Würth EWI 160 User manual

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EWI 160 / EWI 200
ARC/TIG INVERTER WELDERS
General safety rules
WARNING: Read and understand all instructions. Failure to follow all instructions
listed below may result in serious injury.
CAUTION: Do not allow persons to operate or assemble this EWI series unit
until they have read this manual and have developed a thorought understanding
of how the EWI series welder works.
WARNING: The warnings, cautions, and instructions discussed in this
instruction manual cannot cover all possible conditions or situations that could
occur. It must be understood by the operator that common sense and caution are factors which cannot
be built into this product, but must be performed by the operator.
SAVE THESE INSTRUCTIONS
IMPORTANT SAFETY CONSIDERATIONS
1.1 Your Welding Environment
- Keep the environment you will be welding in free from flammable materials.
- Always keep a fire extinguisher accessible to your welding environment.
- Always have a qualified person install and operate this equipment.
- Make sure the area is clean, dry and ventilated. Do not operate the welder in humid, wet or poorly
ventilated areas.
- Always have your welder maintained by a qualified technician in accordance with local, state and
national codes.
- Always be aware of your work environment. Be sure to keep other people, especially children, away
from you while welding.
- Keep harmful arc rays shielded from the view of others.
- Mount the welder on a secure bench or cart that will keep the welder secure and prevent it from
tipping over or falling.
GB

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1.2 Your Welder’s Condition
- Check ground cable, power cord and welding cable to be sure the insulation is not damaged. Always
replace or repair damaged components before using the welder.
- Check all components to ensure they are clean and in good operating condition before use.
1.3 Use of Your Welder
CAUTION
Do not operate the welder if the output cable, electrode, torch, wire or wire feed system is wet. Do not
immerse them in water. These components and the welder must be completely dry before attempting to
use them.
- Follow the instructions in this manual.
- Keep welder in the off position when not in use.
- Connect ground lead as close as possible to the area being welded to ensure a good ground.
- Do not allow any of your body parts to come in contact with the welding wire if you are in contact
with the material being welded, ground or electrode from another welder.
- Do not weld if you are in an awkward position. Always have a secure stance while welding to prevent
accidents. Wear a safety harness if working above ground.
- Do not sling cables over, or wrap them around your body.
- Wear a full coverage helmet with appropriate shade (see ANSI Z87.1 safety standard) and safety
glasses while welding.
- Wear proper gloves and protective clothing to prevent your skin from being exposed to hot metals,
UV and IR rays.
- Do not overuse or overheat your welder. Allow proper cooling time between duty cycles.
- Keep hands and fingers away from moving parts and stay away from the drive rolls.
- Do not point torch at any of your body parts or anyone else's.
- Always use this welder in the rated duty cycle to prevent excessive heat and failure.
1.4 Specific Areas of Danger, Caution or Warning
Electrical Shock
WARNING
Electric arc welders can produce a shock that can cause injury or death. Touching
electrically live parts can cause fatal shocks and severe burns. While welding, all metal
components connected to the wire are electrically hot. Poor ground connections are a hazard, so
secure the ground lead before welding.
- Wear dry protective apparel: coat, shirt, gloves and insulated footwear.
- Insulate yourself from the work piece. Avoid contacting the work piece or ground.
- Do not attempt to repair or maintain the welder while the power is on.

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- Inspect all cables and cords for any exposed wire and replace immediately if found.
- Use only recommended replacement cables and cords.
- Always attach ground clamp to the work piece or work table as close to the weld area as possible.
- Do not touch the welding wire and the ground or grounded work piece at the same time.
- Do not use a welder to defrost frozen pipes.
Fumes and Gases
WARNING
- Fumes emitted from the welding process displace clean air and can result in injury or death.
- Do not breathe in fumes emitted by the welding process. Make sure your breathing air is clean and
safe.
- Work only in a well-ventilated area or use a ventilation device to remove welding fumes from the
environment where you will be working.
- Do not weld on coated materials (galvanized, cadmium plated or metals containing zinc, mercury or
barium). They will emit harmful fumes that are dangerous to breathe. If necessary use a ventilator,
respirator with air supply or remove the coating from the material in the weld area.
- The fumes emitted from some metals when heated are extremely toxic. Refer to the material safety
data sheet for the manufacturer’s instructions.
- Do not weld near materials that will emit toxic fumes when heated. Vapors from cleaners, sprays and
degreasers can be highly toxic when heated.
UV and IR Arc Rays
DANGER .
The welding arc produces ultraviolet (UV) and infrared (IR) rays that can cause injury to
your eyes and skin. Do not look at the welding arc without proper eye protection.
- Always use a welding mask (helmet) that covers your full face from the neck to top of head and to the
back of each ear.
- Ensure that mask is fitted with appropriate shade lens that meets ANSI standards as well as with safety
plate. For Welders under 160 Amps output, use a shade 10 lens; for above 160 Amps, use a shade
12. For more information refer to the ANSI Z87.1 standard.
- Cover all bare skin areas exposed to the arc with protective clothing and footware. Flame-retardant
cloth or leather shirts, coats, pants or coveralls are available for protection.
- Use welding protection curtains or other barriers to protect other people from the arc rays emitted
when welding.
- Warn people in your welding area when you are going to strike an arc so they can protect themselves.

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Fire Hazards
WARNING
Do not weld containers or pipes that contain or have had flammable, gaseous or liquid
combustibles in them. Welding creates sparks and heat that can ignite flammable and
explosive materials.
- Do not operate any electric arc welder in areas where flammable or explosive materials are present.
- Remove all flammable materials at least 10 m away from the welding arc. If removal is not possible,
tightly cover them with fireproof covers.
- Take precautions to ensure that flying sparks do not cause fire or explosion in hidden areas, cracks
or areas you cannot see.
- Keep a fire extinguisher readily accessible in case of fire.
- Wear oil-free clothing with no pockets or cuffs that might collect sparks (sparking debries).
- Do not carry in your pockets any combustible items such as lighters or matches.
- Keep the earth lead connected as close as possible to the welding place to prevent any unknown,
unintended paths of electrical current that might cause electrical shock and fire hazard.
Hot Materials
CAUTION
Welded materials are hot and can cause severe burns if handled improperly.
- Do not touch welded materials with bare hands.
- Do not touch TIG gun nozzle after welding until it has had time to cool down properly.
Sparks/Flying Debris
CAUTION
Welding creates hot sparks that can cause injury. Chipping slag creates flying debris.
- Wear protective gear at all times: ANSI-approved safety glasses or shield, welder’s mask
(helmet) and ear plugs to prevent spark injuries of your eyes, face, ears and hair.
Electromagnetic Field
CAUTION
- Electromagnetic fields can interfere with various electrical and electronic devices such
as pacemakers.
- Consult your doctor before using any electric arc welder or cutting device.
- Keep people with pacemakers away from your welding area when welding.
- Do not wrap cable around your body while welding.
- Wrap TIG gun cable and ground cable together whenever possible.
- Keep TIG gun cable and ground cables on the same side of your body.

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Shielding Gas Cylinders Can Explode
WARNING
High pressure cylinders can explode if damaged, so treat them carefully.
- Never expose cylinders to high heat, sparks, open flames, mechanical shocks or arcs.
- Do not touch the cylinder with TIG gun.
- Do not weld on the cylinder.
- Always secure cylinder upright to a cart or stationary object.
- Keep cylinders away from welding or electrical circuits.
- Use the proper regulators, gas hose and fittings for the specific application.
- Do not look into the valve when opening it.
- Use protective cylinder cap whenever possible.
1.5 Proper Care, Maintenance and Repair
DANGER .
- Always have power disconnected when working on internal components.
- Do not touch or handle PC board without being properly grounded with a wrist strap. Put PC board
in static proof bag prior to moving or shipping it.
- Do not put hands or fingers near moving parts such as fan.

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Description
The EWI series is a DC inverter ARC welder. This unit uses
1~Phase 220V/230V/240V, 50/60HZ AC power. A
16 amp time delay fuse or circuit breaker is
recommended. Sticks (electrodes) can weld carbon steel
and stainless steel.
Unpacking
1.1 Open cardboard box, bags or styrofoam packaging containing the welder and
accessories
1.2 Check that contents is as in the list below
ITEM QTY.
DC Inverter Arc Welder 1 unit
Welding cable with electrode holder 1 pc
Grounding cable with earth clamp 1 pc
Operator’s Manual 1 set
1.3 After unpacking unit
Inspect carefully for any damage that may have occurred during transit. Check for loose, missing, or
damaged parts. In case of shipping damage contact carrier immediately.

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Specifications and Dimension
Description Specification
Model EWI 160
Input power V 220 230 240
Frequency Hz 50/60 50/60 50/60
Rated input current A 30 30 29
Rated input capacity KVA 6.9 6.9 6.9
No-load voltage V 75 78 80
Rated working voltage V 26.4 26.4 26.4
MMA welding current A 20～160 20～160 20～160
Rated duty cycle % 20 20 20
Welding current（10min）
A
20%@160 20%@160 20%@160
10min/100% A 72 72 72
Efficiency η 85% 85% 85%
Power factor Cosφ 0.65 0.65 0.65
Insulation class H H H
Enclosure protection IP 21S 21S 21S
Cooling method Fan cooled Fan cooled Fan cooled
Dimension L×W×H cm 38×12×25.5 38×12×25.5 38×12×25.5
Weight kg 4.6 4.6 4.6

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Description Specification
Model EWI 200
Input power V 220 230 240
Frequency Hz 50/60 50/60 50/60
Rated input current A 40 40 38
Rated input capacity KVA 8.8 9.2 8.8
No-load voltage V 70 72 75
Rated working voltage V 28 28 28
MMA welding current A 20～200 20～200 20～200
Rated duty cycle % 20 20 20
Welding current（10min）
A
20%@200 20%@200 20%@200
10min/100% A 89 89 89
Efficiency η 85% 85% 85%
Power factor Cosφ 0.70 0.70 0.70
Insulation class H H H
Enclosure protection IP 21S 21S 21S
Cooling method Fan cooled Fan cooled Fan cooled
Dimension L×W×H cm 38×12×25.5 38×12×25.5 38×12×25.5
Weight kg 4.75 4.75 4.75

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Getting to Know your Welder
POWER INDICATOR
When the machine is turned on, the power indicator will be lit.
ALARM INDICATOR
When the thermal indictor is lit, it shows that the machine is overloaded and that the internal temperature
is too high. Welding output will turn off automatically, but the fan will still be working. When the internal
temperature is decreased, the overload light will turn off and the machine will be ready to weld.
WELDING CURRENT CONTROL
Welding current (amperage) control is placed on the front panel of machine.
WELDING CABLE
The welding cable is attached to electrode to complete the circuit, allowing the flow of current needed
to weld.
GROUNDING CABLE
The ground cable/clamp is attached to the workpiece to complete the circuit, allowing the flow of
current needed to weld.
Power Cord
Power Switch
Welding
cable
Power
Indicator
Welding
Current
control
Alarm
Indicator
Welding
Mode
Selector
Welding
Mode
Indicator
Grounding
cable

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POWER SWITCH
In the “OFF” position no power is being supplied.
In the “ON” position power is supplied to the mains transformer and control circuit.
POWER CORD
The power cord connects the welder to the 220/230/240 volt, 16 amp power supply mains socket
to supply power to the welder.

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Installation
1. Power requirement
AC single phase 220V/230V/240V, 50/60HZ mains supply fused with a 16 amp time delayed fuse
or circuit breaker is required.
WARNING
• Your EWI series DC Inverter Arc Welder is a class A product.
• EWI series DC Inverter Arc Welders adopt the drooping characteristic.
• High voltage danger from power source! Consult a qualified electrician for proper installation of
needed socket. This welder must be grounded while in use to protect the operator from electric shock.
• Do not remove grounding prong or alter the plug in any way. Do not use any adapters between the
welder’s power cord and the power source socket. Make sure the POWER switch is in OFF position
when connecting your welder’s power cord to a properly grounded 220V/230V/240Vac,
50/60Hz, single phase mains supply.
2. Extension cord
During normal use an extension cord should not be used. It is strongly recommended that an extension
cord should not be applied because of the voltage drop they produce. This voltage drop can affect the
performance of the welder. If you must use an extension cord it needs to be a #12 gauge cord at the
smallest.
- Do not use an extension cord over 7,5 m in length.
3. Setting up the work piece
3.1 Welding positions
There are two basic positions, for welding: Flat and Horizontal. Flat welding is generally easier, faster,
and allows better weld fusion. If possible, the work piece should be positioned so that the bead will run
on a flat surface.
3.2 Preparing the Joint
Before welding, ensure that the surface of work piece is free of dirt, rust, lime scale, oil or paint.
Otherwise, it will create brittle and porous weld. If the base metal pieces to be joined are thick or heavy,
it may be necessary to bevel the edges with an angle grinder. The correct groove angle should be
around 60 degrees.
Please see the following picture:

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Based on different welding position, there are different welding joints. Please observe the following
images for more explanation:
4. Ground clamp connection
Clear any dirt, rust, lime scale, oil or paint residues on the ground clamp. Make certain you have a
good solid ground connection. A poor connection of the ground clamp will waste power and heat.
Make sure the ground clamp touches the metal.

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5. Electrode
The welding electrode is a rod coated with a layer of flux. When welding, electrical current flows
between the electrode (rod) and the grounded metal (workpiece). The intense heat of the arc between
the rod and the grounded metal melts the electrode and the flux.
6. Selecting the proper electrode
There is no golden rule to determine the exact electrode or heat setting required for every particular
situation. The type and thickness of metal and the position of the workpiece rule the electrode type and
the amount of heat needed during welding process. Heavier and thicker metals require more
amperage. It is best to practice your welds on scrap metal which matches the metal you intend to work
with, in order to define correct heat setting as well as make appropriate electrode choice. Please
observe some following helpful troubleshooting tips to determine if you are using a correct electrode.
1. When electrode of proper size is used
a. The bead will lay smoothly over the workpiece without ragged edges
b. The base metal puddle will be as deep as the bead that rises above it
c. The welding operation will make a crackling sound similar to the sound of eggs frying
2. When too thin electrode is used
a. The weld bead will be too high and irregular
b. The arc will be difficult to maintain
3. When too thick electrode is used
a. The arc will burn through thin metals
b. Occurrence of the weld bead undercutting
c. The bead will be flat and porous
d. Rod might get freezed or sticked to the workpiece
Note: Rate of travel over the workpiece also affects the weld. To ensure proper penetration and enough
rod deposit, the arc must be moved slowly and evenly along the weld seam.

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Operation
1. Setting the adequate amperage
Your welder is capable of welding with 2.5mm, 3.2mm and 4mm electrodes.
There is no golden rule that determines the exact amperage required for every particular situation. It is
best to practice your welds on scrap metal which matches the metals you intend to work with in order
to determine correct settings for your job. The electrode type and the thickness of the metal workpiece
define the amount of heat needed in the welding process. Heavier and thicker metals require more
current (amperage), whereas lighter and thinner metals require less current (amperage).
2. Welding techniques
The best way to teach yourself how to weld is with short periods of practice at regular intervals. All
practice welds should be done on scrap metal that can be discarded. Do not attempt to make any
repairs on valuable equipment until you are satisfied with yourself and your practice welds are of good
appearance and free of slag or gas inclusions.
2.1 Holding the electrode
The best way to grip the electrode holder is the way that feels most comfortable to you. To position the
electrode on a workpiece when striking the initial arc, it is necessary to hold the electrode perpendicular
to the workpiece. Once the arc is started the angle of the electrode in relation to the workpiece should
be between 10 and 30 degrees. This will allow good weld penetration, with minimal spatter.
2.2 Striking the arc
WARNING
EXPOSURE TO A WELDING ARC IS EXTREMELY HARMFUL TO THE EYES AND SKIN.
• Never strike an arc or begin welding until you have adequate protection.
• Wear flameproof welding gloves, heavy long-sleeved shirt, cuffless trousers, high-topped shoes and
a welding helmet or shield.
Scratch the work piece with the end of electrode to start arc and then raise it quickly to about 3 mm
gap between the rod and the workpiece. Please observe the following picture:
It is important that the gap is maintained during the welding process and it should be neither too wide
or too narrow. If it is too narrow, the rod will stick to the workpiece. If it is too wide, the arc will be

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extinguished. It takes a a lot of practice to maintain the gap. Beginners may usually get sticking or arc
extinguishing. When the rod sticks to the workpiece, gently rock it back and forth to separate it from
the workpiece. If you don't, the short circuit occurs, which leads to welder overload. A good arc is
accompanied by a crisp, cracking sound. The sound is similar to that made when frying eggs. To lay a
weld bead, only 2 movements are required; downwards and in direction of the weld to be laid, as
shown in the following picture:
2.3 Types of weld beads
The following paragraphs discuss the most commonly used arc welding beads.
The stringer bead is formed when electrode is traveling in a straight line while kept centered over the
weld joint.
The weave bead is used when you want to deposit metal over a wider space which wouldn't be possible
using a stringer bead (without transfer oscillation). It is made by weaving electrode from side to side
with slight hesitation at the end of each oscillation while moving it longitudinally. That is the best way
to improve weld penetration.

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2.4 Welding position
Flat position is the easiest of all welding positions and is most commonly used. It is best if you can
weld in the flat position if at all possible since good results are easier to achieve.
The horizontal positions is performed very much the same way as the flat weld except that the
angle is different such way that the electrode, and therefore the arc force, is directed more toward the
metal above the weld joint. This more direct angle helps prevent the weld puddle from running
downwards while still allowing slow enough travel speed to achieve good penetration. A good starting
point for your electrode angle is about 30 degrees DOWN from being perpendicular to the workpiece.
2.5 Judging a good weld bead
When the trick of establishing and holding an arc has been learned, the next step is to lear how to run
a good bead. The first attempts in practice will probably fall short of acceptable results. Arc too long
will be held or the travel speed will vary from slow to fast. (Please observe the following picture).
A. Weld speed is too fast.
B. Weld speed is too slow.

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C. Arc is too long.
D. Ideal weld.
A solid weld bead requires the electrode to be moved slowly and steadily along the weld seam. Moving
the electrode rapidly or erratically will prevent proper fusion or create a lumpy, uneven bead. To
prevent ELECTRIC SHOCK, do not perform any welding while standing, kneeling, or lying directly on
the grounded workpiece.
2.6 Finishing the bead
As the coating on the outside of the electrode burns off, it forms an envelope of protective gasses
around the weld. This prevents air from reaching the molten metal and creating an undesirable chemical
reaction. However, coating burning forms slag. The slag formation appears as an accumulation of dirty
metal scale on the finished weld. Slag should be removed by striking the weld with a chipping hammer.
2.7 Working with cellulose electrode
When working with cellulose electrode it is necessary to set higher open circuit voltage. The EWI 200
welder has a special working mode for cellulose electrodes.
Switch welding mode selector to CELL. The green LED, along with the symbol will be lit. Before you
start working, check the polarity of the welding cable. Welding unit is now ready for cellulose electrode
use.
3. LIFT TIG method
3.1 Accessory
Switch off the welder. Remove mains plug from the wall socket. Switch welding mode selector to LIFT
TIG. The green LED, along with the symbol will be lit.
Connect the ground cable to the positive dinse socket and screw it tight. Connecct the end of the ground
cable (earth clamp) to the workpiece. Connect the torch cable to the negative dinse socket and screw
it in clockwise direction. Tighten the torch gas hose adaptor which connects the shielding gas cylinder.
Insert the mains plug into the mains socket.
3.2 The torch pilot arc
Warning! Turn on the welder. Welding torch's tungsten electrode is already charged. The tungsten
electrode should not touch anything. This series TIG welding machine needs contact striking to produce
the arc.

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How to strike the arc method is explained in the following step:
A. Open the built-in TIG torch gas valve. Place the gas nozzle so that the tungsten electrode and the
workpiece are separated 2~3mm.
B. Slowly lift the welding torch to cause the tungsten electrode to get into contact with a workpiece.
C. Lift the welding torch to the normal position to initiate the arc and start welding.

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Troubleshooting Chart
No. Symptom Possible Cause Solutions
1 The yellow
Indicator is lit
Mains voltage too high
(≥15%) Switch off the welder; Check the mains
supply; Turn on welder when power
restores to normal state.
Mains voltage too low
(≤15%)
Bad unit ventilation
leads to overheat
protection
Improve ventilation conditions.
Current temperature
too high
Welder automatically recovers when
the temperature falls down.
Over rated duty-cycle
used
Welder automatically recovers when
the temperature falls down.
2
The cooling fan
is not working
or turning very
slowly
Broken switch Replace the switch
Broken fan Replace or repair the fan
Wire broken or wire
falling off Check the connection
3
Poor weld
quality (refers to
TIG welding
only)
No, or insufficient gas
flow
Check shielding gas flow and adjust as
required
Incorrect ceramic
nozzle used
Select correct ceramic nozzle to match
tungsten electrode
Check condition of
tungsten electrode
Re-grind to shape or replace tungsten
electrode

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Spare Part List