Migatronic PI 250 DC HP Manuel D'instruction page 14

Gas connection
Connect the gas hose, which branches off from the back panel
of the welding machine (2), to a gas supply with pressure
regulator (2-6 bar). (Note: Some types of pressure regulators
require an output pressure of more than 2 bar to function
optimally). Fit and secure the gas hose to the gas connection (6)
on the front of the machine.
Connection of welding cables
Connect the welding cables and the return current cable to the
front of the machine.
Please note that the plug must be turned 45 degrees after
insertion into the socket - otherwise the plug can be damaged
due to excessive contact resistance.
Always connect the TIG connection in the minus (-) socket (4)
and the return current cable in the plus (+) socket (5).
The control signals from the TIG torch are transformed to the
machine through the circular 7-pin plug (7). When the plug has
been assembled please secure it by turning the "circulator"
clockwise. Connect the gas hose to the quick connection.
COATED ELECTRODES: Electrodes are marked with a polarity
on the packing. Connect the electrode holder in accordance with
this marking to the plus or minus sockets of the machine.
Connection of a water cooling unit
Fasten the module under the machine with the fitting (10). Mount
the 4-poled plug (11) in the corresponding socket in the machine
(12). Mount the flow hose on the water cooled torch in the quick
connection marked with blue (13) and the return hose in the
quick connection marked with red (14).
If the machine is delivered with a separate water cooling unit, it
will be necessary to inspect the cooling liquid level by means of
the level control (8). The refilling of cooling liquid takes place
through the filler neck (9).
Connection of electrode holder for MMA
The electrode holder and return current cable are connected to
plus tap (5) and minus tap (4). Observe the instructions from the
electrode supplier when selecting polarity.
Connection of foot control
Foot control is connected to the 7-poled plug (7) or
through the 8-poled plug (15) (depending on the foot
control type).
Connection of remote control
PI machines equipped with 8-pole control interface (15)
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
Usage of the machine
When welding, a heating of various components of the
machine takes place and during breaks these
components will cool down again. It must be ensured
that the flow is not reduced or stopped.
When the machine is set for higher welding currents,
there will be a need for periods during which the
machine can cool down.
The length of these periods depends on the current
setting, and the machine should not be switched off in
the meantime. If the periods for cooling down during use
of the machine are not sufficiently long, the overheating
protection will automatically stop the welding process
and the yellow LED in the front panel will come on. The
yellow LED switches off when the machine has cooled
down sufficiently and is ready for welding.
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