250AMP

MIG /MMA

INVER

TER WELDER

Protect yourself and others by observing all safety information, warnings, and cautions. Failure to comply with instructions could result in personal injury and/or damage to product or property.

Please retain instructions for future reference!

ROSSWELDING RXT250EX

IMPORTANT

PLEASE

read all of the safety and operating instructions carefully before using this product. Please pay particular attention to all sections of this manual that carry warning symbols and notices.

WARNING!

THIS

is a Warning symbol. This symbol is used throughout the manual whenever there is a risk of personal injury. Ensure that these warnings are read and understood at all times.

CAUTION!

THIS

is a Caution symbol. This symbol is used throughout the user guide whenever there is a risk of damaging your product. Ensure that these warnings are read and understood at all times.

GENERAL DESCRIPTION

A general purpose MIG /MMA welder for general purpose workshop use. The power source is an

IGBT inverter.

PRODUCT SPECIFICATION

Rated No-load Voltage

Maximum Input Current

Rated Input Current

MIG

Rated Output

Rated Duty Cycle

Output Range

MMA (STICK)

Rated output

Rated Duty Cycle

Output Range

53V , < 15 DC (VRD mode)

46 Amp

27.2 Amp

250 Amp

35%

30-250 Amp

225 Amp

35%

20-225 Amp

WARNING! SAFETY INSTRUCTIONS

The user of this welder is responsible for his own and the safety of others. It is most important to read, learn and respect the rules in this user guide.

When using this welder, basic safety precautions, including the following, should be followed to reduce the risk of fire, electric shock and personal injury. Make sure that you have read all of these instructions before using this welder. Keep this booklet in a safe place for future reference.

Persons who are not familiar with this booklet should not use the welder.

TRAINING

The operator should be properly trained to use the welding machine safely and should be informed about the risks relating to arc welding procedures. This manual does not attempt to cover welding technique. Training should be sought from qualified/experienced personnel on this aspect especially for any welds requiring high integrity for safety.

SERIOUS FIRE RISK

The welding process produces sparks, droplets of fused metal, metal projectiles and fumes. This constitutes a serious fire risk. Make sure that the area around the work piece is clear of all inflammable materials. It is advisable to have a fire extinguisher to hand.

WORK AREA

Ensure a clear work area with unrestricted movement for the operator. Always maintain easy access to the On/Off switch and the mains supply.

THE WORK PIECE

The work piece will remain at a high temperature for a relatively long period. Do not touch the weld or the work piece unless you are wearing welding gloves. Always use pliers or tongs. Never touch the welded material with bare hands until it has been allowed to cool.

WELDING SURFACES

Do not weld on containers or pipes that hold, or have held, flammable liquids or combustible gases.

Do not weld coated, painted or varnished surfaces as the coatings may ignite and or can give off dangerous fumes.

VENTILATE THE WORK AREA

Arc welding (especially using fluxed core wire) emits fumes which can be dangerous. Make sure that the work area is well ventilated.

AVOID ELECTRICAL CONTACT

Use adequate electrical insulation with regard to the electrode, the work piece and any accessible) earthed metal parts in the vicinity. Avoid direct contact with the welding circuit. The no load voltage between the earth clamp and the torch can be dangerous under certain circumstances.

FOR ADDITIONAL PROTECTION FROM ELECTRIC SHOCK

It is recommended that this tool be used in conjunction with a residual current device (RCD) with a rated residual current of 30mA or less.

CONSIDER WORK AREA ENVIRONMENT

Do not expose the welder to rain. Do not use it in damp, or wet locations. Keep the work area well lit.

SAFETY INSTRUCTIONS … cont

DRESS PROPERLY

Use protective gloves and fire resistant protective clothing when using the welder. Avoid exposing skin to the ultraviolet rays produced by the arc.

ALWAYS USE THE WELDING MASK

Under no circumstances should the welder be operated unless the welding mask is protecting the eyes and face. There is a serious risk of eye damage if the mask is not used. The sparks and metal projectiles can cause serious damage to the eyes and face. The light radiation produced by the arc can cause damage to eyesight and burns on the skin. Never remove the welding mask whilst welding. Move the torch away from the work piece and release the trigger switch before removing the welding mask.

SAFETY GLASSES

After welding use safety glasses when brushing, chipping grinding the slag from the weld.

OTHER PERSONS

Ensure that other persons are screened from the welding arc and are at least 15 metres away from the work piece. Always ensure that the welding arc is screened from onlookers, or people just passing by. Use screens if necessary, or non reflecting curtains.

KEEP CHILDREN AND ANIMALS AWAY

Do not let children or animals have access to the welding equipment or to the work area.

SWITCHING OFF

When you have finished welding switch off the welder. Do not put the torch down with the welder switch On and with the wire fitted. When leaving the welder unattended, move the On/Off switch to the Off position and disconnect the welder from the mains supply. Do not leave hot material unattended after welding.

WELDING CABLES

Keep the welding cables, earth clamp and torch in good condition. Failure to can result in poor welding quality and could be dangerous in structural situations.

CHECK DAMAGED PARTS

Before further use of the welder, any part that is damaged should be carefully checked to determine that it will operate properly and perform its intended function. Check for breakage of parts and any other conditions that may affect its operation. Any part that is damaged should be properly repaired, or replaced, by an authorised service centre.

IMPROPER USE

Do not use this welder for pipe thawing.

HANDLING

Ensure the handle is correctly fitted and always use safe lifting practices when lifting.

CAUTION!

- VENTILATE THE WELDER

THERE

must always be a sufficient air passage around the welder to allow for the cooling

of the transformer. If the cooling process is obstructed the welder will overheat and the overload cut out protector will activate and cut off the welding current. If the overload cut out protector activates leave the welder for at least 15 minutes to cool down before further use.

ADDITIONAL PRECAUTIONS

WELDING OPERATIONS:

In environments with increased risk of electric shock;

In confined spaces; In the presence of flammable or explosive materials;

MUST BE evaluated in advance by an “expert supervisor” and must always be carried out in the presence of other people trained to intervene in emergencies.

POSITION and HANDLING

Position the welding machine on a horizontal surface that is able to support the weight: otherwise (e.g. inclined or uneven floors etc.) there is danger of overturning.

The welder MUST NOT be supported by the operator (e.g using belts).

The operator MUST NOT BE ALLOWED to weld in raised positions unless safety platforms are used.

VOLTAGE BETWEEN ELECTRODE HOLDERS OR TORCHES:

Working with more than one welding machine on a single piece or on pieces that are connected may generate a dangerous accumulation of no-load voltage between two different electrode holders or torches, the value of which may reach double the allowed limit.

IMPROPER USE:

It is hazardous to use the welding machine for any work other than that for which it was designed. Example do not use this welder for pipe thawing. The safety guards and moving parts of the covering of the welding machine and of the wire feeder should be in their proper positions before connecting the welding machine to the power supply.

WARNING!

Any manual operation carried out on the moving parts of the wire feeder, for example:

Replacing rollers and/or the wire guide; Inserting wire in the rollers; Loading the wire reel;

Cleaning the rollers and the area underneath them.

Should be carried out with the welding machine switched off and disconnected from the power supply outlet . Never lift the welding machine when connected to the mains supply.

WARNING!

When using this welder, provide adequate ventilation or facilities for the removal of welding fumes near the arc; a systematic approach is needed in evaluating the exposure limits for the welding fumes, which will depend on their composition, concentration and the length of the exposure itself. Do not operate on materials cleaned with chlorinated solvents or near such substances. Remove all flammable materials (e.g. wood, paper, rags etc.) from the working area.

WARNING!

Do not weld on containers or piping that contains or has contained flammable liquids or gaseous products. Do not weld on containers under pressure.

WARNING!

This welding machine complies with the requirements of the technical standard for the product for use only and exclusively in industrial environments and for professional purposes. It is not guaranteed to meet electromagnetic compatibility requirements in the home.

WARNING!

When using this welder, always use a welding helmet . Use special fire resistant protective clothing and do not allow the skin to be exposed to the ultra violet and infrared rays produced by the arc; other people in the vicinity of the arc should be protected by shields of non-reflecting curtains.

WARNING! Do not use in rain or store in locations affected by rain.

WARNING SYMBOLS

The following warning symbols are to remind you of the safety precautions you should take when using the welder.

WARNING!

Read this User Guide carefully before using the welder and keep it in a safe place for future reference.

WARNING!

When using this welder, avoid direct contact with the welding circuit. The noload voltage supplied by the welding machine can be dangerous in certain circumstances.

THE RATING PLATE

The rating plate is fitted to the welder and displays the following symbols and information.

X

I1max

I1eff

U1

Mains supply, single phase

A.C. 50/60Hz

Welding Modes

MIG/MMA

Duty Cycle

Maximum Input current

Rated input current

Rated input voltage

I2

U2

U0

IP21S

Regulatory compliance mark.

Single phase input, frequency conversion, rectifier

Welding Current

Welding Voltage

Open circuit output voltage

Protection class

KNOW YOUR WELDER

3

2

1

13

12

11

4

5

6

7

8

9

14

15

10

16

REAR PANEL

25

24

Wire feed side

17 18

19

20

21

22

23

[1] Mode switch MIG /MMA

[2] GREEN Power lamp

[3] ORANGE Alarm/ Temperature lamp

[4] GREEN VRD indicator (MMA mode)

[5] 2 STEP / 4 STEP selector switch (MIG

MODE)

[6] Manual Wire feed. (MIG MODE)

[7] Welding power (MIG MODE)

[8] Wire feed speed control (MIG MODE)

[9] Negative output terminal.

[10] Tool Draw

11 Euro torch connector

12 Positive output terminal

[13] Welding current control (MMA MODE)

[14] Mains input

[15] Power switch

[16] Gas input.

[17] ARC Characteristics

[18] Burn Back control

[19] Positive output terminal

[20] MIG welding polarity selection cable.

[21] Tension screw

[22] Wire feed roller

[23] Guide tube

[24] Reel Holder

[25] Negative output terminal.

MIG MODE

LOADING THE WIRE

• Select MIG mode with the mode switch on the front panel.

• Set the

2 STEP / 4 STEP selector switch [5] to 2 Touch

• Fit the torch to the euro fitting [11] and firmly tighten.

• Open the side cover of the unit

• Remove the knob from the wire reel holder [24] and fit the wire spool onto the wire reel so that the wire will exit the spool from the bottom

• Refit the knob [24].

• Release the tension screw [21] and open the upper roller arm.

• Without letting the wire un-spool, cut the end of the wire of cleanly leaving no kinks the feed about 30cm of the wire through the guide tube and into the wire liner by hand.

• The wire feed roller [22] has two different size groves. Check that the wire is aligned with the correct size grove in the wire feed roller for the type of wire and then careful close the upper roller and tension screw. If necessary remove the wire feed roller and turn it over to access the other grove and refit.

At the end of the torch

• Twist the nozzle clockwise and pull to remove.

• Unscrew the contact tip counterclockwise and remove. Check that the correct tip size is being used for the wire being fitted.

• Lay the torch sheath out in a straight line so that the wire move through it easily

WARNING!

The following steps require applying power to the welder. Do not touch anything with the torch or wire as it may result in accidental arcing.

• Plug the power cord [14] into its electrical outlet, set the wire feed speed control [8] mid way and turn the welder ON [15].

• Press the wire feed button [6] or lift the torch handle and continue pressing the trigger until the wire feeds through the end of the torch about 50mm

Note: If the wire does not feed through, view the wire feed unit and see if the wire is being pushed. If it is not, turn the welder OFF and add more tension to the wire feed adjusting spring and try again.

• Once the wire is exposed, release the wire feed button [6] or the trigger

• Slide the contact tip over the wire and screw it into torch handle

• Replace the nozzle and cut off any excess wire over 10mm

POLARITY SELECTION

A B

• The correct polarity must be set for the type of welding.

When using solid wire in conjunction with welding gas, connect the torch to the positive terminal and the earth clamp to the negative. See diagram A.

When using flux cored wire (gasless) connect the negative terminal to the welding torch and the earth clamp to the positive. see diagram B.

CAUTION!

Check that the dinse terminals are tight before commencing to weld to prevent burning

To commence the welding process proceed as follows.

• Make sure that the earth clamp is firmly connected to the Work piece.

WARNING! Ensure that you have your protective clothes, gloves and welding helmet

correctly fitted before welding. Do not start welding before your eyes are properly protected by the welding helmet.

• Turn the welder switched ON and the welding gas if applicable.

You are now ready to execute the weld.

• Select the required welding voltage [7] setting weld for the job at hand.

• Bring the wire into close proximity of the required weld start position. Keep the tip approximately 10-15 mm away from the work piece and squeeze the trigger on the torch to commence welding.

• Adjust the wire feed [8] rate to obtain the optimum weld

2 STEP / 4 STEP

The 2 STEP /4 STEP switch [5] controls how the machine reacts to the trigger switch on the welding torch.

2 STEP mode

• Squeeze the trigger to start welding and release it to stop.

4 STEP mode

• Squeeze the trigger and release to start welding. To Stop, Squeeze the trigger and release again

THERMOSTATIC PROTECTION

This welder is automatically protected from overheating by a thermal overload cut out protector. If the transformer overheats the overload cut out protector will activate and cut off. The amber light will illuminate to show that the cut out has operated.

After cooling the protector will reconnect the supply circuit and the welder will be ready for further use.

NOTE: If the duty cycle of the machine is exceeded the thermostatic protection will activate.

There are no user serviceable parts inside the welder. Refer to qualified service personnel if any internal maintenance is required.

WARNING!

Before starting any cleaning, or maintenance procedures on the welding machine, make sure that it is switched Off and disconnected from the mains supply.

MAINTENANCE CHECKS

TORCH

Do not put the torch or its cable on hot work pieces; this would cause the insulating materials to melt, making the torch unusable.

Every time the wire reel is changed, clean out the wire-guide and check the wire liner for build up of dust and other contaminants. This increases friction and can lead to erratic wire feed and jamming. Replace when necessary.

Daily: Check the wear and correct assembly of the consumable parts at the end of the torch; swan neck, nozzle, contact tip. Replace when necessary.

WIRE FEEDER

Make frequent checks on the state of wear of the wire feed rollers, regularly remove the metal dust deposited in the feeder area (rollers and wire-guide in-feed and out- feed)

OTHER

Make sure that the earth clamp is kept clean and in good working order.

Keep the cooling vents clear and clean the outer casing with a soft cloth.

GAS BOTTLE AND REGULATOR

For gas shield welding connect the output of the regulator to the barb at the rear of the unit and secure.

Welding gas

Eg.

Co2 or Co2/ Argon

WARNING!

- Secure the gas bottle

MMA (ARC) WELDING

Warning ! For MMA (ARC) welding.

This unit is fitted with a Voltage Reduction Device (VRD).

The VRD lamp on the front panel is ILLUMINATED when operation in reduced voltage mode. Then this lamp is OFF indicates that the output voltage may not be reduced.

VRD (MMA mode)

The VRD is an addition safety feature which reduces the open circuit voltage at the output terminal when then the unit is not welding.

Note:

This feature can not be turned OFF.

• Select MMA mode on the mode selection switch [1].

• Connect the

Negative (-) output terminal [9] to the earth clamp lead.

• Connect the earth clamp to the job.

• Connect the Positive (+) output terminal [12] to the electrode holder.

Note

the electrode holder and cable is not supplied and must be purchased separately.

• Turn the power on [15]

• Select the desired welding current using the welding current control [13]

CAUTION!

When fitting the welding leads to the unit, twist the plugs clockwise and ensure that they are tight in the sockets. Loose connectors will overheat, damage the unit and void warranty.

Welding gas

Eg.

Co2 or Co2/ Argon

ARC WELDING PROCEDURE

Before commencing, make sure that your hand held welding mask or welding helmet is in position to protect your eyes. It is also advisable to wear gloves and clothing, which cover the hands and arms to prevent flash burns.

Striking Arc. This is done by bringing the electrode into contact with the work piece using a light tapping action and withdrawing to create a gap of (1.5 mm – 3.00 mm.).

Maintaining Arc. Having created an arc, all that is necessary to maintain it is to proceed steadily in one direction keeping the gap between the electrode and the work piece constant. The electric current will flow through the electrode, across the arc gap, and in doing so will melt the electrode core wire and protective flux. The electrode length will gradually decrease as the metal is transferred to the work piece under a protective slag formed by the flux. This slag can then be removed when cooled by lightly tapping with a pointed tool or a welders chipping hammer.

To stop welding, all that is required is to withdraw the electrode from the work piece - thus breaking the circuit. Be careful with the end of the electrode, as it will be hot! Provided the current setting is correct, the surface of the work piece will also melt by the intensity of the electric arc. A degree of

“penetration” is thereby obtained and a complete “fusion” of the work piece and the deposited electrodes met

Selection of electrode. There is no hard and fast rule by which a particular gauge of electrode is selected. Usually this is determined by, the type of weld required and the thickness of the work piece. E.g. a butt weld in (1.5mm.) sheet metal can be done by a 1.6mm or 2.5mm electrode, the difference being that the 2.5mm electrode will do the job quicker. The table below Gives guidance as to which electrode is most suitable according to the material thickness. This table is only a guide, and values given are an indication only.

Tip! Keep the welding current as low as possible for the job at hand to maintain the best duty cycle from you welding machine, prevent the flux from burning and make removal of slag easier.

Amperage Selection Guide

Rod Size Welding Current

1.6mm

2.0mm

40 - 50 Amps

50 - 75 Amps

2.5mm

3.2mm

4.0mm

75 - 105 Amps

105 - 135 Amps

135 - 190 Amps

TROUBLESHOOTING GUIDE

No.

1

2

3

4

5

Breakdown

No current output

Bad wire feed

Porosity in weld

No wire feed

Analysis

No voltage input

Wrong Fuse or breaker rating

Thermal over load lamp lit

Low wire feed pressure

No back tension on reel

Wire is oxidised

Poor weld penetration Low input voltage

Bad connection

Solutions

Check the fuse and or circuit breaker

Replace with correct rating fuse or breaker

Allow the unit to cool

Tighten the wire tension adjustment nut

Check the wire spool clip

Replace wire spool.

Replace liner

Check that if input voltage is the same with rated voltage

Check grounding cable/ clamp, make sure of a good connection.

Contact tip worn

No gas ,little gas or wrong gas

Replace contact tip

Check all gas

Blockage of gas line Use compress air to clear the Blockage

Torch valve has been blocked

Bad gas and wire

Open the welding torch and check

Gas must be dry, use another type wire

Check by inspection Control wire broken or Faulty switch in the handle

Wire Control PCB faulty

Replace the PCB

Notes

WARRANTY

Our goods come with guarantees that cannot be excluded under the Australian Consumer Law.

You are entitled to a replacement or refund for a major failure and for compensation for any other reasonably foreseeable loss or damage. You are also entitled to have the goods repaired or replaced if the goods fail to be of acceptable quality and the failure does not amount to a major failure.

This product is guaranteed against faulty materials and workmanship for 12 months from the date of purchase.

Please retain your receipt as proof of purchase.

This warranty does not cover defects caused by or resulting from:

(a) misuse, abuse or neglect;

(b) trade, professional or hire use;

(c) repairs attempted by anyone other than our authorised repair centres; or

(d) damage caused by foreign objects, substances or accident.

WARRANTY EXCLUSIONS

Wear parts or service related parts required when performing normal and regular maintenance of this product are not covered by warranty unless it is found to be defective by an Authorised

Service Centre.

Consumable items such as swan necks, nozzles, contacts tips, wire liners etc are not covered by warranty.

Distributed in Australia by WHITE INTERNATIONAL

PO Box 304 Milperra LPO, NSW, Australia, 2214

Inquiries phone 1800 251 338

THE WHITE INTERNATIONAL policy is one of continuous improvement and the company reserves the right to the alter designs, colours and specifications without notice.

For information on all ROSS products please visit: www.rosstools.com.au

The ROSS logo and Bull device are trademarks of J.W. Ross Pty Ltd.