 1.0-1.6

0.8 35-160(200) 1.0-2.3

0.9 45-160(200) 1.0-2.3

1.0 45-160(200) 1.2-6

OPERATION

4. Adjust the down slope knob to control the welding current descend time.

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4.6 Operation Environment

• Height above sea level below 1000m

• Operation temperature range: –10ºC~+40ºC

• Relative humidity below 90% (20ºC)

• Preferably site the machine above floor level with the maximum angle not exceeding

15º.

• Protect the machine against heavy rain, hot environments and direct sunshine

• The content of dust, acid, corrosive gas in the surrounding air or substance should

not exceed normal standards

• Take care that there is sufficient ventilation during welding and there is at least
30cm free distance between the machine and wall

4.7 Operation Notices

• Read all notes carefully before attempting to use this equipment

• Connect the ground wire with the machine directly, and refer to 3.5

• If the power switch is accidentally closed, no-load voltage may be exported. Do not

touch the output electrode with any part of your body

• Ensure that the input is single-phase: 50/60Hz, 220/230/240V±10%

• Before operation ensure no other presonnnel is present without proper eye
protection

• Ensure good ventilation of the machine to improve duty ratio.

• Turn off the engine when the operation finished to economize energy source.

• If the power switch shuts off accidentally, do not restart until the problem is

resolved

• In case of any unresolved problems, contact your authorised dealer

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5 MAINTENANCE AND TROUBLESHOOTING

5.1 Maintenance

In order to guarantee that an arc welding machine works efficiently and safely, it must

be maintained regularly. Read and understand the maintenance methods and regularly
carry out safety checks. Make any repairs as required in order to extend the service life
of the welding machine. Maintenance items are detailed in the following tables.

• Warning: Safely maintain the machine by shutting off the power supply and waiting
for 5 minutes until the capacity voltage drops to a safe voltage of 36V.

DATE MAINTENANCE CHECKS

Daily Observe whether panel knob and switch in the front and at the back of arc
examination welding machine are flexible and placed correctly. If the knob has not been
correctly installed, please correct. If this is not possible, replace immediately,

If the switch is not flexible or it cannot be correctly installed, please replace
immediately. Contact your distributor if there are no parts to hand.

After switching on power, watch and listen to check the arc welding machine is
not shaking, whistling or giving out an unusual odour. If so, investigate and
eliminate. If any problem persists please contact your distributor.

Observe the LED is working correctly. If the number is not displayed, replace the
LED. If it still does not work, maintain or replace the display PCB.

Observe whether the min/max value on LED accords with the set value. If there
is any difference and it has affected the normal welding process, adjust
accordingly.

Check fan for damage and correct rotation. If damaged, change immediately.
If the fan does not rotate after the arc welding machine is overheated, check
the blade is not obstructed. If the fan still does not rotate after eliminating the
above, push the blade in the direction the fan rotates. If the fan rotates
normally, the start capacity should be replaced. If not, change the fan.

Check whether the fast connector is loose or overheated. If so, it should be
fastened or changed.

Check the current output cable is not damaged. If so, it should be securely
insulated or replaced.

S/N PROBLEM REASON SOLUTION

Breaker damaged Change breaker
The breaker is closed but the
1 power light is not lit

Fuse damaged Change fuse

Check power input Try another power input

2

After welding the machine is

Fan damaged Change fan

over heated and fan does not
work

Cable is loose Tighten cable

No gas in the gas cylinder Change gas cylinder

Gas pipe leaks gas Change gas pipe

3 Electromagnetic valve damaged Change valve

Control switch damaged Change switch

Control circuit board damaged Change circuit board

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DATE MAINTENANCE CHECKS

Monthly Use dry compressed air to clear the inside of arc welding machine. Pay
examination particular attention to clear any dust on radiator, main voltage transformer,
inductance, IGBT module, the fast recover diode and PCB, etc.

Check the arc welding machine bolt. If loose, tighten. Replace if worn. Scrape
off any rust to ensure it works efficiently.

Quarterly Check the actual current accords with the displaying value. If not, they should
examination be reconfigured. The actual current value can be measured by the adjusted
plier-type ampere meter.

Annual Measure the insulating impedance among the main circuit, PCB and case.
examination If it is below 1MΩ, insulation may be damaged and should be repaired or
replaced.

5.2 Troubleshooting

• Before arc welding machines are dispatched from the factory, they have already been
carefully checked. Do not allow anyone unauthorised to make any alterations to the
equipment.

• Maintenance work must be carefully undertaken. If any wire becomes loose or
misplaced, it may be a potential danger to the user.

• Only authorised professional maintenance personnel should overhaul the machine.

• Ensure the arc welding machine’s power is switched off before the mains power to

the machine is switched on.

• If any problems persist contact an authorised professional or your supplier.

Gun switch
pressed but
no shielded
gas output

No output
gas when
tested

Gas output
when tested

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S/N PROBLEM REASON SOLUTION

Motor damaged Check and change

Control circuit board damaged Change circuit board

Press wheel is loose or weld

Re-tighten

wire skids

4 Wheel does not fit with weld

Change wheel

wire diameter

Wire reel damaged Change wire reel

Wire feed pipe jammed Repair or change

Tip jammed due to splash Repair or change

Output cable is badly

Tighten or replace

5 connected or loose

Control circuit board damaged Change circuit board

6

Welding stops and alarm light

Check over-voltage, over-

is on

Machine is self-protected current, over-temperature,

lower-voltage and resolve

Welding current runs away

Potentiometer is damaged Check and replace

7

and cannot be controlled

Control circuit is damaged Check the circuit and replace

8 The crater current cannot be

PCB is damaged Check and replace

adjusted

9 No post-gas PCB is damaged Check and replace

Wire reel
works

Wire-feeder
does not
work

Wire reel does
not work

No striking arc and no
voltage output

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5.3 Main Electrical Diagram

MAINTENANCE AND TROUBLESHOOTING

§5.3Electrical schematic drawing

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STEALTH DIGI-MIG 200

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