Strata EZITIG 205DC User manual

OPERATING INSTRUCTIONS
www.strata.co.nz
230V 50HZ
SINGLE
PHASE
IGBT
INVERTER
TECHNOLOGY
DIRECT
CURRENT
OUTPUT
SPIKE/
GENERATOR
SAFE
INTELLIGENT
PROTECTION
SYSTEM
IP23 CORROSION
& SALT SPRAY
RESISTANT
EZITIG 205DC
INVERTER WELDER
IMPORTANT!
To qualify for full 24 month warranty, you must register within 30 days of purchase. See inside for details.
Read these Operating Instructions Completely before attempting to use this machine. 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 anything in this manual.

CONTENTS
2 Overview ................................................................................... .7
1. EZITIG205DC Related Parts .................................................6
2.1 Features ......................................................................................................................7
2.2 Technical Data............................................................................................................7
2.3 Brief Introduction......................................................................................................8
9
2.4 Duty cycle and Over-heat..........................................................................................
2.5 Working Principle......................................................................................................10
2.6 Volt-Ampere Characteristic......................................................................................10
3 Installation & Operation..........................................................12
3.1 Layout for the front and rear panel .........................................................................12
3.2 Power supply input Connection................................................................................16
3.3 Installation & Operation for MMA Welding...........................................................17
3.3.1 Set up installation for MMA Welding..............................................................................17
3.3.2 Operation for MMA Welding...........................................................................................18
3.3.3 MMA Welding ...................................................................................................................19
3.3.4 MMA Welding Fundamentals..........................................................................................
20
3.3.5 MMA Welding trouble shooting.......................................................................................22
3.4 Installation & Operation for TIG Welding ...............................................................24
3.4.1 Set up installation for TIG Welding.................................................................................24
3.4.2 Operation for TIG Welding..............................................................................................25
3.4.3 Remote current control.....................................................................................................25
3.4.4 Tig Welding Techniques ....................................................................................................27
3.4.5 Electrodes...........................................................................................................................29
3.4.6 TIG Welding trouble shooting..........................................................................................34
3.5 ..................................................................................37
Wire foot pedal Configuration
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EZITIG 205DC

3.6 Operationenvironment .............................................................................................
3.7 Operation Notices ......................................................................................................
4 Maintenance & Troubleshooting.............................................
4.1 Maintenance ...............................................................................................................
4.2 Troubleshooting .........................................................................................................
4.3 List of error code........................................................................................................
4.4 Electrical schematic drawing....................................................................................43
38
38
39
40
42
39
44
49
Safety ............................................................................................
Warranty .....................................................................................
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EZITIG 205DC

Congratulations on the purchase of your new Stata Welding Product!
The Strata range of Welding Products from Euroquip utilises the latest design technology and is
engineered to produce welding products that combine market leading value, features and durability.
Designed for the discerning operator, who seeks professional results and quality. Design emphasis is
placed on simple design and functional operation. All Strata products are subject to stringent quality
control and are designed and manufactured to New Zealand and Australian standards.
Common applications for Strata products include:
• Engineering
• Automotive
• Manufacturing
• Farming
• Industrial Maintenance and Repair
For more industrial welding solutions, check out the full Strata Range from Euroquip at:
www.strata.co.nz
Euroquip is a market leading provider of innovative power equipment solutions to a wide range of
industries across Australasia.
Providing exceptional product support is a key component of Euroquip’s market leading customer
advantage program. As part of this program, it is required products to be registered with Euroquip to
qualify for extended product support. Products that are not registered with Euroquip are supported
by a base 12 month warranty only. Spare parts and after sales support may not be available for an
unregistered product outside of the base warranty period. If a Euroquip dealer has not already registered
your product, please register it online at www.euroquip.co.nz. To access a physical registration form,
please download one at www.euroquip.co.nz under the contact us tab.
4www.strata.co.nz
EZITIG 205DC

www.strata.co.nz
INVERTER TIG WELDER
•EZITIG 205DC •
* 24 Month Warranty only with online registration of product - www.strata.co.nz
EZITIG 205DC
TIGPULSE
FREQUENCY
STANDARDS WARRANTY
24 months*
with
registration
DIMENSIONS
(LxWxH)
WEIGHT INPUT POWER
SUPPLY
INPUT POWER
SUPPLY
TOLERANCE
MAXIMUM
INPUT CURRENT
GENERATOR
CAPACITY
MMA CURRENT
OUTPUT
MMA DUTY
CYCLE
TIG CURRENT
OUTPUT
410 x 146
x 278mm
7kg230V AC 15A
50/60Hz
±10%V 43A 10kVA5 -200A89V200A@15%
150A@60%
115A@100%
EN60974-1:
2012
5 -200A
TIG DUTY
CYCLE
TIG UP SLOPE
DOWN SLOPE
ADJUSTMENT
0-2/0-10s
INSULATION
CLASS
POWER
FACTOR
IP23 0.75
POWER
EFFICIENCY
85%
MMA
ROD SIZE
• IGBT inverter technology for smooth & stable welding
output and increased reliability
• Industrial IP23 casing with front panel protection resists damage,
moisture and corrosion
• Microprocessor control system for superior and dynamic arc
characteristics
• Lightweight & compact design, ideal for portable applications
• Extreme stress tested in production up to 440V, ensuring rugged
reliability
• Great control and easy to use MMA welding with adjustable arc
force, hot start and auto anti-stick control
• Lift TIG and HF start modes gives versatility when welding around
sensitive electronic equipment
• Electronic HF TIG arc ignition system, contamination free and easy
arc starting with low EMF interference
• Spot welding function with 2T/4T trigger control
• Durable and reliable with high quality & over specified electronic
components
• Intelligent protection system with temperature, voltage and current
sensors for increased reliability and safety
• Designed to work with generator power supply with protection from
power surges.
• Multi PCB construction is economical to service and repair
compared to single PCB design
• Potententiometer torch/ foot pedal remote control with finger tip
remote control (optional)
• All remote functions connect through single plug 12 pin connection
• Quick connect inlet gas fitting
• Accessories include 3m earth lead with heavy duty earth clamp,
4m MMA lead with heavy duty twist lock electrode holder,
Strata Professional PRO26 12ft TIG torch with composite machine
connection, 2 stage flowmeter, argon gas regulator, 4m gas hose,
gas inlet quick connector and hose clamps.
MMA O/C
VOLTAGE
200A@20%
155A@60%
120A@100%
0.5 - 200Hz
TIG PULSE
WIDTH RANGE
5 - 95% 1.6 - 5.0mm
The EZITIG 205DC is a powerful highly portable, easy to use machine. Extreme stress tested to 440V with
IP23 protection, the EZITIG 205DC is built to last in the harshest NZ work environments.
DIRECT
CURRENT
CORROSION
RESISTANT
SPIKE/
GENERATOR
SAFE
IGBT
INVERTER
TECHNOLOGY
INTELLIGENT
PROTECTION
SYSTEM
230V 50HZ
SINGLE
PHASE

1. EZITIG205DC Related Parts
DescriptionPart number
17373 Pro-Grip 26 Torch X 25Ft, Tgc End (Large Dinse) M12, 10K Pot And 12 Pin Remote Plug
DCKIT DC Tig Consumables Starter Kit - WP17, WP18, WP26
SW17847 12 Pin Strata TIG Remote Connection Plug
TBC57Y02 Long black cap
TER1MS-10 Ergo Tig Switch - 10k Pot
TC10N23 Collet 1/16 (1.6mm) (2 pk)
TC10N24 Collet 3/32 (2.4mm) (2 pk)
TC10N25 Collet 1/8 3.2mm (Pkt 2)
Collet Bodies
TCB10N31 Collet body 1/16 (1.6mm) (2pk)
TCB10N32 Collet body 3/32 (2.4mm) (2pk)
TCB10N28 Collet body 1/8 (3.2mm) (2 pk)
Ceramic Cups
TCC10N48 Std. ceramic cup 10mm bore #6 (2pk)
TCC10N47 Std. ceramic cup 11mm bore #7 (2pk)
TCC10N46 Std. ceramic cup 13mm bore #8 (2pk)
TCC10N45 Std. ceramic cup 16mm bore #10 (2pk)
MMA Consumables
AAL3550 Arc Lead 25mm2 cable, 35-70mm plug, 4m 300A Twist-lock Electrode holder
AEL3550 Earth Lead 25mm2 cable, 35-70mm plug, 3m 300A Heavy duty earth clamp
Regulators
GR101ARFL Argon regulator c/w flow tube
GR101AR-2FL Argon regulator c/w twin flow tubes
SW17844 Gas hose coupling
EZITIG205DC
TIG Torch & Consumables
Collets
Variable Amp
Gas Hose
For Gas lens Parts Please see the Strata Consumables Guide.
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EZITIG 205DC

2 Overview
2.1 Features
Lift TIG and HF Start Modes for versatility when
welding around sensitive electronic equipment.
Adjustable arc force, hot start & anti stick control
for greater control and ease of use when MMA
welding.
High performance on ultra thin surfaces with no
deformation.
2T/4T trigger control.
Digital display meter for accurate setting &
feedback of welding output.
Equipped with temperature/phase loss protection；
voltage and current sensors for high protection.
Designed to work with diesel generators and to
avoid failures due to its voltage spikes.
Up/ Down Button Remote Control torch (optional).
Roller wheel amps control on torch. (optional)
Wireless Remote Control . (optional)
Wire Foot Pedal. (optional)
2.2 Technical Data
Models
Parameters
EZITIG205DC
Power Supply Voltage
(V)
1~220V/230V/240V±10%
Frequency(HZ) 50/60
Rated input current
（A）43 MMA/ 34 TIG
Rated input power
（KW）6.2 MMA/ 4.9 TIG
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Duty cycle (40℃10
min)
35% 200A
60% 155A
100% 120A
Welding Current
Range （A）5-200
Up slope/Down slope
(S) 0-10
Pre/Post Flow (S) 0-2/0-10
Pulse frequency (HZ) 0.5-200
Pulse width range (%) 5-95
No Load Voltage(V) 89
Efficiency(%) ≥85%
Power Factor 0.75
Insulation class H
Protection class IP23
Cooling AF
Net Weight(Kg) 7.5
Dimensions(mm) 410*150*300
Note: The above parameters are subject to change with future machine improvement!
2.3 Brief Introduction
TIG series of welding machines adopt the latest Pulse Width Modulation (PWM) technology
and the Insulated Gate Bipolar Transistor (IGBT) power modules. It uses switching frequencies in
the 20KHz-50KHz ranges so as to replace the traditional line-frequency transformer type welding
machines. Thus, machines are characterized with portability, small size, lightweight, low energy
consumption and noise, etc.
The parameters of the machine 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, 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.
EZITIG205DC PULSE Characteristics：
★DC Pulsed TIG and MMA, adopt IGBT and advanced PWM technology
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EZITIG 205DC

★High performance MCU, Digital control, Digital display
★Preset all parameters with hold process
★HF/Lift TIG, current down slope and up slope, gas post-flow, Pulse Frequency
★Intelligent protection: over-voltage, under-voltage, over-current, over-heat
1. For MMA, polarity connection can be chosen according to different electrodes，please
refer to §3.3.1；
2. 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;
3. 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 series of welding machines is suitable for all positions welding for various plates made
of stainless steel, carbon steel, alloyed steel, titanium, 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 Arcwelding;
PWM——Pulse-Width Modulation;
IGBT——Insulation Gate Bipolar Transistor;
TIG——Tungsten Inert Gas welding.
2.4 Duty cycle and Over-heat
The letter “X” stands for Duty Cycle, which is defined as the portion of the time a welding
machine can weld continuously with it’s rated output current within a certain time cycle (10
minutes).
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EZITIG 205DC

The relation between the duty cycle “X” and the output welding current “I” is shown as the
right figure.
If the welding machine is overheating, the
IGBT over-heat protection sensing will send a
signal to the welding machine control unit to
cut the output welding current OFF and light
the over-heat pilot lamp on the front panel. In
that case, the machine should not be welding
for 10-15 minutes to cool down with the
fanrunning. When operating the machine again,
the welding output current or the duty cycle
should be reduced.
2. 5 Working Principle
The working principle of TIG series of welding machines is shown in the following figure.
Single-phase 220V line frequency AC is rectified into DC (about 315V), then is converted to
medium frequency AC (about 40KHz) by inverter device (IGBT), after reducing voltage by
medium transformer (the main transformer) and rectified by medium frequency rectifier (fast
recovery diode), and is outputted by inductance filtering. The circuit adopts current feedback
control technology to ensure current output stability. Meanwhile, the welding current
parameters can be adjusted continuously and steplessly to meet with the requirements of welding
craft.
2. 6 Volt-Ampere Characteristic
TIG series of welding machines has excellent volt-ampere characteristic. Referring to the
following graph. In TIG welding, the relation between the rated loading voltage U2and welding
Rectify Inverter
Medium
frequency
transformer
Medium
frequency
rectify
Hall device
Current positive-
feedback control
Three-phase, AC DC AC DC
380V，50Hz
AC DC
Single-phase, AC
220V, 50HZ
Relation of welding current and
duty cycle for EZITIG205DC
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EZITIG 205DC

current I2 is as follows:
When I2≤600A，U2＝10＋0.04 I2（V）；When I2＞600A，U2＝34（V）.
67
34
10
0 600 I
2
（A）
U
2
（V）
Working
point
Volt-ampere characteristicThe relation betweenthe
conventional loading
voltage and welding current
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3 Installation & Operation
3.1 Layout for the front and rear panel
（1）“-” Output terminal.
（2）
（3）TIG gas connection.
（4）“+” Output terminal.
（5）Power switch
（6）Input power cable.
（7）Inlet gas connector.
Control Panel
（8）Welding output mode button.
（9）MMA mode indicator .
（10）Lift TIG mode indicator. *
（11）Hf TIG mode indicator. *
（12）Trigger control mode button. *
（13）2T trigger indicator.
（14）4T trigger indicator.
（15）Digital display value current indicator.
（16）Spot welding.
（17）Alarm indicator. *
（18）Digital multifunction display. *
（19）Digital display value time indicator.
（20）Digital display value percentage indicator.
（21）Digital display value frequency indicator.
（22）Parameter select/adjust Knob. *
（23）TIG parameter setting indicator. *
（24）MMA arc force setting Indicator. *
（25）Pulse welding.
（26）MMA hot start setting Indicator. * （27）Pulse welding off.(28) Power Indicator.
TIG torch remote connection socket.
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EZITIG 205DC

*Denotes more detailed explanation of function to follow.
Further Controls Explained
TIG HF/ Lift Ignition Modes (10,11)
For TIGwelding process, contact of the torch tungsten to the workpiece will cause contamination
of the tungsten and the workpiece that will adversely affect the weld quality, especially when the
tungsten is electrically energised.
HF Ignition(High Frequency) sends a pulse of high energy electricity through the torch system that
is capable of ‘jumping’ between the tungsten and the workpiece, ensuring arc starting without any
contact between the tungsten and workpiece. The disadvantage of HF ignition is that the high ener-
gy electricalpulse creates significant electrical and radio signal interference, which limits its use
around sensitive electronic equipment such as computers.
Lift TIG Ignition is a compromise that minimises tungsten contamination while eliminating the
electrical interference of HF startsystems. Lift arcstarting works by lightly resting the tungsten
on the work piece, activating the torch trigger signal and then lifting the tungsten off. The control
circuit will sense when the tungsten is removed from the work piece and send a low powered pulse
of electricity through the tungsten that will cause the TIG arc to initiate. Because the tungsten is not
‘live’ when it is in contact with the work, contamination is minimised.
TIG 2T/4T Trigger Control (12)
2T mode the trigger is pulled and held on to activate the welding circuit, when the trigger is
released, the welding circuit stops. 4T is known as‘latching’mode. The trigger is pulled once and
released to activate the welding circuit, pulled and released again to stops the welding circuit. This
function is useful to longer welds as the trigger is not required to be held on continuously. TIG
series of welding machines also has more advanced current controls that can be used in 4T mode.
Alarm Indicator (17)
Lights when over voltage, over current or electrical overheating (due to exceeding duty cycle) is
detected and protection is activated. When protection is activated, welding output will be disabled
until the safety system senses the overload has reduced sufficiently and indicator lamp goes out.
May also trigger if machine experiences an internal power circuit failure.
Digital Multifunction Display (18)
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Before welding displays the setting selected/being adjusted using the control knob (22). During
welding, displays welding current. The parameter setting displayed is indicated bythe LEDs 15,
16, 17,19,20,21. If left inactive for several seconds,display will revert back to main welding
current setting.
Parameter Select/ Adjust Knob (22)
Switch between welding parameter settings by pressing this knob, adjust by turning the knob.
Value of the parameter selected will be shown on the digital multifunction display (18).
TIG Parameter Setting
Pre gas flow setting indicator (1)
Controls the period shielding gas will flow for when the torch is triggered before the arc starts.
This purges the work area of atmospheric gas which could contaminate the weld before the weld
starts. Unit(S) and setting range (0-2S).
Start current setting indicator (2)
Available in 4T trigger mode, sets a welding current 5-100% of the main welding current
activated when the trigger is held on to ‘latch’ the trigger before the main weld current is started.
Once the trigger is released, the current will go through the upslope (3) period if it is set, to the
main welding current (4).
Up slope setting indicator (3)
When the trigger is activated, the welding current will increase gradually over the time selected
up to the set main welding current (4). Unit(S) and setting range (0-10S).
TIG welding current setting indicator (4)
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EZITIG 205DC

Sets the main welding current . Unit(A) and setting range (5-200A).
Base current setting indicator (5)
Only available when pulse mode (12) is selected. Sets the current of the low/ base pulse. Unit(A)
and setting range (5-200A).
Down slope setting indicator (6)
When the trigger is released, the welding current will reduce gradually over the time selected
down to 0. This allows the operator to complete the weld without leaving a ‘crater’ at the end of
the weld pool. Unit(S) and setting range (0-10S).
End current setting indicator (7)
Available in 4T trigger mode, sets a welding current 5-100% of the main welding current activat-
ed when the trigger is held on to ‘unlatch’ the trigger before the weld is finished. If downslope (6)
is set, the current will go through the downslope period before going to the end current set. When
the trigger is released, the arc will stop.
Post gasflow setting indicator (8)
Controls the period of time the shielding gas continues to flow for after the arc is stopped. This
protects the weld area and torch tungsten from contamination while it is still hot enough to react
with atmospheric gases, after the weld is finished. Unit(S) and setting range (0-10S).
Pulse width setting indicator (9)
Only available when pulse mode (12) is selected. Sets the time proportion as a percentage
between the peak current and base current when using pulse mode. Neutral setting is 50%, the
time period of the peak current and base current pulse is equal. Higher pulse duty setting will give
greater heat input, while lower pulse duty will have the opposite effect. Unit(%) and setting range
(5-95%).
Pulse frequency setting indicator (10)
Only available when pulse mode (12) is selected. Sets the rate that the welding output alternates
between the peak and base current settings. Unit(Hz) and setting range (0.5-200Hz).
Pulse welding
Pulse welding mode switches the welding output between a high and low current output in a
cyclical manner. When used correctly this function has substantial benefits in the TIG welding
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process including greater weld penetration for less work heat input and greater control of the weld
pool.
The basic theory for setting the base current using pulse mode is that the base current should be
sufficient to maintain the existing molten weld pool, while the peak current is sufficient to melt
new metal in order to move/ expand the molten weld pool. Increased pulse frequency will have
the effect of making the arc more tightly focused which is useful for fine stainless work and
similar. Pulsing can also be used to help move the weld pool, this technique is useful for welding
out of position or with materials that have higher viscosity weld pool. Higher pulse duty setting
will give greater heat input, while lower pulse duty will have the opposite effect.
MMA parameter settings
Hot start (26)
Hot start provides extra power when the weld starts to counteract the high resistance of the
electrode and workpiece as the arc is started. setting range (0-10).
Arc force (24)
An MMA welding power source is designed to produce constant output current (CC).This means
with different types of electrode and arc length; the welding voltage varies to keep the current
constant. This can cause instability in some welding conditions as MMA welding electrodes will
have a minimum voltage they can operate with and still have a stable arc.
Arc Force control boosts the welding power if its senses the welding voltage is getting too low.
The higher the arc force adjustment, the higher the minimum voltage that the power source will
allow. This effect will also cause the welding current to increase. 0 is Arc Force off, 10 is
maximum Arc Force. This is practically useful for electrode types that have a higher operating
voltage requirement or joint types that require a short arc length such as out of position welds.
3.2 Power supply input Connection
The TIG series of welding machines is designed to operate on a 220V AC power supply.
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
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EZITIG 205DC

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.
3.3 Installation & Operation for MMA Welding
3.3.1 Set up installation for MMA Welding
Connection of Output Cables Two sockets are available on this welding machine. For MMA
welding the electrode holder is shown be connected to the positive socket, while the earth lead
(work piece) is connected to the negative socket, this is known as DCEP. However various
electrodes require a different polarity for optimum results and careful attention should be paid to
the polarity, refer to the electrode manufacturers information for the correct polarity.
DCEP: Electrode connected to “+”output socket.
DCEN: Electrode connected to“-”output socket.
(1) Connect the earth lead to “-”,tighten clockwise;
(2) Connect the earth clamp to the work piece. Contact with the work piece must be firm contact
with clean, bare metal, with no corrosion, paint or scale at the contact point.
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(3) Connect the electrode lead to “+”,tighten clockwise;
(4) Each machine is equipped with a power cable should be based on the input voltage welding
power cable connected to the appropriate position, not to pick the wrong voltage;
(5) With the corresponding input power supply terminal or socket good contact and prevent
oxidation;
(6) With a multi meter measure the input voltage is within the fluctuation range;
(7) The power ground is well grounded.
3.3.2 Operation for MMA Welding
(1) According to the above method to install is correct, turn the power switch, so that the power
switch is “ON” position, then the power indicator light, the fan comes on, the device work
properly.
(2) Set the welding mode button to ‘MMA’.
(3) Set the welding parameters as required using the parameters control knob (following the
instructions in the previous section).
(4) Place the electrode into the electrode holder and clamp tight.
(5) Strike the electrode against the work piece to create and arc and hold the electrode steady to
maintain the arc.
(6) Commence welding. If necessary, readjust the Welding parameters control knob to obtain the
welding condition required.
(7) After completion of welding the Power Source should be left turned ON for 2 to 3 minutes.
This allows the fan to run and cool the internal components.
(8) Switch the ON/OFF Switch (located on the rear panel) to the OFF position.
NOTE:
Note the polarity of wiring, the general DC welding wire in two ways. Selected according to
the technical requirements of welding the appropriate connection, if you choose incorrectly
will result in arc instability and spatter large adhesion and other phenomena, such cases can
be quickly reversed to joints.
If the work piece distance from the welding machine, the second line(electrode holder and
ground) is longer, so choose the appropriate conductor cross-sectional area should be larger to
reduce cable voltage drop.
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3.3.3 MMA Welding
One of the most common types of arc welding is manual metal arc welding (MMA) or stick
welding. An electric current is used to strike an arc between the base material and a consumable
electrode rod or ‘stick’. The electrode rod is made of a material that is compatible with the base
material being welded and is covered with a flux that gives off gaseous vapours that serve as a
shielding gas and providing a layer of slag, both of which protect the weld area from atmospheric
contamination. The electrode core itself acts as filler material the residue from the flux that forms
slag covering over the weld metal must be chipped away after welding.
●The arc is initiated by momentarily touching the electrode to
the base metal.
●The heat of the arc melts the surface of the base metal to
form a molten pool at the end of the electrode.
●The melted electrode metal is transferred across the arc into
the molten pool and becomes the deposited weld metal.
●The deposit is covered and protected by a slag which comes
from the electrode coating.
●The arc and the immediate area are enveloped by an
atmosphere of protective gas.
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Manual metal arc ( stick) electrodes have a solid metal wire
core and a flux coating. These electrodes are identified by the
wire diameter and by a series of letters and numbers. The
letters and numbers identify the metal alloy and the intended
use of the electrode.
The Metal Wire Core works as conductor of the current that
maintains the arc. The core wire melts and is deposited into the
welding pool.
The covering on a shielded metal arc welding electrode is
called Flux.
The flux on the electrode performs many diferent functions.
These include:
●producing a protective gas around the weld area
●providing fluxing elements and deoxidizer
●creating a protective slag coating over the weld as it cools
●establishing arc characteristics
●adding alloying elements.
Covered electrodes serve many purposes in addition to
filler metal tothe molten pool. These additional functions are
provided mainly by the covering on the electrode.
3.3.4 MMA Welding Fundamentals
Electrode Selection
As a general rule, the selection of an electrode is straight forward,in that it is only a matter of
selecting an electrode of similar composition to the parent metal. However, for some metals there
is a choice of several electrodes, each of which has particular properties to suit specific classes of
work. It is recommend to consult your welding supplier for the correct selection of electrode.
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EZITIG 205DC