Cutting Operation; Cutting Speed - Migatronic ZETA Serie Manual De Instrucciones

Supply of compressed air
The compressed air hose has to be connected to the
back of the power source. The air should be clean and
dry in order to prevent fast wear of the torch parts. A
special air filter can be mounted in order to obtain this.
The compressor must have a capacity of at least
120 l/min by a pressure of 6-8 bar on ZETA 60 and
min. 180 l/min by a pressure of 6-8 bar on ZETA 100.
The compressor should not exceed 8 bar.
In the back of the power source there is an air filter
with a pressure gauge and a pressure regulator.
Adjustment of air pressure
The power source is equipped with a pressure switch
that will stop the machine if the input pressure goes
below 3 bar (see front panel above)
Switch ON the machine

Push the "air test" button on the front panel (the

gas valve will open)
Check the air pressure on the gauge and adjust it

to 3.5 bar while keeping the "air test" button
pushed. Different pressure values can be used
depending on the material type, thickness and the
Amperage. Do not exceed 6 bar.
Release the pushbutton

Please note!
It is important to control the flow by means of
the plasma gas test device.
The flow MUST be set between the two lines
on the gas test device.
If the flow is not within this area, it will result
in either bad cutting quality or decreased
lifetime on the wearing parts.

Cutting operation

Adjust the cutting current the value needed for the
material type and thickness.
Select cutting mode: normal or "grid".
Keep the torch away from persons or objects and
push the torch trigger. The pilot arc will start.
Position the torch close to the workpiece and the arc
will be transferred. If the torch is not moved close to
workpiece within 3 seconds after the pilot arc has
been established, the pilot arc will switch off and the
operation has to be repeated.
Start the cutting operation from one end of the work-
piece in order to prevent slag and spatters to return on
the torch. If the cutting operation has to be started in
the middle of the workpiece angle the torch in order to
avoid return of slag or spatters on the torch.
The pilot arc will allow the transfer of the arc also on
dirty or painted workpiece.

Cutting speed

The correct cutting speed allows to completely cut the
material and to remove the molten material from the
opposite side of the workpiece, avoiding return of
sparks and spatters.
With the right cutting speed the flow of molten material
will have an angle of 10-15° on the torch axle. This will
allow cut edges clean without slag.
Too slow cutting speed widens the cutting area,
increases the heat-affected zone and leaves slag on
the cutting surface.
Too high cutting speed will not cut the whole thickness
of the material and will give return of spatters and
sparks.
During the cutting operation the torch has to be kept
perpendicular to the workpiece.
Advantages of plasma cutting
Plasma cutting gives many advantages over
oxyacetylene cutting. The heat-affected zone is
smaller while the high content of oxygen in oxycutting
prevents the use on stainless steel. The temperature
of plasma cutting is higher than oxycutting and the
flow of compressed air removes the molten material
leaving clean cut edges.
Plasma cutting can be used on all electrically
conductive materials.
Wear parts
There are 2 parts in the torch subject to wear: the
electrode and the tip.
The hafnium end of the electrode wears during cutting
and when this wear has reached 2-3 mm the electrode
has to be replaced. A worn out electrode will make
difficult to establish the pilot arc, will give an unstable
arc and worse cutting quality.
The tip has to be kept clean from spatters. The orifice
will become wider and irregular and this will decrease
the cutting quality.
The lifetime of the consumables is variable and
depends also from the application.
Torch and spares
Use only original spare and wear parts.
Trolley with automatic mains voltage transition
(Special equipment)
Machines supplied with autotransformer can be
connected to the following mains supplies:
3*230V, 3*400V, 3*440V og 3*500V.
Press the power switch (1) to turn on the
autotransformer (green indicator light). The built-in
energy saver function will automatically turn off the
welding machine after 40 minutes of inactivity. Press
the button (2) to turn on the machine again (red
indicator light).
The energy saver function can be permanently
disconnected by a Migatronic technician.
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