Wilkinson Star Jasic TIG Series User manual

2
Your new product
Thank you for selecng this Jasic Technology, Wilkinson Star product.
This product manual has been designed to ensure that you get the most from your new product. Please
ensure that you are fully conversant with the informaon provided paying parcular aenon to the
safety precauons. The informaon will help protect yourself and others against the potenal hazards
that you may come across.
Please ensure that you carry out daily and periodic maintenance checks to ensure years of reliable and
trouble free operaon.
Wilkinson Star Limited are a leading supplier of equipment in the UK and our products are supported by
our extensive service network. Call your distributor in the unlikely event of a problem occurring. Please
record below the details from your product as these will be required for warranty purposes and to
ensure you get the correct informaon should you require assistance or spare parts.
Date purchased ________________________________________
From where ________________________________________
Serial Number ________________________________________
(The serial number will normally be located on the equipment top or underside of the machine and begin
with leers i.e. AA*****)
PLEASE REGISTER YOUR PRODUCT ONLINE AT WWW.JASIC.CO.UK/REGISTER
When all entry elds are complete the system will show a short message thanking you for a successful
registraon.
Disclaimer
Whilst every eort has been made to ensure that the informaon contained within this manual is
complete and accurate, no liability can be accepted for any errors or omissions. Please note products are
subject to connual development and may be subject to change without noce.
This manual should not be copied or reproduced without the wrien permission of Wilkinson Star
Limited

3
CONTENTS
Index Page
Your New Product 2
Index 3
Safety 4
Product Overview 7
Technical Specicaons 8
Descripon of Controls 10
Controls 12
Installaon 14
Operaon MMA 16
Operaon TIG 19
Torch Trigger Operaon Modes 26
Remote Control Socket 27
Maintenance 28
Troubleshoong 29
Welding Troubleshoong 30
EC Declaraon of Conformity 31
Disposal 31
RoHS Compliance Declaraon 31
Statement of Warranty 32
Wilkinson Star Jasic Technology Contact Details 36

4
SAFETY
These general safety norms cover both arc welding machines and plasma cung machines unless
otherwise noted.
The equipment must only be used for the purpose it was designed for. Using it in any other way could
result in damage or injury and in breach of the safety rules.
Only suitably trained and competent persons should use the equipment. Operators should respect the
safety of other persons.
Prevenon against electric shock
The equipment should be installed by a qualied person and in accordance with current standards in
operaon. It is the users responsibility to ensure that the equipment is connected to a suitable power
supply. Consult with your ulity supplier if required.
If earth grounding of the work piece is required, ground it directly with a separate cable.
Do not use the equipment with the covers removed.
Do not touch live electrical parts or parts which are electrically charged.
Turn o all equipment when not in use.
Cables (both primary supply and welding) should be regularly checked for damage and overheang.
Do not use worn, damaged, under sized or poorly jointed cables.
Ensure that you wear the correct protecve clothing, gloves, head and eye protecon.
Insulate yourself from work and ground using dry insulang mats or covers big enough to prevent any
physical contact with the work ground.
Never touch the electrode if you are in contact with the work ground or another electrode from a
dierent machine.
Do not wrap cables over your body.
Ensure that you take addional safety precauons when you are welding in electrically hazardous
condions such as damp environments, wearing wet clothing and metal structures.
Try to avoid welding in cramped or restricted posions.
Ensure that the equipment is well maintained. Repair or replace damaged or defecve parts immediately.
Carry out any regular maintenance in accordance with the manufacturer’s instrucons.
Safety against fumes and welding gases
Locate the equipment in a well-venlated posion.
Keep your head out of the fumes. Do not breathe the fumes.
Ensure the welding zone is in a well-venlated area. If this is not possible, provision should be made for
suitable fume extracon.
If venlaon is poor, wear an approved respirator.
Read and understand the Material Safety Data Sheets (MSDS’s) and the manufacturer’s instrucons for
metals, consumable, coangs, cleaners and de-greasers.
Do not weld in locaons near any de-greasing, cleaning or spraying operaons. Be aware that heat and
rays of the arc can react with vapours to form highly toxic and irritang gases.
Do not weld on coated metals unless the coang is removed from the weld area, the area is well
venlated and while wearing an air-supplied respirator. The coangs on many metals can give o toxic
fumes if welded.
Prevenon against burns and radiaon
Arc rays from the welding process produce intense, visible and invisible (ultraviolet and infrared) rays that
can burn eyes and skin.
Wear an approved welding helmet ed with a proper shade of lter lens to protect your face and eyes
when welding or watching.

5
SAFETY
Wear approved safety glasses with side shields under your helmet.
Never use broken or faulty welding helmets.
Always ensure that there are adequate protecve screens or barriers to protect others from ash, glare
and sparks from the welding area. Ensure that there are adequate warnings that welding or cung is
taking place.
Wear suitable protecve ame resistant clothing.
The sparks and spaer from welding, hot work pieces and hot equipment can cause res and burns.
Welding on closed containers, such as tanks, drums or pipes can cause them to explode.
Accidental contact of the electrode to metal objects can cause arcs, explosion, overheang or re.
Check and be sure the area is safe and clear of inammable material before carrying out any welding.
Protecon against noise
Some welding and cung operaons may produce noise.
Wear safety ear protecon to protect your hearing.
Protecon from moving parts
When the machine is in operaon keep away from moving parts such as motors and fans. Moving parts,
such as the fan, may cut ngers and hands and snag garments.
Protecons and coverings may be removed for maintenance only by qualied personnel, aer rst
disconnecng the power supply cable.
Replace the coverings and protecons and close all doors when the intervenon is nished and before
starng the equipment.
Take care to avoid geng ngers trapped when loading and feeding wire during set up and operaon.
When feeding wire be careful to avoid poinng it at other people or towards your body.
Always ensure machine covers and protecve devices are in operaon.
Precauons against re and explosion
Avoid causing res due to sparks and hot waste or molten metal.
Ensure that appropriate re safety devices are available near the cung/welding area.
Remove all ammable and combusble materials from the cung/welding zone and surrounding areas.
Do not cut/weld fuel and lubricant containers, even if empty.
These must be carefully cleaned before they can be cut/welded.
Always allow the cut/welded material to cool before touching it or placing it in contact with combusble
or ammable material.
Do not work in atmospheres with high concentraons of combusble fumes, ammable gases and dust.
Always check the work area half an hour aer cung to make sure that no res have begun.
Risks due to magnec elds
The magnec elds created by high currents may aect the operaon of pacemakers or electronically
controlled medical equipment.
Wearers of vital electronic equipment should consult their physician before beginning any arc welding,
cung, gouging or spot welding operaons.
Do not go near welding equipment with any sensive electronic equipment as the magnec elds may
cause damage.

6
SAFETY
RF Declaraon
Equipment that complies with direcve 2004/108/EC concerning electromagnec compability (EMC)
and the technical requirements of EN60974-10 is designed for use in industrial buildings and not those for
domesc use where electricity is provided via the low voltage public distribuon system.
Dicules may arise in assuring class A electromagnec compability for systems installed in domesc
locaons due to conducted and radiated emissions.
In the case of electromagnec problems, it is the responsibility of the user to resolve the situaon.
It may be necessary to shield the equipment and t suitable lters on the mains supply.
LF Declaraon
Consult the data plate on the equipment for the power supply requirements.
Due to the elevated absorbance of the primary current from the power supply network, high power
systems aect the quality of power provided by the network. Consequently, connecon restricons or
maximum impedance requirements permied by the network at the public network connecon point
must be applied to these systems.
In this case, the installer or the user is responsible for ensuring the equipment can be connected,
consulng the electricity provider if necessary.
Handling of compressed gas cylinders and regulators
All cylinders and pressure regulators used in welding operaons should be handled with care.
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.
Always secure the cylinder safely.
Never deface or alter any cylinder

7
PRODUCT OVERVIEW
The Wilkinson Star Jasic Technology TIG inverter range of welding machines have been designed as
integrated and portable welding power supplies units incorporang the most advanced IGBT inverter
technology in power electronics with easy operaon and adjustment due to friendly user interface.
Wilkinson Star Jasic Technology TIG 500D AC/DC Product Features:
 100Khz inverter frequency for high eciency oering reduced weight and volume
 TIG AC square wave, DC TIG and AC/DC MMA are available
 TIG AC and DC pulse mode
 MCU intelligent digital control (Soware)
 2T/4T trigger control
 Pre and post gas ow me, full up and down slope control
 Pulse adjustment, frequency, pulse duty and arc force
 100KHz frequency for reduced weight/volume
 Adjustable AC frequency and AC wave balance
 Hot start arc ignion funcon which ensures excellent arc
ignion in MMA for easier and more reliable arc starng
 Built in adjustable arc force technology which maintains the
opmum MMA arc condions during welding even with long
cables
 Oers excellent weld characteriscs and suitable for a wide
range of electrodes in MMA
 Easy arc starng, low spaer, stable current which oers
good weld bead shape
 Wide input voltage range tolerance
 Remote control opon available
 High quality nish to mouldings and handle
 Air cooled or water cooled opons available

8
TECHNICAL SPECIFICATIONS
Parameter Model
TIG500P AC DC
Input
Rated input power supply Three-phase AC400V 50/60Hz
Rated input capacity (KVA) 21
Power factor 0.85
MMA
output
Rated no-load voltage (V) 68
Rated maximum output (A/V) 400/36
Welding current range DC (A) 10~410
Welding current range AC (A) 20~410
Arc force current range (A) 0~250
Arc ignion current range (A) 10~410
AC frequency (Hz) 50
Output characterisc CC
TIG
output
Rated maximum output (A/V) 500/30
DC
Welding current range (A) 10~500
Peak / base current range (A) 20~500
Inial current range 10~500
Pulse frequency range (Hz) 0.5~200
Pulse duraon range (%) 10~90
AC
Rated maximum output (A/V) 500/30
Welding current range (A) 10~500
Peak / base current range (A) 20~500
Inial current range 10~500
Pulse frequency range (Hz) 0.5~200
Pulse duraon range (%) 10~90
Inial current range (A) 5~400
Pilot arc current range (A) 5~400
Up slope me range (s) 0~10
Base current range (A) 5~400
Peak current range (A) 5~400
Downslope me range (s) 0~10
Post-ow me range (s) 0~15
Pulse frequency range (Hz) 0.5~200
Pulse duraon rao range (%) 10~90
Spot welding me 0.1~10
Arc ignion mode HF /Li arc ignion
Output characterisc CC

9
TECHNICAL SPECIFICATIONS (Connued)
Working temperature range (0C) -10~+40
Environment Storage temperature range (0C) -25~+55
Humidity (%) ≤90% (no water condensate)
Structure
Enclosure ingress protecon IP21S
Cooling mode Forced air cooling
Rated duty cycle (%) MMA:30 TIG:50
Eciency (%) 85
Insulaon grade F
Overall size (L*W*H) 595*297*528
Weight (Kg) 30

10
DESCRIPTION OF CONTROLS
Front view
No. Part name Funcon
1Control panel To select welding mode and parameters
2Digital meter Display parameters
3Adjusng knob Adjust various parameters
4TIG parameters zone Adjusng various TIG parameters
5MMA parameters zone Adjusng various MMA parameters
6Water cooling selector Selecon of water or air cooling
7Remote control selector Selecon of remote control
8Air intake Air intake grill
9“+” output socket Connecon of work return
10 Control socket Connecon of torch switch or remote control
11 Power lamp Water cooler power indicator
12 Fuse Water cooler supply fuse
13 Water tank Water tank with ller cap
14 “-” output socket Connecon of TIG torch power cable
15 Gas connecon Outlet for shield gas to TIG torch
16 Inlet connector (red) Water return from torch connector
17 Outlet connector (blue) Water supply to torch connector
18 Water drain Drain cap

11
No. Part name Funcon
19 Switch Mains power switch
20 Socket Water cooling unit supply
21 Ground point External ground point
22 Mains cable Mains cable inlet
23 Fuse holder Protecon fuse
24 Fan guards Fan protecon
Rear View

12
CONTROLS
Control panel view JT-500D AC/DC
1. Welding mode selecon zone
2. Parameters selecon /display
zone
3. Parameters adjustment rotary
knob
4. MMA welding parameters
selecon zone
5. TIG parameters selecon zone
6. Remote control selector
7. Air / Water cooling selector
1. Welding mode selecon:
The welding mode switch allows the user to switch between AC square-wave TIG, AC
pulsed TIG, DC TIG, DC pulsed TIG, AC MMA and DC MMA with the corresponding LED
lit. However, if the LED ashes, it indicates that welding is being carried out in the
corresponding welding mode and that reselecon cannot be performed.
2. Parameter and alarm displays:
The digital meter is used for displaying funconal parameters and error codes, details are as below:
A. Generally, the digital meter displays the preset
current, mes, pulse duraon rao and frequency
with the corresponding LED A, S, % or Hz being lit.
Parameters can be adjusted by turning the adjustment
knob. The digital meter displays the welding current
during welding and parameters can be adjusted at this
me as well. The display also shows the parameter
being adjusted and aer 3 seconds will turn the
display back to showing welding current.
B. Press the key “↓” in this zone to shi the display of the digital meter between ‘A S % Hz’, V, trigger
mode and job recall with the corresponding LED lit. ‘V’ indicates the output voltage and is also used for
selecng the operaon mode of TIG welding “MEMORY” which can store 5 groups of parameters and
users may perform welding conveniently with these parameters.
C. The digital meter displays the soware version aer the machine is started and displays the preset
current 2 seconds later.
D. In the normal condion, all alarm LEDs are o. In case of any error, the corresponding LED will
illuminate and the digital meter will display the corresponding error code.
When the “OC” LED illuminates and the digital meter displays “E-0” or “E-1” it indicates that over current
occurs. Restart the machine and welding can be connued.

13
CONTROLS
When the “LV/OV” LED illuminates and the digital meter displays “E-2” it indicates that the mains voltage
is overly low or that the secondary inverter drive power source fails. In the former condion, welding can
be recovered when the mains voltage goes into normal. In the laer condion, please consult the service
department.
When the “OH” LED illuminates and the digital meter displays “E-3” or “E-4” it indicates that welding is
forced to stop because the main circuit of the machine is overheated. In this condion, it is unnecessary
to turn o the machine, but just wait a few minutes and then welding can be connued.
3. Parameter adjustment knob:
It is used to adjust all adjustable parameters.
4. TIG parameter selecon area:
1) Pre ow gas me
2) Inial current
3) Upslope me
4) Base current
5) Peak current
6) Downslope me
7) Final current
8) Post ow gas me
9) Pulse frequency
10) Pulse duraon rao
11) AC frequency
12) Wave balance
13) TIG welding parameter selecon keys
5. MMA parameter selecon area:
1) Arc ignion current
2) Arc ignion me
3) Welding current
4) Arc force current
5) MMA parameter selecon switch
6. Remote control selecon:
Selecng foot pedal will allow remote amperage to be controlled by pressing the foot pedal, pressing
down on the foot pedal will increase the welding current and releasing the
foot pedal will decrease the welding current.
To acvate foot control, press the control key unl the corresponding LED
is on.
The welding current should be set to at least 30amps (to avoid arc breaking
due to low current being set) and should not be higher than the preset
current. The foot control is only eecve in TIG mode.
7. Water selector
Selects either air or water cooled torch mode.

14
INSTALLATION
Unpacking
Check the packaging for any signs of damage.
Carefully remove the machine and retain the packaging unl the installaon is complete.
Locaon
The machine should be located in a suitable posion and environment. Care should be taken to avoid
moisture, dust, steam, oil or corrosive gases.
Place on a secure level surface and ensure that there is adequate clearance around the machine to
ensure natural airow.
Input connecon
Before connecng the machine you should ensure that the correct supply is available. Details of the
machine requirements can be found on the data plate of the machine or in the technical specicaons
table found on page 8 in the manual.
The equipment should be connected by a suitably qualied competent person. Always ensure the
equipment has a proper grounding.
Never connect the machine to the mains supply with the panels removed.
Gas connecons
Connect the gas hose to the regulator/owmeter located on the shield gas cylinder and connect the
other end to the machine.
Gas selecon
A shielding gas is necessary for TIG welding because it is important to keep oxygen away from the weld
pool. Shielding gas does this by replacing the oxygen around the weld pool.
Shielding gas for TIG welding is generally an inert gas with argon being the most commonly used inert gas
for TIG welding most metals.
Output connecons
Electrode polarity
In general when using manual arc welding electrodes the electrode holder is connected to the posive
terminal and the work return to the negave terminal.
"+" output terminal: For MMA connect the electrode holder
"-" output terminal: For MMA connect the work return lead
Always consult the electrode manufacturer’s data sheet if you have any doubts.
When using the machine for TIG welding the TIG torch should be connected to the negave terminal and
the work return to the posive terminal.
"+" output terminal: For TIG connect the work return lead
"-" output terminal: For TIG connect the TIG torch

15
INSTALLATION
MMA welding
Insert the cable plug with electrode holder into the “+” socket on
the front panel of the welding machine and ghten it clockwise.
Insert the cable plug of the work return lead into the “-” socket on
the front panel of the welding machine and ghten it clockwise.
See example shown opposite:
TIG welding
Insert the cable plug with the work clamp into the indicated work
clamp socket on the front panel of the welding machine and
ghten it clockwise.
Insert the power connecon plug of the TIG torch into the
indicated torch socket on the front panel of the machine and
ghten clockwise. Connect the gas quick connector into the outlet
on the machine front.
Connect the torch switch plug into the socket on the front panel.
Connect the water supply cables to the cooler unit.
Connect the gas hose to the regulator/owmeter located on the
shield gas cylinder and connect the other end to the machine.
See example shown opposite:

16
OPERATION
Before starng any welding acvity ensure that you have suitable eye protecon and
protecve clothing. Also take the necessary steps to protect any persons within the welding
area.
MMA welding mode
MMA (Manual Metal Arc), SMAW (Shielded Metal
Arc Welding) or just Sck Welding.
Sck welding is an arc welding process which melts
and joins metals by heang them with an arc
between a covered metal electrode and the work.
Shielding is obtained from the electrode outer
coang, oen called ux. Filler metal is primarily
obtained from the electrode core.
The electrodes outer coang called ux assists in
creang the arc and provides a shielding gas and
on cooling forms a slag covering to protect the weld
from contaminaon.
When the electrode is moved along the work piece at the correct
speed the metal core deposits a uniformed layer called the weld
bead.
Aer connecng the welding leads as detailed you will need to
switch the power switch on the back panel to “ON”.
Select MMA mode by switching to the welding mode selecon key
to either DC or AC depending on your welding applicaon (see
page 10). There is now open circuit voltage output at both output
terminals.
Ensure you check that you have the electrode polarity correct and
set the amperage on the machine suitable for the electrode being
used.
Please see the guide to amperages required below, although this
MMA welding electrode guide can vary depending on material,
work piece thickness, welding posion and joint form.
Electrode Diameter (mm) Recommended Welding Current (A)
1.6 25 ~ 45
2.0 35 ~ 65
2.5 50 ~ 90
3.2 60 ~ 130
4.0 100 ~ 180
5.0 150 ~ 250
6.0 200 ~ 310

17
OPERATION
Before starng any welding acvity ensure that you have suitable eye protecon and
protecve clothing. Also take the necessary steps to protect any persons within the welding
area.
MMA welding
Current and Voltage Changes in DC MMA
Current and Voltage Changes in AC MMA
Note:
t0 - Standby secon, no welding current, output no-load voltage
t1 - Arc striking secon, the length adjusted according to hot arc striking me
t2 - Arcing secon
t3 - Short circuit transion secon
I1 - Arc strike current
I2 - Operang current
I3 - Arc force current
U1 - Operang voltage
U0 - No-load voltage
MMA AC mode outputs - 50Hz sine wave.
Current I2 - The current of the arcing secon during welding, set by the user according to process
requirements

18
OPERATION
Before starng any welding acvity ensure that you have suitable eye protecon and
protecve clothing. Also take the necessary steps to protect any persons within the welding
area.
MMA welding
Arc force
Arc force refers to the slope of the current rise during a short circuit and it is set to increase the current
every millisecond on this machine. Aer a short circuit, the current rises from the set current according to
this slope. For example, when the current is set to 100A and the arc force is 10, the current value aer a
short circuit of 5ms is: 100+5*10=150A. If the short circuit state sll exists the arc force current can rise to
the permied maximum value of 270A. If the short circuit state lasts longer than 0.8 second, the welder
enters an sck mode where the current will drop to a low value and wait for the welder to break the
electrode free. The arc force value should be determined according to rod diameter, set current and
process requirements. Larger arc force results in quicker transion of the droplets and less freezing of the
rod into the weld pool, but too much arc force will increase the spaer. Low arc force will result in lower
spaer and good weld formaon, but somemes it will cause the arc to become so or cause scking.
In parcular, the arc force should be increased when welding thick rods at low current. The arc force is
generally 0-40.
There is no arc force current in MMA AC mode.
Hot start (ignion amps)
Hot start current is benecial to the arc strike as it reduces the tendency of welding rod and weld material
to sck. The size of the hot start striking current is generally determined according to rod type, the
specicaons and welding current. Rods with beer arc striking performance and small diameter
generally need lower hot start striking current, higher welding current oen will not need any hot start
current. The hot start striking me is related to the arc striking current. If the hot arc striking current is
large, the hot start me can be shortened.
During DC welding, the heat of the welding arc is dierent on the posive and negave electrodes.
Therefore, with a DC power supply the dierent polaries must be taken into account. The electrode
negave (DCEN) means that the welding rod is connected to the negave electrode of the power supply
and the work piece is connected to the posive outlet. At this me, the work piece acquires more heat,
features high temperature, deep molten pool and easy penetraon and it is suitable for welding thick
material. The electrode posive (DCEP) means that the welding rod is connected to the posive outlet of
the power supply and the work piece is connected to the negave outlet. At this me, the work piece
acquires less heat, features low temperature, shallow molten pool and dicult penetraon and it is
suitable for welding thin pieces.
If AC welding equipment is used for welding, the polaries of the arcs will change alternately and
instantaneously. Therefore, the two electrodes have same heang and basically same temperatures and
there is no problem in posive connecon and reverse connecon.

19
OPERATION
Before starng any welding acvity ensure that you have suitable eye protecon and
protecve clothing. Also take the necessary steps to protect any persons within the welding
area.
TIG welding
Terms used: TIG – Tungsten Inert Gas, GTAW – Gas Tungsten Arc
Welding.
TIG welding is an arc welding process that uses a non-consumable
tungsten electrode to produce the heat for welding.
The weld area is protected from atmospheric contaminaon by a
shielding gas (usually an inert gas such as argon or helium) and a
ller rod matching the base material is normally used, though some
welds, known as autogenous welds, are carried out without the
need for ller wire.
TIG process can be either DC or AC modes:
DC - Direct current for welding steel, stainless steel, copper etc.
AC - Alternang current for welding aluminium and it’s alloys.
DC TIG welding
 Connect the TIG torch leads as shown
 Ensure that a suitable inert gas supply is connected
 Switch the power switch on the back panel to “ON” the machine
is started with the power LED on and the fan working
 Select TIG mode by switching to the welding mode selecon key
to either TIG DC or TIG DC with pulse depending on your welding
applicaon (see page 10)
 Open the gas valve of the cylinder and adjust the gas regulator
and ow gas meter to obtain the desired ow rate. Press the
torch trigger briey, the solenoid valve will operate and gas will
ow
 Adjust the welding current according to the thickness of the work
piece to be welded (for a guide to welding parameters, please
refer to the table below)
 Hold the torch 2-4mm away from the work piece and then press
the torch trigger. Aer arc is ignited, the HF discharge will cease,
the current will maintain the preset value and welding can be
carried out
 Aer releasing the torch trigger, the welding
arc stops but gas connues owing for the
post ow me and welding ends
 Adjust the downslope me potenometer
to change the me according to the welding
process requirements
This amperage guide for TIG welding tungsten
sizes shown can vary depending on material,
work piece thickness, welding posion and joint
form.
Tungsten Size DC – Electrode Negave
1.0mm 15 – 80A
1.6mm 70 – 150A
2.4mm 150 – 250A
3.2mm 250A – 400A
4.0mm 400A – 500A
6.0mm 750A – 1000A

20
OPERATION
Before starng any welding acvity ensure that you have suitable eye protecon and
protecve clothing. Also take the necessary steps to protect any persons within the welding
area.
DC TIG welding
Ip: This parameter is set by the user according to process
requirements and is the normal welding current.
t1: Is the xed pre ow me which refers to the me from
when the torch switch is pressed to deliver shield gas before
arc striking. This is a xed me of 0.5s which ensures that the
argon has been delivered through the welding torch and to
the weld zone at the normal ow rate when the arc is struck.
t2: Is the adjustable post ow gas me of the shield gas which ows aer the arc is exnguished. Too long
a me will cause a waste of shield gas and too short a me will cause the weld to oxidize due to
premature shield gas ow and the weld cooling without the shield.
DC TIG welding with slope
Pre-gas me: Indicates the
me from when the torch
trigger is pressed to the arc
being ignited in non-contact
mode. Commonly, it should
be longer than 0.5s to make
sure that the gas has been
delivered to the welding
torch in normal ow before arc ignion. The pre ow me should be increased if the gas hose is long.
Inial current (I1): It is the current when arc is ignited by pushing the torch trigger and it should be set
according to users own technical requirements. If the inial current is high enough, arc is easier to ignite.
However, it should not be too high when welding thin plate, so as to avoid burn through the work piece
during arc ignion. In some operaon modes, the current can stay at the inial current value to preheat
the work piece or illuminate the weld area.
Upslope: Indicates the me taken for the current to rise from 0 to the preset value and it should be set
according to users technical requirements.
Ip: This parameter is set by the user according to process requirements and is the normal welding
current.
Downslope: Indicates the me taken for the current to fall from the preset value to 0 and it should be
set according to users technical requirements.
Final current: In some operaon modes, the arc does not stop aer current downslope but stays in the
nal arc state. The working current in this state is called pilot arc current and it should be set according to
users technical requirements.
Post gas me: It indicates the me from the welding current being cut o to the gas valve inside the
machine being closed. If it is too long, it will lead to a waste of shield gas; if it is too short, it will result in
the oxidaon of weld bead and electrode. With special material the me may be longer.