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O R I G I N A L I N S T R U C T I O N S
slag-covered weld (IV). This will prevent metal spattering and pores being formed in the welded materials.
Care should be taken since the welded metal and the electrode are hot. It is after the weld has cooled down that the slag coating
should be removed by tapping it not too hard with a welding hammer. Welding can be started again where the previous process
was fi nished, after ensuring that the slag layer has been removed.
It is advisable to place the welder in a well-ventilated and shaded area away from any obstructions that may interfere with the
air fl ow through the welder’s ventilation system. Failure to ventilate will result in the welder components overheating, consequently
causing irreparable damage. During operation, do not leave the device in the sun or cover it with a blanket or other material that
may hinder air circulation.
Tips on how to use lift TIG lift welding with touch arc ignition (YT-81357, YT-81358)
Welded surfaces should be cleared of rust, grease, oil and paint. It is advisable to test the electrode and the set welding current
using waste material. Wear a welding shield. Place the ceramic nozzle of the TIG torch on the work surface so that only the ce-
ramic nozzle is in contact with the surface to be welded and the electrode is a short distance away. Open the shielding gas valve.
Then tilt the welding torch towards the work surface so that the electrode and the surface come into contact. Raise the torch so
as to form a gap of approx. 2 - 3 mm between the electrode tip and the workpiece. Arc initiation will occur. After the arc has been
initiated, set the tilt of the electrode. The electrode should be inclined at an angle of 70 to 80 degrees relative to the welding plane.
The electric arc melts the material, creating a liquid weld pool which solidi fi es when the arc is removed, forming a solid joint. When
thin materials, such as sheet metal, are welded, the materials can be joined without a fi ller metal (VI). When sheets up to 6 mm
thick are welded, it is advisable to feed the fi ller at an angle of 30 degrees to the welding plane (VII). To fi nish welding, lift the torch
to interrupt the electric arc. Close the gas valve.
Temperature/overload protection
Regardless of the operating manner, the welder may not be used with the maximum current in the continuous operation mode. The
rating plate presents the values of current and a 10-minute period percentage part when the welder can operate safely. During
the remainder of the 10-minute period the welder systems should cool down. Failure to observe the duty cycle will trigger the
overheating protection system. The indicator light marked with the thermometer symbol will then go on, meaning that the welder
systems need to cool down before welding can be resumed.
If overloaded frequently, the welder can wear faster or even become damaged.
YT-81355
Operation principles
The welder automatically sets various parameters to achieve good welding results:
HOT START - Some di ffi culties may occur when an electric arc is initiated to start the welding process. This is because both the
electrode and the welding area are cold. During start-up, for a very short period of time, the welder feeds a slightly higher current
to the electrode than was set. This allows easier arc initiation and makes the welding process more stable.
ARC FORCE (arc stabilisation) - During welding, the electrode is guided manually, which means that the distance between the end
of the electrode and the welding spot is not constant. To prevent the electrode from sticking during welding, the welder regulates
the current of the arc.
ANTI-STICK (anti-short-circuit function) - If the electrode sticks permanently during welding, the welder automatically reduces
the current to a value that allows the electrode to be detached from the weld, making it possible to continue the welding process.
VRD (Voltage Reduction Device) - This system is designed to switch o ff the power supply within a few milliseconds after welding.
It is also responsible for reducing the voltage at the covered electrode to a safe level.
O.C. (thermal protection) - If the thermal protection light marked as “O.C.” is activated on the control panel, it is not possible to
continue welding. The indicator light will automatically go o ff when the temperature drops to a level that allows further operation.
MMA welding
CAUTION! Before starting work, read the tips described in the section of the manual “Tips on how to use the MMA welding method”
Connect the welding cables to the correct terminals.
Connect the spring clamp to the metal part of the element to be welded. The contact area should be cleared of oil, paint or other
contaminants that may impair the fl ow of current.
Place the electrode in the torch. Regular or rutile electrodes can be used. Place the end of the electrode without a cover in the
clamp. The electrode must be fi xed in the clamp in such a way that it is not displaced in the clamp during operation. One jaw of
the torch has notches that fi x the electrode in place.
Electrode should be selected according to the type of materials to be welded.
Ensure that the earth clamp and the electrode are isolated from each other and do not come into contact, and that the
electrode or its clamp does not come into contact with the material to be welded.
Plug the power cord plug into the mains socket. Turn the switch on the back of the unit to the “on” position (I). The welder fan will
automatically switch on if the unit needs to be cooled down. The power light on the welder control panel will be on and the welding
current value will appear on the display. Use the regulator to set the welding current appropriate to the type and thickness of the ma-