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4
3.3 DESCRIPTION OF PROTECTION
This device is protected by a normally closed thermostat
on the power transformer.
When the thermostat is tripped the machine stops weld-
ing, while the motor-driven fan continues to run and the
yellow LED lights.
After it has been tripped, wait a few minutes to allow the
transformer to cool down.
4 INSTALLATION
WARNING!
The MIG135 must be installed by qualified person-
nel. All connections must be made in full compli-
ance with all applicable rules and regulations.
Make sure that the wire diameter corresponds to the one
indicated on the roller, and mount the wire reel. Make sure
that the welding wire passes through the groove in the
small roller
30
.
Before connecting the power cable
13
, make sure that
the power voltage corresponds to that of the welder, then:
a) for permanent connection to the power mains
without a plug, you must insert a main switch having a
suitable capacity in compliance with the rated
specifications.
b) for a plug-socket connection, use a plug having a
suitable capacity in compliance with the rated
specifications. In this case the plug must be used to
completely disconnect the machine from the mains,
after setting the switch
22
to “O” (off).
The yellow-green wire must be connected to the ground
terminal. Connect the ground clamp
21
to the part to be
welded. The welding circuit must not be deliberately
placed in direct or indirect contact with the protection
wire except in the workpiece.
If the workpiece is deliberately grounded using the pro-
tection wire, the connection must be as direct as possi-
ble, using a wire at least as large as the welding current
return wire, and connected to the workpiece at the same
point as the return wire, using the return wire clamp or a
second grounding clamp placed next to it. All precautions
must be taken to avoid stray welding currents.
Turn the machine on using the switch
22
.
Remove the tapered gas tip by turning it clockwise.
Unscrew the contact tip.
Do not press the torch trigger until you have read the
instructions carefully.
It is important to make sure the machine is turned off
whenever changing the wire reel and wire roller, to pre-
vent the wire feed motor from starting accidentally.
Press the torch trigger and release it only when the weld-
ing wire comes out.
Welding wire can cause puncture wounds.
Never aim the torch at parts of the body, other people or
metals when loading the welding wire.
Screw the contact tip back on, making sure that the hole
diameter corresponds to the wire used.
Slide the tapered gas welding tip on, always turning
clockwise.
4.1 CONNECTING THE GAS HOSE
The gas cylinder must be equipped with a pressure reg-
ulator and gauge.
If the cylinder is placed on the cylinder holder of the
machine, it must be held in place by the chain provided
and be of an appropriate size to avoid jeopardizing the
stability of the machine.
Connect the gas hose leaving the back of the machine
to the pressure regulator only after the cylinder is in place.
Open the gas cylinder and set the gauge to approxi-
mately 20-25 CFH.
CAUTION: Make sure the gas used is compatible with the
material to be welded.
5 WELDING
5.1 WELDING MILD STEEL
5.1.1
With shielding gas.
Either 75% ARGON + 25% CO2 or 100% CO2 may be
used for welding mild steel.
Connect the cables according to the instructionsgiven in
the plate stuck inside the machine (see figure 2).
Select the welding current by means of the rotary switc
22
.
Move the torch near the welding point and press the trigger.
Adjust the potentiometerl knob
27
until the welding is
done with a constant, continuous noise.
If the speed is too fast, the wire tends to stick to the piece
and cause the torch to skip; if the speed is too low, the
wire melts in spaced drops or the arc does not remain lit.
When you have finished welding, turn off the machine and
close the gas cylinder.
For the correct welding angle see figure 3.
5.1.2
Without shielding gas.
Connect the cables according to the instructionsgiven in
the plate stuck inside the machine (see figure 2).
Use only diam. .035 flux cored wire that complies with
thestandard AWS AS.20 E71 TII or E71 TGS, suitable for
use without shielding gas.
Connect the ground cable clamp to the workpiece.
After connecting the cables, follow the instructions given
in paragraph 5.1.1.
NOTE: For compact, well-protected welds always work
from left to right and from top to bottom.
Remove all waste after each welding operation.
For the correct welding angle see figure 3.
Fig. 2