General
General
Welding torches with integrated wire drives are suitable for MIG/MAG manual welding with long hosepacks, particularly when soft filler metals are being used. Two geared precision rollers ensure power is transmitted over a large area. This provides outstanding wirefeed characteristics, even when using very soft aluminium or CuSi wire electrodes and very long hosepacks.
The welding torches are particularly robust and reliable, with an ergonomic grip, ball joint and perfect weight distribution for fatigue-free working.
Available as gas-cooled and water-cooled versions and in conjunction with the available Multilock torch necks, the welding torches can be used in an extremely wide range of applications. They are ideal for manual batch and single-piece production as well as for jobs in the workshop.
General
Welding torches with integrated wire drives are suitable for MIG/MAG manual welding with long hosepacks, particularly when soft filler metals are being used. Two geared precision rollers ensure power is transmitted over a large area. This provides outstanding wirefeed characteristics, even when using very soft aluminium or CuSi wire electrodes and very long hosepacks.
The welding torches are particularly robust and reliable, with an ergonomic grip, ball joint and perfect weight distribution for fatigue-free working.
Available as gas-cooled and water-cooled versions and in conjunction with the available Multilock torch necks, the welding torches can be used in an extremely wide range of applications. They are ideal for manual batch and single-piece production as well as for jobs in the workshop.
Functions of the torch trigger
The torch trigger on the welding torch has two switching positions.
- LED illuminated
- LED goes out
- Welding start-up
Up/Down-function
The Up/Down torch has the following functions:
- Changes the welding power in Synergic operation via the Up/Down buttons
- Error display:
- all the LEDs light up red if there is a system fault
- all the LEDs flash red if there is a data communication fault
- Self-test during the run-up sequence:
- all LEDs light up briefly one after the other
JobMaster-function
The JobMaster welding torch has the following functions:
- The desired welding parameter on the power source can be selected using the arrow buttons
- The selected welding parameter can be changed using the +/- buttons
- The display shows the current welding parameter and value
Proper use
The MIG/MAG manual welding torch is intended solely for MIG/MAG welding in manual applications.
Any use above and beyond this purpose is deemed improper. The manufacturer shall not be held liable for any damage arising from such usage.
- Carefully reading and following all the instructions given in the operating instructions
- Performing all stipulated inspection and maintenance work.
Safety
Warning notices on the device
The welding torch is fitted with safety symbols and a rating plate. The rating plate and safety symbols must not be removed or painted over. The symbols warn against operating the equipment incorrectly, as this may result in serious injury and damage.
Rating plate with safety symbols
Warning of moving parts
- These Operating Instructions
- The enclosed "Safety rules" document
- All the Operating Instructions for the system components, especially the safety rules
- Welders must be sufficiently qualified
- Suitable protective equipment must be used
- All persons not involved must be kept at a safe distance from the welding torch and the welding process
Do not dispose of used devices with domestic waste. Dispose of them according to the safety rules.
- Cogs
- Feed rollers
- Wirespools and wire electrodes
Do not reach into the rotating feed rollers of the wire drive or into rotating drive components.
The cover of the welding torch may only be opened while maintenance or repair work is being carried out.
During operation- Ensure that the cover is closed.
- Keep the cover closed.
Warning notices on the device
The welding torch is fitted with safety symbols and a rating plate. The rating plate and safety symbols must not be removed or painted over. The symbols warn against operating the equipment incorrectly, as this may result in serious injury and damage.
Rating plate with safety symbols
Warning of moving parts
- These Operating Instructions
- The enclosed "Safety rules" document
- All the Operating Instructions for the system components, especially the safety rules
- Welders must be sufficiently qualified
- Suitable protective equipment must be used
- All persons not involved must be kept at a safe distance from the welding torch and the welding process
Do not dispose of used devices with domestic waste. Dispose of them according to the safety rules.
- Cogs
- Feed rollers
- Wirespools and wire electrodes
Do not reach into the rotating feed rollers of the wire drive or into rotating drive components.
The cover of the welding torch may only be opened while maintenance or repair work is being carried out.
During operation- Ensure that the cover is closed.
- Keep the cover closed.
Safety
WARNING!
Danger from incorrect operation and work that is not carried out properly.
This can result in serious personal injury and damage to property.
All the work and functions described in this document must only be carried out by technically trained and qualified personnel.
Read and understand this document in full.
Read and understand all safety rules and user documentation for this device and all system components.
WARNING!
Danger from electric current.
This can result in serious personal injury and damage to property.
Before starting work, switch off all the devices and components involved and disconnect them from the grid.
Secure all the devices and components involved to prevent unintentional restarting.
After opening the device, use a suitable measuring instrument to check that electrically charged components (such as capacitors) have been discharged.
WARNING!
Danger from electric current due to defective system components and incorrect operation.
This can result in serious injury and damage to property.
All cables, lines and hosepacks must be properly connected, undamaged, correctly insulated and adequately dimensioned at all times.
CAUTION!
Risk of burns from hot welding torch components and hot coolant.
This can result in scalding.
Before commencing any of the work described in this document, allow all welding torch components and the coolant to cool to room temperature (+25°C, +77°F).
CAUTION!
Danger from operation of water-cooled welding torches without coolant.
This can result in damage to property.
Never operate a water-cooled welding torch without coolant.
During welding, ensure that the coolant is circulating correctly – this will be the case if a regular return flow of coolant can be seen in the coolant container of the cooling unit.
The manufacturer will not be liable for any damages due to non-observance of the above mentioned points, and all claims against the warranty shall be void.
CAUTION!
Risk of coolant escaping.
This can result in injury and damage to property.
Seal the coolant hoses on water-cooled welding torches with the plastic stoppers fitted to them if the hoses are detached from the cooling unit or other system components.
CAUTION!
Risk of injury from moving parts.
This can result in injury and damage to property.
Close the cover over the feed rollers before using the welding torch.
Start-up
MTG d, MTW d - Fitting wearing parts to the torch body
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2
3
| ** | Screw on and tighten the gas nozzle as far as it will go |
MTG d, MTW d - Fitting wearing parts to the torch body
1
2
3
| ** | Screw on and tighten the gas nozzle as far as it will go |
Note regarding the inner liner with gas-cooled welding torches
NOTE!
If a plastic inner liner is used in the torch body of a gas-cooled welding torch, reduce the power figure shown in the technical data by 30%.
To operate gas-cooled welding torches at maximum power, use a steel inner liner in the torch body.
Checking the clamping nipple
* Check the clamping nipple before commissioning and whenever the inner liner is changed. To do so, carry out a visual inspection:
- Left: brass clamping nipple with seal ring. You cannot see through the seal ring.
- Right: silver clamping nipple with see-through bushing
NOTE!
Incorrect or defective clamping nipple in push applications
Causes gas loss and poor weld properties
use brass clamping nipples to minimise gas loss
check that the seal ring is intact
NOTE!
Incorrect clamping nipple in push-pull applications
Tangled wire and increased abrasion in the inner liner when using a clamping nipple with seal ring
use silver clamping nipple to facilitate wirefeeding
Inserting a steel inner liner into the torch body
1
2
* Use the cutting pipe of the welding torch
Inserting a plastic inner liner into the torch body
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2
* Use the cutting pipe of the welding torch
Fitting wearing parts inside the hosepack
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10
| * | Push in infeed nozzle as far as it will go |
Fitting the inner liner inside the hosepack
NOTE!
Ensure that the hosepack is straight when fitting the inner liner, otherwise the liner might not be inserted correctly.
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2
3
4
| * | Insert inner liner as far as it will go into the infeed nozzle (1) |
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6
| ** | Steel inner liner |
| *** | Plastic inner liner |
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8
| **** | Screw the cap onto the inner liner as far as it will go. The inner liner must be visible through the hole in the cap. |
9
NOTE!
Steel inner liners with an outer diameter of less than 1 mm (0.039 in.) cannot be screwed into the welding torch - the specified tightening torque therefore does not apply to these liners.
All other inner liners must be screwed into the welding torch and tightened to the specified tightening torque.
10
Attaching the torch body
CAUTION!
Risk of damage to the welding torch.
Always tighten the union nut on the torch body as far as it will go.
NOTE!
Before fitting a torch body, ensure that the interface between the torch body and the hosepack is clean and undamaged.
NOTE!
In the case of water-cooled welding torches, increased resistance may arise when tightening the union nut due to the construction of the welding torch.
This is normal. Always tighten the union nut on the torch body as far as it will go.
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2
NOTE!
The torch body is in the 0° position when the dowel pin (1) on the hosepack engages in the locating hole (2) in the torch body.
3
| * | Ensure that the union nut is tightened as far as it will go. |
Connecting the welding torch to the wirefeeder
1
Connecting the welding torch
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2
| * | Only if the optional coolant connections are fitted in the cooling unit and when using a water-cooled welding torch. Always connect the coolant hoses according to their colour coding. |
3
Threading the wire electrode
CAUTION!
Risk of injury and damage from the welding current and accidental ignition of an arc.
Before starting work, disconnect the ground earth connection between the welding system and the workpiece.
CAUTION!
Risk of damage to the welding torch from sharp end of wire electrode.
Deburr the end of the wire electrode well before threading in.
CAUTION!
Risk of injury due to springiness of spooled wire electrode.
When inserting the wire electrode into the 4-roller drive of the wirefeeder, hold the end of the wire electrode firmly to avoid injuries caused by the wire springing back.
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2
CAUTION!
Risk of injury and damage from wire electrode emerging.
While working:
Hold the welding torch with the end directed away from the face and body
Wear suitable protective goggles
Do not point the welding torch at people
Make sure that the wire electrode does not touch any conductive or earthed parts (e.g. housing)
NOTE!
Before feeding in the wire electrode, lay out the hosepack in a straight line as shown below.
Maximum permitted feeder inching speed = 10 m/s.
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4
5
Setting the contact pressure
| * | Use the values shown on the illustration on the inside of the cover as standard values when setting the contact pressure. |
NOTE!
The contact pressure is set as follows:
Turn screw clockwise = reduce the contact pressure,
maximum load moment = gently as far as stop - turn the screw until the contact pressure indicator is in the 'min' position
Turn screw anti-clockwise = increase the contact pressure,
maximum load moment = 0.4 Nm - turn the screw until the contact pressure indicator is in the 'max' position
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2
3
Changing the torch neck, rotating the torch neck
Changing the torch body
CAUTION!
Risk of burns from hot coolant and hot torch body.
Before carrying out any work, allow the coolant and torch body to cool to room temperature (+25 °C, +77 °F).
NOTE!
Some coolant will always remain in the torch body.
Only remove the torch body with the gas nozzle pointing downwards.
NOTE!
Before fitting a torch body, ensure that the interface between the torch body and the hosepack is clean and undamaged.
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2
NOTE!
The torch body is in the 0° position when the dowel pin (1) on the hosepack engages in the locating hole (2) in the torch body.
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4
| * | Ensure that the union nut is tightened as far as it will go. |
Changing the torch body
CAUTION!
Risk of burns from hot coolant and hot torch body.
Before carrying out any work, allow the coolant and torch body to cool to room temperature (+25 °C, +77 °F).
NOTE!
Some coolant will always remain in the torch body.
Only remove the torch body with the gas nozzle pointing downwards.
NOTE!
Before fitting a torch body, ensure that the interface between the torch body and the hosepack is clean and undamaged.
1
2
NOTE!
The torch body is in the 0° position when the dowel pin (1) on the hosepack engages in the locating hole (2) in the torch body.
3
4
| * | Ensure that the union nut is tightened as far as it will go. |
Rotating the torch body
CAUTION!
Risk of burns from hot coolant and hot torch body.
Before carrying out any work, allow the coolant and torch body to cool to room temperature (+25 °C, +77 °F).
1
2
3
4
* Ensure that the union nut is tightened as far as it will go.
Care, maintenance and disposal
General
Regular preventive maintenance of the welding torch is essential if trouble-free operation is to be ensured. The welding torch is subjected to high temperatures and heavy soiling. The welding torch therefore requires more frequent maintenance than other components in the welding system.
CAUTION!
Risk of damage from improper handling of the welding torch.
This can result in severe damage to property.
Do not strike the welding torch on hard objects.
Avoid scoring and scratches on the contact tip.
Do not bend the torch body under any circumstances.
General
Regular preventive maintenance of the welding torch is essential if trouble-free operation is to be ensured. The welding torch is subjected to high temperatures and heavy soiling. The welding torch therefore requires more frequent maintenance than other components in the welding system.
CAUTION!
Risk of damage from improper handling of the welding torch.
This can result in severe damage to property.
Do not strike the welding torch on hard objects.
Avoid scoring and scratches on the contact tip.
Do not bend the torch body under any circumstances.
Maintenance at every start-up
- Check wearing parts
- replace faulty wearing parts
- Remove welding spatter from gas nozzle
1
2
| * | Check the gas nozzle, spatter guard and insulation for damage and replace any damaged components. |
- Also at every start-up when using water-cooled welding torches:
- check all coolant connections for tightness (no leaks)
- check that the coolant can flow unhindered
Every time the wirespool/basket-type spool is changed
- Clean wirefeeding hose with reduced compressed air
- Recommended: replace the inner liner. Clean the wearing parts before fitting the new inner liner
1
2
Recognising faulty wearing parts
- Insulating parts
- Burned-off outside edges, notches
- Nozzle fittings
- Burned-off outside edges, notches
- Heavily covered in welding spatter
- Spatter guard
- Burned-off outside edges, notches
- Contact tips
- Worn-out (oval) wire entry and wire exit holes
- Heavily covered in welding spatter
- Penetration on the tip of the contact tip
- Gas nozzles
- Heavily covered in welding spatter
- Burned-off outside edges
- Notches
Changing the wirefeeding nozzle
1Remove the wire electrode from the hosepack
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3
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Changing the infeed nozzle
1Remove the wire electrode from the hosepack
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3
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8
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10
| * | Push in infeed nozzle as far as it will go |
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| ** | Insert inner liner as far as it will go into the infeed nozzle (1) |
| *** | Screw the cap onto the inner liner as far as it will go. The inner liner must be visible through the hole in the cap. |
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16
NOTE!
Steel inner liners with an outer diameter of less than 1 mm (0.039 in.) cannot be screwed into the welding torch - the specified tightening torque therefore does not apply to these liners.
All other inner liners must be screwed into the welding torch and tightened to the specified tightening torque.
17
Changing the feed rollers
NOTE!
Always change feed rollers in pairs.
Only use feed rollers that match the wire diameter used and the wire alloy.
An overview of available feed rollers can be found in the Spare Parts Lists.
NOTE!
To tighten the new feed rollers, use the screws supplied with the new rollers.
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2
3
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| * | Turn the feed roller onto the drive until the splines on the feed roller engage in the grooves on the drive. |
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Troubleshooting
Troubleshooting
Troubleshooting
No welding current
Power source mains switch is on, indicators on the power source are lit up, shielding gas available
| Cause: | Grounding (earthing) connection is incorrect |
| Remedy: | Establish a proper grounding (earthing) connection |
| Cause: | There is a break in the current cable in the welding torch |
| Remedy: | Replace welding torch |
Nothing happens when the torch trigger is pressed
Power source mains switch is on, indicators on the power source are lit up
| Cause: | The FSC ('Fronius System Connector' central connector) is not plugged in properly |
| Remedy: | Push on the FSC as far as it will go |
| Cause: | Welding torch or welding torch control line is faulty |
| Remedy: | Replace welding torch |
| Cause: | Interconnecting hosepack faulty or not connected properly |
| Remedy: | Connect interconnecting hosepack properly Replace faulty interconnecting hosepack |
| Cause: | Faulty power source |
| Remedy: | Contact After-Sales Service |
No shielding gas
All other functions are OK
| Cause: | Gas cylinder is empty |
| Remedy: | Change the gas cylinder |
| Cause: | Gas pressure regulator is faulty |
| Remedy: | Replace gas pressure regulator |
| Cause: | The gas hose is not connected, or is damaged or kinked |
| Remedy: | Fit gas hose, lay out straight Replace faulty gas hose |
| Cause: | Welding torch is faulty |
| Remedy: | Replace welding torch |
| Cause: | Gas solenoid valve is faulty |
| Remedy: | Contact After-Sales Service (arrange for gas solenoid valve to be replaced) |
Poor weld properties
| Cause: | Incorrect welding parameters |
| Remedy: | Correct settings |
| Cause: | Poor grounding (earthing) connection |
| Remedy: | Ensure good contact to workpiece |
| Cause: | Too little or no shielding gas |
| Remedy: | Check the pressure regulator, gas hose, gas solenoid valve and welding torch shielding gas connection. On gas-cooled welding torches, inspect the gas seals, use a suitable inner liner |
| Cause: | Welding torch is leaking |
| Remedy: | Replace welding torch |
| Cause: | Contact tip is too large or worn out |
| Remedy: | Replace contact tip |
| Cause: | Wrong wire alloy or wrong wire diameter |
| Remedy: | Check wirespool/basket-type spool in use |
| Cause: | Wrong wire alloy or wrong wire diameter |
| Remedy: | Check weldability of the base material |
| Cause: | The shielding gas is not suitable for this wire alloy |
| Remedy: | Use the correct shielding gas |
| Cause: | Unfavourable welding conditions: shielding gas is contaminated (by moisture, air), inadequate gas shield (weld pool "boiling", draughts), contaminants in the workpiece (rust, paint, grease) |
| Remedy: | Optimise the welding conditions |
| Cause: | Shielding gas escaping at clamping nipple |
| Remedy: | Use the correct clamping nipple |
| Cause: | Clamping nipple seal ring defective, shielding gas escaping at clamping nipple |
| Remedy: | Replace clamping nipple to ensure a gas-tight seal |
| Cause: | Welding spatter in the gas nozzle |
| Remedy: | Remove welding spatter |
| Cause: | Turbulence caused by too high a rate of shielding gas flow |
| Remedy: | Reduce shielding gas flow rate, recommended: shielding gas flow rate (l/min) = wire diameter (mm) x 10 (e.g. 16 l/min for 1.6 mm wire electrode) |
| Cause: | Distance between the welding torch and the workpiece too great |
| Remedy: | Reduce the distance between the welding torch and the workpiece (approx. 10 - 15 mm / 0.39 - 0.59 in.) |
| Cause: | Tilt angle of the welding torch is too great |
| Remedy: | Reduce the tilt angle of the welding torch |
| Cause: | Wirefeed components do not match the diameter of the wire electrode/wire electrode material |
| Remedy: | Use the correct wirefeed components |
Poor wirefeeding
| Cause: | Depending on the system, brake force in wirefeeder or power source set too high |
| Remedy: | Reduce the brake force |
| Cause: | Hole in the contact tip is displaced |
| Remedy: | Change the contact tip |
| Cause: | The inner liner or wire-guide insert is defective |
| Remedy: | Check the inner liner and wire-guide insert for kinks, dirt, etc. Change the defective inner liner or wire-guide insert |
| Cause: | The feed rollers are not suitable for the wire electrode being used |
| Remedy: | Use suitable wirefeeder rollers |
| Cause: | Wirefeeder rollers have the wrong contact pressure |
| Remedy: | Optimise contact pressure |
| Cause: | The wirefeeder rollers are soiled or damaged |
| Remedy: | Clean or replace wirefeeder rollers |
| Cause: | Inner liner wrongly fitted or kinked |
| Remedy: | Replace inner liner |
| Cause: | The inner liner has been cut too short |
| Remedy: | Replace the inner liner and cut the new inner liner to the correct length |
| Cause: | Wire electrode worn due to excessive contact pressure on the wirefeeder rollers |
| Remedy: | Reduce contact pressure on the wirefeeder rollers |
| Cause: | Wire electrode contains impurities or is corroded |
| Remedy: | Use high-quality wire electrode with no impurities |
| Cause: | For steel inner liners: use of uncoated inner liner |
| Remedy: | Use a coated inner liner |
| Cause: | Clamping nipple in wire entry and wire exit area deformed (oval, knocked out), shielding gas escaping at clamping nipple |
| Remedy: | Replace clamping nipple to ensure a gas-tight seal |
The gas nozzle becomes very hot
| Cause: | No thermal dissipation as the gas nozzle is too loose |
| Remedy: | Screw on the gas nozzle as far as it will go |
The welding torch becomes very hot
| Cause: | Only on Multilock welding torches: torch neck union nut is loose |
| Remedy: | Tighten the union nut |
| Cause: | Welding torch operated above the maximum welding current |
| Remedy: | Reduce welding power or use a more powerful welding torch |
| Cause: | The specification of the welding torch is inadequate |
| Remedy: | Observe the duty cycle and loading limits |
| Cause: | Only on water-cooled systems: Inadequate coolant flow |
| Remedy: | Check coolant level, coolant flow, coolant contamination, the routing of the hosepack, etc. |
| Cause: | The tip of the welding torch is too close to the arc |
| Remedy: | Increase stick-out |
Contact tip has a short service life
| Cause: | Incorrect wirefeeder rollers |
| Remedy: | Use correct wirefeeder rollers |
| Cause: | Wire electrode worn due to excessive contact pressure on the wirefeeder rollers |
| Remedy: | Reduce contact pressure on the wirefeeder rollers |
| Cause: | Wire electrode contains impurities/is corroded |
| Remedy: | Use high-quality wire electrode with no impurities |
| Cause: | Uncoated wire electrode |
| Remedy: | Use wire electrode with suitable coating |
| Cause: | Wrong dimension of contact tip |
| Remedy: | Use a contact tip of the correct dimension |
| Cause: | Duty cycle of welding torch has been exceeded |
| Remedy: | Shorten the duty cycle or use a more powerful welding torch |
| Cause: | Contact tip has overheated. No thermal dissipation as the contact tip is too loose |
| Remedy: | Tighten the contact tip |
NOTE!When using CrNi, the contact tip may be subject to a higher degree of wear due to the nature of the surface of the CrNi wire electrode. | |
Torch trigger malfunction
| Cause: | Defective plug connection between welding torch and power source |
| Remedy: | Establish proper plug connections / have power source or welding torch serviced |
| Cause: | Build up of dirt between torch trigger and torch trigger housing |
| Remedy: | Clean away the dirt |
| Cause: | Control line is faulty |
| Remedy: | Contact After-Sales Service |
Weld seam porosity
| Cause: | Spatter build-up in the gas nozzle causing inadequate gas shield for weld seam |
| Remedy: | Remove welding spatter |
| Cause: | Holes in gas hose or hose is not connected properly |
| Remedy: | Replace gas hose |
| Cause: | O-ring on central connector has been cut or is faulty |
| Remedy: | Replace O-ring |
| Cause: | Moisture/condensation in the gas line |
| Remedy: | Dry gas line |
| Cause: | Gas flow is either too high or too low |
| Remedy: | Correct gas flow |
| Cause: | Insufficient gas flow at start or end of welding |
| Remedy: | Increase gas pre-flow and gas post-flow |
| Cause: | Rusty or poor quality wire electrode |
| Remedy: | Use high-quality wire electrode with no impurities |
| Cause: | For gas-cooled welding torches: gas is escaping through a non-insulated inner liner |
| Remedy: | Use only insulated inner liners with gas-cooled welding torches |
| Cause: | Too much parting agent applied |
| Remedy: | Remove excess parting agent/apply less parting agent |
Technical data
General
- for manually-operated welding torches: 113 V
- for mechanically-driven welding torches: 141 V
- Umax = 5 V
- Imax = 10 mA
The torch trigger may only be operated in accordance with the technical data.
The product conforms to the requirements of IEC 60974-7 / - 10 Class A.
General
- for manually-operated welding torches: 113 V
- for mechanically-driven welding torches: 141 V
- Umax = 5 V
- Imax = 10 mA
The torch trigger may only be operated in accordance with the technical data.
The product conforms to the requirements of IEC 60974-7 / - 10 Class A.
Gas-cooled welding torch - MHP 280i G PM
I (ampere) 10 min/40°C | 40% D.C.* / 280 A |
 | 0.8-1.6 |
 | 5.85 / 7.85 / 9.85 |
 | 0.55 A RMS |
 | 27 V AC |
 | 1-20 m/min |
* D.C. = Duty cycle
Water-cooled welding torch - MHP 320i W PM
I (ampere) 10 min/40°C | 100% D.C.* / 320 A |
| 0.8-1.6 |
| 5.85 / 7.85 / 9.85 |
 | 700 / 850 / 1000 |
 | 1 |
 | 3 |
 | 5.5 |
| 0.55 A RMS |
| 27 V AC |
| 1-20 m/min |
| * | D.C. = Duty cycle |
| ** | Lowest cooling power as per IEC 60974-2 |
Appendix
CircuitDiagram: MHP 280i G PM, MHP 320i W PM
CircuitDiagram: MHP 280i G PM, MHP 320i W PM