Helvi GLOBUS 175HF Manual De Uso página 37

11.0 WELDER PREPARATION FOR HF START
- Connect the earth cable to the positive pole of the welder and the earth clamp to
the work piece.
- Connect the tig torch to the negative pole of the welder and the gas hose to the
pressure regulator of the gas cylinder.
The gas flow is automatically controlled using the post gas potentiometer
on the front panel.
Use inhert gas (argon) only.
- Set the down slope time considering the value of the weld current and the thickness
of the material (low current=low slope down time; high current = high down slope
time).
- Set the welding current considering the thickness of the material to be welded
and of the diameter of the tungsten electrode to be used.
- Switch the inverter on .
- Covering your face with a mask or a helmet, bring the tungsten electrode of the
torch within 3 or 4 mm of the work piece keeping it at an angle of 45° (fig. b) , push
the torch trigger (fig. a).The arc will be light from a high voltage spark(fig. c ).
FIG.b
12.0 2 / 4 TIMING
The TIG function included 2 timing and 4 timing, both controlled by the torch trigger
and selected by the proper switch on the front panel.
2 TIMING (2T)
By pressing the torch trigger the gas flow starts and the arc ignitiates. When the arc
is struck the output current reaches the value adjusted by the main current potentiometer
(8) on the front panel (Phase A) . By releasing the torch trigger the arc will break, the
welding current will decrease depending on the value set thru the Down Slope Time
Torch switch/Pulsante della torcia Torch Trigger
HF Spark
FIG.c
Workpiece
FIG.d