Machine Programme / What Is Plasma Cutting; Initial Instructions - Migatronic ZETA 60 Manuel D'instruction

MACHINE PROGRAMME
ZETA 60/100 is an air-cooled plasma cutting machine.
Welding hoses
The machine can be equipped with return current
cables, spare parts etc. from the MIGATRONIC
programme.
Trolley (option)
The machines can be delivered with a transport
trolley.
WHAT IS PLASMA CUTTING?
The plasma arc is a very hot arc obtained by
constricting a ionized gas into the small hole of the
torch tip. By limiting the arc width it is possible to
achieve very high temperatures (over 15.000 C°) and
very high velocity of the gas. The high temperature
melts the part to cut while the high speed of the gas
removes the molten metal from the workpiece.
The ideal gas to use for plasma is an inert gas, but
also compressed air can be used. However, the
presence of oxygen in the compressed air has to be
taken in consideration when designing the torch.
Plasma cutting torch
The plasma cutting torch is somehow similar to a TIG
torch but it is designed in such a way to force the arc
in a very small orifice in the torch tip.
The electrode is made with copper and at the end
there is a small part made with hafnium. The tip is
made with copper.
The compressed air goes through the torch and it is
used for creating the plasma gas and to cool the torch.
The arc ignition is obtained with a high frequency
discharge between the electrode and the tip (Pilot
Arc). The pilot arc is limited to max 3 seconds to
prevent heating of the torch and excessive wear on
the consumable parts.
When the torch is positioned close to the workpiece
the arc is transferred to the workpiece, the pilot arc
switches off and the cutting operation starts.
Cutting metal nets and grills
When the arc is transferred on the workpiece and the
cutting operation is started, it is necessary to move the
torch ahead constantly in order to have always the arc
between the torch and the solid metal. Otherwise, yhe
arc will switch off. The same would happen, if the
torch is moved away from the workpiece.
If it is necessary to cut a metal net or a grill or other
discontinuous materials the "Grid" option has to be
used by pushing the relevant key pad on the front
panel. In this mode the machine will always keep the
pilot arc on, thus preventing the arc from switching off.
In this cutting mode, however, the consumables and
parts of the torch will wear faster and the efficiency of
the cutting operation will decrease.

INITIAL INSTRUCTIONS

Connection to the net
Make sure the input voltage is correct. It should fit the
voltage specified at the type plate of the machine. The
machine is ready for use after the mains plug has
been mounted by autorised and qualified personnel.
The machine can be switched on and off at the mains
plug.
Connection of remote control
(ZETA 100 AUTOMAT)
ZETA 100 machines for automat use equipped with 8-
pole control interface can be controlled via a remote
control or a welding robot. The remote control socket
has terminals for the following functions:
A: Input signal for welding current, 0 –
+10V input impedance: 1Mohm
B: Signal ground
C: Arc detect – contact of relay (max.
1Amp), fully insulated
D: N.C.
E: Arc detect – contact of relay (max. 1Amp), fully
insulated
F: N.C.
G: Supply +24VDC. Short circuit protected with PTC
resistor (max. 50mA).
H: Supply ground
Generator use
This welding machine can be used at all mains
supplies providing sine-shaped current and voltage
and not exceeding the approved voltage tolerances
stated in the technical data. Motorised generators
observing the above can be used as mains supply.
Consult your supplier of generator prior to connecting
your welding machine. MIGATRONIC recommends
use of a generator with electronic regulator and
supply of minimum 1.5 x the maximum kVA
consumption of the welding machine. The guarantee
does not cover damage caused by incorrect or poor
mains supply.
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