Top Gun TIG 320 AC/DC User manual

.
2014．06
TIG 320 AC/DC
INVERTER AC/DC PULSED TIG WELDER
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 we have provided for your protection. Contact your
distributor if you do not fully understand this manual.
OPERATOR’S MANUAL

II
CONTENT
§1 SAFETY .............................................................................................................................................1
§1.1 SIGNAL EXPLANATION...................................................................................................................1
§1.2ARC WELDING DAMAGE ...............................................................................................................1
§1.3THE KNOWLEDGE OF ELECTRIC AND MAGNETIC FIELDS ...............................................................5
§2 SUMMARY........................................................................................................................................6
§2.1 BRIEF INTRODUCTION...................................................................................................................6
§2.2 MODULE EXPLANATION ................................................................................................................8
§2.3WORKING PRINCIPLE.....................................................................................................................8
§2.4VOLT-AMPERE CHARACTERISTIC ..................................................................................................9
§3 INSTALLATION AND ADJUSTMENT........................................................................................10
§3.1 PARAMETERS...............................................................................................................................10
3.2 DUTY CYCLE &OVER HEAT........................................................................................................... 11
§3.3 MOVEMENTAND PLACEMENT...................................................................................................... 11
§3.4 POWER SUPPLY INPUT CONNECTION.............................................................................................12
§3.5 POLARITY CONNECTION（MMA）............................................................................................12
§3.6ASSEMBLING THE EQUIPMENT (TIG) ...........................................................................................13
§4 OPERATION ...................................................................................................................................14
§4.1 LAYOUT FOR THE PANEL ..............................................................................................................14
§4.2 CONTROL PANEL..........................................................................................................................15
§4.3.1 PEDAL SWITCH CONTROL .......................................................................................................19
§4.3.2 GUN SWITCH CONTROL CURRENT ...........................................................................................19
§4.4ARGON ARC WELDING OPERATION .............................................................................................20
§4.4.1 TIG WELDING
（ 4TOPERATION ） ......................................................................................20
§4.4.2 TIG WELDING (2T OPERATION)..............................................................................................21
§4.5WELDING PARAMETERS...............................................................................................................23
§4.5.1 JOINT FORMS IN TIG/MMA ...................................................................................................23
§4.5.2 THE EXPLANATION OF WELDING QUALITY ...............................................................................23
§4.5.3 TIG PARAMETERS MATCHING.................................................................................................23
§4.6OPERATION ENVIRONMENT .........................................................................................................26
§4.7OPERATION NOTICES...................................................................................................................27
§5 MAINTENANCE & TROUBLESHOOTING..............................................................................28
§5.1 MAINTENANCE............................................................................................................................28
§5.2TROUBLESHOOTING..................................................................................................................... 29
§5.3ELECTRICALPRINCIPLE DRAWING ...............................................................................................32

SAFETY
1
§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.
Never touch 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 carefully when using the equipment in small place, falling-off and wet circumstance.
Never close the machine power before installation and adjustment.
Ensure to install the equipment correctly and ground the work or metal to be welded to a good
electrical (earth) ground according to the operation manual.
The electrode and work (or ground) circuits are electrically “hot” when the welder is on. Do not touch
these “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

SAFETY
2
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.
Welding may produce fumes and gases hazardous to health. Avoid breathing these fumes and gases.
When welding, keep your head out of the fume. 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 on 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 vapors coming from degreasing, cleaning or
spraying operations. The heat and rays of the arc can react with solvent vapors 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 insure 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 proper filter and cover plates to protect your eyes from sparks and the rays of the

SAFETY
3
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.
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 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 used to prevent
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 insure
that such procedures will not cause flammable or toxic vapors from substances inside. They can cause

SAFETY
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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.
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
5
§1.3 The knowledge of Electric and Magnetic Fields
Electric current flowing through any conductor causes localized Electric and Magnetic Fields
(EMF). The discuss on the effect of EMF is ongoing all the world. Up to now, no material evidences
show that EMF may have effects on health. However, the research on damage of EMF is still ongoing.
Before any conclusion, we should minimize exposure to EMF as few as possible.
In order to minimize EMF, we should use the following procedures:
Route the electrode and work cables together – Secure them with tape when possible.
All cables should be put away and far from the operator.
Never coil the power cable around your body.
Make sure welding machine and power cable to be far away from the operator as far as possible
according to the actual circumstance.
Connect the work cable to the workpiece as close as possible to the area being welded.
The people with heart-pacemaker should be away from the welding area.

SUMMARY
6
§2 SUMMARY
§ 2.1 Brief Introduction
TIG 320 400 AC/DC welding machine adopts the latest pulse width modulation (PWM)
technology and insulated gate bipolar transistor (IGBT) power module, which can change work
frequency to medium frequency so as to replace the traditional hulking work frequency transformer with
the cabinet medium frequency transformer. Thus, it is characterized with portable, small size, light
weight, low consumption and etc.
The parameters of TIG 320 400 AC/DC on the front panel all can be adjusted continuously and
steplessly, such as start current, crater arc current, welding current, base current, duty ratio, upslope time,
downslope time, pre-gas, post-gas, pulse frequency, AC frequency, balance, hot start, arc force and arc
length etc. When welding, it takes high frequency and high voltage for arc igniting to ensure the success
ratio of igniting arc.
TIG 320 400AC/DC Characteristic
s：
MCU control system, responds immediately to any changes.
High frequency and high voltage for arc igniting to ensure the success ratio of igniting arc,
the reverse polarity ignition ensures good ignition behavior in TIG-AC welding.
Avoid AC arc-break with special means, even if arc-break occurs the HF will keep the arc
stable.
Pedal control the welding current.
TIG/DC operation,If the tungesten electrode touches the workpiece when welding, the
current will drop to short-circuit current to protect tungsten.
Intelligent protection: over-voltage, over-current, over-heat, when the problems listed before
occurred, the alarm lamp on the front panel will be on and the output current will be cut off.
It can self-protect and prolong the using life.
Double purposes : AC inverter TIG/MMA and DC inverter TIG/MMA, Excellent
performance on Al-alloy
、
carbon steel
、
stainless steel
、
titanium.
According to choosing the front panel functions, the following six welding ways can be realized.
DC MMA
DC TIG

SUMMARY
7
DC Pulse TIG
AC MMA
AC TIG
AC Pulse TIG
1.For DC MMA, polarity connection can be chosen according to different electrodes，please refer
to §3.5；
2.For AC MMA, magnetic flow caused by invariable DC polarity can be avoided；
3.For DC TIG, DCEP is used normally (workpiece connected to positive polarity, while torch
connected to negative polarity). This connection has many characters, such as stable welding arc,
low tungsten pole loss, more welding current, narrow and deep weld;
4.For AC TIG (rectangle wave), arc is more stable than Sine AC TIG. At the same time, you can
not only obtain the max penetration and the min tungsten pole loss, but also obtain better clearance
effect.
5.DC Pulsed TIG has the following characters: 1) Pulse heating. Metal in Molten pool has short
time on high temperature status and freezes quickly, which can reduce the possibility to produce hot
crack of the materials with thermal sensitivity. 2) The workpiece gets little heat. Arc energy is
focused. Be suitable for thin sheet and super thin sheet welding. 3) Exactly control heat input and
the size of the molten pool. The depth of penetration is even. Be suitable for welding by one side
and forming by two sides and all position welding for pipe. 4) High frequency arc can make metal
for microlite fabric, eliminate blowhole and improve the mechanical performance of the joint. 5)
High frequency arc is suitable for high welding speed to improve the productivity.
TIG 320 400 AC/DC-series welding machine is suitable for all positions welding for various plates
made of stainless steel, carbon steel, alloyed steel, titanium, aluminium, magnesium, cuprum, etc, which
is also applied to pipe installment, mould mend, petrochemical, architecture decoration, car repair,
bicycle, handicraft and common manufacture.
MMA——Manual Metal Arc welding;
PWM——Pulse-Width Modulation;

SUMMARY
8
IGBT——Insulation Gate Bipolar Transistor
TIG——Tungsten Insert Gas welding
§2.2 Module Explanation
The module explanation of arc welding machine must accord with the correlative prescripts of
National Standard GB10249. It is explained as the following (take TIG 320 AC/DC PULSE as an
example).
TIG 320 AC/DC PULSE
PULSE
AC/DC welding machine
Max welding current 320A
TIG welding machine/MMA
§2.3 Working Principle
The working principle of TIG 320 400 AC/DC welding machines is shown as the following figure.
Three-phase 380V work frequency AC is rectified into DC (about 312V), then is converted to medium
frequency AC (about 20KHz) by inverter device (IGBT module), after reducing voltage by medium
transformer (the main transformer) and rectifying by medium frequency rectifier (fast recovery diodes),
then is outputted DC or AC by selecting IGBT module. The circuit adopts current feedback control
technology to insure current output stably. Meanwhile, the welding current parameter can be adjusted
continuously and steplessly to meet with the requirements of welding craft.
Rectify Inverter
Medium
frequency
transformer
Medium
frequency
rectify
Hall device
Current positive-
feedback control
DC AC DCAC DC
380V,50HZ
Three-phases
AC

SUMMARY
9
§2.4 Volt-Ampere Characteristic
TIG 320 400 AC/DC welding machine has an excellent volt-ampere characteristic, whose graph is
shown as the following figure. The relation between the conventional rated loading voltage U2and the
conventional welding current I2is as follows:
When I2≤600A，U2=10+0.04I2(V); When I2＞600A,U2=34(V).
67
34
10
0600 I
2
（A）
U
2
（V）
Working
point
Volt-ampere characteristic The relation between the
conventional loading
voltage and welding current

INSTALLATION AND ADJUSTMENT
10
§3 Installation and Adjustment
§3.1 Parameters
Models
Parameters TIG 320 AC/DC PULSE TIG 400 AC/DC PULSE
Input power 3-380±10%，50/60Hz 3-380±10%，50/60Hz
Rated input current（A
）
21（TIG）27.5（MMA）26.5（TIG）36.5（MMA）
Rated input power
（KW）9.5（TIG）13（MMA）13（TIG）17.4（MMA）
Power factor 0.65 0.70
no-load voltage(V) 61 67
Adjustment range of
start current（A）10～welding current 10～welding current
Adjustment range of
welding current（A）10-320 10-400
Adjustment range of
downslope time（S）0～10 0～10
Pre-gas time（S）0~2 0~2
Adjustment range of
post-gas time（S）0～10 0～10
Clearance effect（%）5-95 5-95
Efficiency ≥85 ≥85
Duty cycle（40℃，
10 minutes）
60% 320A 60% 400A
100% 250A 100% 310A
Protection class IP23 IP23
Insulation class H H
Dimensions of Machine
（L×W×H）
（mm）550×240×445 550×240×445
Weight(Kg) 25.5 27

INSTALLATION AND ADJUSTMENT
11
3.2 Duty cycle & Over heat
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 right figure.
If the welder is over-heat, the IGBT over-heat
protection unit inside it will output an instruction to cut
output welding current, and brighten the over-heat
pilot lamp on the front panel. At this time, the machine
should be relaxed 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 Movement and placement
Please take care for the welder when moving it, and do not make it sloped.
It also can be moved by the handle on the top of the welder. Place the welder well when
moving it to the right position. When the machine gets to the destination, it needs to be fixed up to
avoid gliding.
When using forklift, its arm length must be long enough to reach the outside so as to ensure
lifting safely.
The movement may result in the potential danger or substantive hazard, so please make sure
that the machine is on the safe position before using it.

INSTALLATION AND ADJUSTMENT
12
§3.4 Power supply input connection
TIG 320 400 AC/DC welding machines’ power supply connects to 380V.
When the power supply voltage is over the safe work voltage, there are over voltage and
under voltage protection inside the welder, the alarm light will on, at the same time, the current
output will be cut off.
If the power supply voltage continually goes beyond the safe work voltage range, it will
shorten the welder life-span. The below measures can be used:
Change the power supply input net. Such as, connect the welder with the stable power supply
voltage of distributor;
Induce the machines using power supply in the same time;
Set the voltage stabilization device in the front of power cable input.
§3.5 Polarity Connection
（
MMA
）
MMA (DC): Choosing the connection of DCEN or DCEP according to the different electrodes.
Please refer to the electrode manual.
MMA (AC): No requirements for polarity connection.

INSTALLATION AND ADJUSTMENT
13
§3.6 Assembling the equipment (TIG)
Workpiece is connected to the positive electrode of welding machine, and welding torch is
connected to the negative electrode, which is called DC POSITIVE CONNECTION;
otherwise, that is called DC NEGATIVE CONNECTION. Generally, it is usually operated in
DC POSITIVE CONNECTION in TIG welding mode.
The control cable of torch switch consists of 2 wires, pedal control of 3 wires and the aero
socket has 14 leads.
Consumable parts for TIG torch, such as tungsten electrode、tip、gas nozzle、electrode
shield(short/long) , please enquire us by mail or phone according to the accessory codes.
When TIG 320 400 AC/DC welding machines are operated in HF ignition method, the
ignition spark can cause interferences in equipment near the welding machine. Be sure to
take specially safety precautions or shielding measures.

INSTALLATION AND ADJUSTMENT
14
§4 Operation
§4.1 Layout for the panel
1Positive output:The welder’s positive polarity output.
2Negative output: The welder’s negative polarity output.
3Aero socket: Is connected to torch switch control wire.（It has 14 leads and lead 8 - lead 9 are
connected to torch switch control wire）.
4Shield gas connector:Is connected to the gas input pipe of torch.
5Power source switch:Switch to “ON”, the welder is turned on, while switch to “OFF”, the welder
is turned off.
6Power source input:To connect power source.
7water box connector:To connect water box.
8Shield gas input joint:To connect one head of the gas hose while the other head of which is
connected to argon gas cylinder.

INSTALLATION AND ADJUSTMENT
15
§4.2 Control panel

INSTALLATION AND ADJUSTMENT
16

INSTALLATION AND ADJUSTMENT
17
Available parameters where 2T and 4T mode have been selected:
Tpr Gas pre-flow time
Unit S
Setting range 0.0—2.0
Is Starting current (only with 4T)
Unit A
Setting range 10—320 (TIG 320)；10—400(TIG 400)
Tup Upslope time
Unit S
Setting range 0.0—10
Ip Welding current
Unit A
10—320 (TIG-320)；10—400 (TIG-400)；
Ib Base current
Unit A
10—320 (TIG-320)；10—400 (TIG-400)；
Dcy Ratio of pulse duration to base current duration
Unit %
Setting range 5—95

MAINTENANCE AND TROUBLESHOOTING
18
Fp Pulse frequency
Unit Hz
Setting range 0.5—200
Tdown Downslope time
Unit S
Setting range 0—10
Ic Crater arc current (only with 4T)
Unit S
Setting range 10-320 TIG 320)；10-400 (TIG 400)
Tpo Gas post-flow time
Unit S
Setting range 0—10
AC frequency (only with TIG-AC)
Unit Hz
Setting range 50—250
Balance (only with TIG-AC)
Balance adjustment is mainly used to set the adjustment of eliminating metal-oxide (such as
Aluminium, Magnesium and its alloy) while AC output.
Unit
Setting range -5—+5