LOKERMANN GRAND TIG 250 DC PULSE, Руководство пользователя

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Further Controls Explained
LH Multifunction Display (9)
Before welding this displays the setting selected or being adjusted using the control knob (22). During welding it
displays welding current. The parameter setting displayed is indicated by the LEDs beside the display; Current
(A), Time (S), Percentage (%) and Frequency (Hz). If left inactive for several seconds, display will revert back to
main welding current setting.
TIG HF/ Lift Ignition Modes (15,16)
For TIG welding 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 electrical pulse 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 start systems. Lift arc starting 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 (20 )
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.
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)
Sets the main welding current . Unit(A) and setting range (5-250A).
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 (5-400A).
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 gas flow 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%).