Telwin Superior 400CE VRD-Migpack 400V Bedienungsanleitung Seite 6

must be connected respecting the following pinout:
- 24 VAC 50/60 Hz 10 VA between pins 1 and 2; solenoid valve
supply input.
- 32 VAC 50/60 Hz 190 VA between pins 1 and 3; motor supply input.
- The unification of the 0 VAC must be performed on pin 1.
- Generator activation on pin 4; generator control output.
When the torch push-button is pressed, pin 4 is taken to the same
potential as pin 1. In other words, with the motor active, it returns
from the 24 VAC wire roller between pins 4 and 2.
When suitably managed this signal warns the generator that it must
supply current.
- Negative potential input of the welding machine output voltage on
pin 5; this allows the reading of the output voltage on the display in
Fig. B (6).
- Potentiometer in Fig. B (3) on pins 6 (minimum), 7 (maximum) and
8 (cursor). The potentiometer used is the 10KΩ 0.2W linear type.
- wire roller recognition input: wire feeder presence on pin 10. This
pin has the same potential as pin 6. When the control cable is
connected to the generator, pins 10 and 6 are short-circuited.
When suitably managed
Recommendations
- Fully rotate the welding cable connectors in the quick couplings (if
present), to guarantee perfect electric contact; if this is not the case
the connectors will overheat with relative fast deterioration and loss
of efficiency.
- Use the shortest welding cables possible.
- Do not use metal structures that are not part of the workpiece, to
replace the welding current return cable; this can be dangerous for
safety and give unsatisfactory welding results.
LOADING THE REEL OF WIRE (FIG. E)
CAREFUL! BEFORE LOADING THE WIRE, MAKE SURE
THE WELDING MACHINE IS OFF AND DISCONNECTED FROM
THE MAINS.
MAKE SURE THE WIRE FEEDERS, THE WIRE GUIDE HOSE
AND THE TORCH CONTACT PIPE CORRESPOND WITH THE
DIAMETER AND NATURE OF THE WIRE TO BE USED AND
THAT THEY ARE CORRECTLY MOUNTED. DO NOT WEAR
PROTECTIVE GLOVES WHEN THREADING THE WIRE.
- Open the reel area door.
- Position the coil of wire on the reel; make sure the reel pulling pin
is correctly housed in its hole (1a).
- Free the pressure counter feeder/s and distance it/them from the
lower feeder/s (2a).
- Make sure the pulling feeder/s is/are suitable for the wire being
used (2b).
- Free the wire end, cut off the misshaped end by cutting it cleanly
and without leaving a burr; rotate the reel counter-clockwise and
position the wire end into the wire feed input, pushing it by 50-100
mm into the torch connecting wire feed (2c).
- Reposition the counter-roller/s, adjusting the pressure at an
intermediate value, make sure the wire is positioned correctly in
the hollow of the lower feeder (3).
- Gently stop the reel, using the relative adjustment screw in the
centre of the reel itself (1b).
- Remove the nozzle and contact tube (4a).
- Insert the welding machine plug into the mains socket, switch
on the welding machine, press the torch push-button or the wire
forward push-button on the control panel (if present) and wait for
the end of the wire. which is running along the whole wire feed
casing, to exit by 10-15 cm from the front of the torch, then release
the push-button.
CAREFUL! During these operations the wire is
being powered and is subject to mechanical force; if suitable
precautions are not taken there is a danger of electric shock and
wounds, and electric arcs striking:
- Do not place the torch mouth against parts of the body.
- Do not approach the torch gas bottle.
- Remount the contact tube and the nozzle onto the torch (4b).
- Make sure the wire exits regularly; set the roller pressure and reel
braking to the lowest values possible, making sure the wire does
not slide in the hollow and that when the drive stops the wire turns
do not become loose because of too much coil inertia.
- Cut the end of the wire that exits from the nozzle by 10-15 mm.
- Close the reel area door.
6. WELDING: PROCESS DESCRIPTION
PRELIMINARY OPERATIONS
- Open and adjust the protective gas flow using the pressure
regulator.
- Switch on the welding machine and set the welding voltage/current
from the generator, using the potentiometer seen in Fig. B (3).
WELDING
Once the machine has been set following the operations indicated
previously, place the earth clamp in contact with the workpiece to be
welded, keep the torch at a suitable distance from the workpiece and
press the torch push-button.
For difficult welding operations it is a good idea to practice on scraps,
using the adjustment knobs contemporaneously in order to improve
welding. If the arc melts into drops and tends to extinguish, increase
the wire speed or select a lower current value. If the wire points
violently on the piece and causes the material to project, reduce the
wire speed or select a higher welding current.
Remember that each wire gives best results with a specific forward
speed. If welding difficult pieces or for a long time, it is a good idea to
test different wire diameters to select the most suitable one.
Approximate values of current for the most commonly used wires are
given in Table (Tab. 3).
WELDING ALUMINIUM
ARGON or an ARGON-HELIUM mix of gas is used for this type of
welding. The wire to be used must have the same characteristics as
the base material. It is always preferable to use an alloy wire (e.g.
aluminium/silicon) and never a pure aluminium wire.
The only problem when MIG welding aluminium is that of managing
to pull well the wire along the whole torch, because aluminium has
scarce mechanical characteristics and the pulling problems increase
as the wire diameter decreases.
This problem can be avoided by making these modifications:
1 - Replace the torch casing with the Teflon model. To remove it, just
loosen the dowels at the torch ends.
2 - Use contact pipes for aluminium.
3 - Replace the wire feeders with the type for aluminium.
4 - Replace the steel casing of the input wire feed with the
corresponding one in Teflon.
SPOT WELDING (FIG. F)
With a spot welding system you can unite overlying sheets with
welding spots of filler metal.
The system is particularly suitable for this purpose because equipped
with an adjustable timer, which can be used to select the most
suitable spot welding time and, as a result, create spots with the
same characteristics.
To use the machine for spot welding, it must be prepared as follows:
- Replace the torch nozzle with the one for spot welding. This nozzle
is characterised by its cylindrical shape and because it has vents
for gas at its ends.
- Adjust the output voltage/current at a high value (voltage 28-40 V
corresponding to a current of 300-500 A).
- Suit the wire feed speed to the output voltage/current that was set.
- Adjust the spot welding time according to the thickness of the
sheets to be joined.
To spot weld place the torch nozzle flat against the first sheet, then
press the torch push-button to weld: the wire melts the first sheet,
passes through it and penetrates into the second one, creating a
melted wedge between the two.
Keep the push-button pressed until the timer stops welding.
With this procedure you can spot weld even in conditions where it is
not possible to weld using traditional spot welding machines, given
that you can join sheets that cannot be accessed from the rear, for
example boxed structures
In addition to that the operator's work is greatly reduced given the
extreme lightness of the torch.
The limits of use of this system are tied to the thickness of the first
sheet, while the second can be extremely thick.
RIVETING (FIG. G)
This is a procedure that can be used to repair dented or deformed
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