Tig Welding - Telwin TECHNOLOGY TIG 222 AC/DC Manual De Instrucciones

5c MAIN CURRENT (I )
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When in TIG mode, MMA represents the output current I
measured in Amperes.
5d ARC FORCE
When in the MMA mode, this is the dynamic "ARC-FORCE" overcurrent
(adjustment 0 ÷ 100%); the display shows the percentage increase as to
the value of the pre-selected welding current. This setting improves welding
fluidity and prevents the electrode from sticking to the metal piece.
6- Parameter setting (5) encoder knob and parameter selection key (5).
7- Alphanumeric display.
8- REMOTE CONTROL LED. Used to transfer control of the welding parameters to
the remote control.
9- ALARM signalling LED (the machine is blocked).
Resetting is automatic when the reason for alarm activation stops.
Alarm messages shown on the display (7) FIG. D1:
- "AL. 1" : the primary circuit protection thermal switch has been triggered (if
installed).
- "AL. 2" : the secondary circuit protection thermal switch has been triggered
- "AL. 3" : power line overvoltage protection has been triggered
- "AL. 4" : power line undervoltage protection has been triggered
- "AL. 8" : auxiliary voltage out of range
10- Green LED, power ON.
4.3 G.R.A. water cooling unit ENABLING and DISABLING instructions (where
applicable)
Enabling procedure:
1- Press the main switch (1) simultaneously with the right button on the front panel
(6a) to turn the machine on.
2- The code "G.r.a - OFF" will appear on the display after the machine is turned on
(factory settings: cooling unit disabled).
3- Turn the encoder knob (9) until the code "G.r.a - on" appears on the display.
4- Press the encoder button (9) once to confirm the selection.
The cooling unit is now enabled.
Disabling procedure:
Repeat the same sequence confirming the code "G.r.a. - OFF" to disable the unit.
NB: If the welding machine is set to "G.r.a. - on" mode, but no cooling unit has been
connected, the cooling circuit malfunction protection will be triggered after a couple of
seconds of operation (code "AL.9").
5. INSTALLATION
WARNING! CARRY OUT ALL INSTALLATION OPERATIONS AND
ELECTRICAL CONNECTIONS WITH THE WELDING MACHINE COMPLETELY
SWITCHED OFF AND DISCONNECTED FROM THE POWER SUPPLY OUTLET.
THE ELECTRICAL CONNECTIONS MUST BE MADE ONLY AND EXCLUSIVELY
BY AUTHORISED OR QUALIFIED PERSONNEL.
5.1 PREPARATION
Unpack the welding machine, assemble the separate parts contained in the package.
5.1.1 Assembling the return cable-clamp (FIG. E)
5.1.2 Assembling the welding cable-electrode holder clamp (FIG. E)
5.2 POSITION OF THE WELDING MACHINE
Choose the place to install the welding machine so that the cooling air inlets and
outlets are not obstructed (forced circulation by fan, if present); at the same time make
sure that conductive dusts, corrosive vapours, humidity etc. will not be sucked into
the machine.
Leave at least 250mm free space around the welding machine.
WARNING! Position the welding machine on a flat surface with
sufficient carrying capacity for its weight, to prevent it from tipping or moving
hazardously.
5.3 CONNECTION TO THE MAIN POWER SUPPLY
- Before making any electrical connection, make sure the rating data of the welding
machine correspond to the mains voltage and frequency available at the place of
installation.
- The welding machine should only be connected to a power supply system with the
neutral conductor connected to earth.
- To ensure protection against indirect contact use residual current devices of the
following types:
- Type A ( ) for single phase machines;
- Type B ( ) for 3-phase machines.
- In order to satisfy the requirements of the EN 61000-3-11 (Flicker) standard we
recommend connecting the welding machine to the interface points of the main
power supply that have an impedance of less than:
Zmax = 0.234 Ohm (3P+T 230V)
Zmax = 0.286 Ohm (3P+T 400V)
Zmax = 0.234 Ohm (1/N/PE 230V) 200A AC/DC
Zmax = 0.218 Ohm (1/N/PE 230V) 220A DC
- The IEC/EN 61000-3-12 Standard does not apply to the welding machine.
If the welding machine is connected to an electrical grid, the installer or user must
make sure that the machine can indeed be connected (if necessary, consult the
company that manages the electrical grid).
5.3.1 Plug and outlet
. The parameter is Connect a normalised plug (2P + P.E) (1~); (3P + P.E) (3~) - having sufficient capacity-
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to the power cable and prepare a mains outlet fitted with fuses or an automatic circuit-
breaker; the special earth terminal should be connected to the earth conductor (yellow-
green) of the power supply line. Table (TAB.1) shows the recommended delayed fuse
sizes in amps, chosen according to the max. nominal current supplied by the welding
machine, and the nominal voltage of the main power supply.
WARNING! Failure to observe the above rules will make the (Class 1)
safety system installed by the manufacturer ineffective with consequent serious
risks to persons (e.g. electric shock) and objects (e.g. fire).
5.4 CONNECTION OF THE WELDING CABLES
WARNING! BEFORE MAKING THE FOLLOWING CONNECTIONS MAKE
SURE THE WELDING MACHINE IS SWITCHED OFF AND DISCONNECTED FROM
THE POWER SUPPLY OUTLET.
Table (TAB. 1) gives the recommended values for the welding cables (in mm
depending on the maximum current supplied by the welding machine.
5.4.1 TIG welding
Connecting the torch
- Insert the torch current cable into the appropriate quick terminal (-)/~. Connect the
three-pin connector (torch button) to the appropriate socket. Connect the torch gas
pipe to the appropriate connector.
Connecting the welding current return cable
- This is connected to the piece to be welded or to the metal bench on which it rests,
as close as possible to the joint being made.
This cable is connected to the terminal with the (+) symbol (~ for TIG machines
designed for AC welding).
Connecting the gas bottle
- Screw the pressure reducing valve to the gas bottle valve, first inserting the special
reduction accessory supplied when argon gas is used.
- Connect the gas inflow hose to the pressure reducing valve and tighten the hose
clamp supplied.
- Loosen the ringnut for adjusting the pressure reducing valve before opening the
valve on the bottle.
- Open the valve on the bottle and adjust the quantity of gas (l/min) according to the
suggestions for use given in the table (TAB. 4); if it is necessary to adjust the gas
flow during welding this should always be done by adjusting the ring nut on the
pressure reduction valve. Make sure there are no leaks in the piping and connectors.
WARNING! Always close the gas bottle valve at the end of the job.
5.4.2 MMA WELDING
Almost all coated electrodes are connected to the positive pole (+) of the power
source; as an exception to the negative pole (-) for acid coated electrodes.
Connecting the electrode-holder clamp welding cable
On the end take a special terminal that is used to close the uncovered part of the
electrode.
This cable is connected to the terminal with the symbol (+)
Connecting the welding current return cable
This is connected to the piece being welded or to the metal bench supporting it, as
close as possible to the join being made.
This cable is connected to the terminal with the symbol (-)
Warnings:
- Turn the welding cable connectors right down into the quick connections (if present),
to ensure a perfect electrical contact; otherwise the connectors themselves will
overheat, resulting in their rapid deterioration and loss of efficiency.
- The welding cables should be as short as possible.
- Do not use metal structures which are not part of the workpiece to substitute the
return cable of the welding current: this could jeopardise safety and result in poor
welding.
6. WELDING: DESCRIPTION OF THE PROCEDURE
6.1 TIG WELDING
TIG welding is a welding procedure that exploits the heat produced by the electric arc
that is struck, and maintained, between a non-consumable electrode (tungsten) and
the piece to be welded. The tungsten electrode is supported by a torch suitable for
transmitting the welding current to it and protecting the electrode itself and the weld
pool from atmospheric oxidation, by the flow of an inert gas (usually argon: Ar 99.5)
which flows out of the ceramic nozzle (FIG. G).
To achieve a good weld it is absolutely necessary to use the exact electrode diameter
with the exact current, see the table (TAB. 3).
The table on the covering of the machine suggests the approximate current values to
use in the various material thicknesses with reference to DC welding of mild steel or
stainless steel.
The electrode usually protrudes from the ceramic nozzle by 2-3mm, but this may
reach 8mm for corner welding.
Welding is achieved by fusion of the edges of the joint. For properly prepared thin
pieces (up to about 1mm) weld material is not needed (FIG. H).
For thicker pieces it is necessary to use filler rods of the same composition as the base
material and with an appropriate diameter, preparing the edges correctly (FIG. I). To
achieve a good weld the pieces should be carefully cleaned and free of oxidation, oil,
grease, solvents etc.
6.1.1 HF and LIFT strike
HF strike:
The electric arc is struck without contact between the tungsten electrode and the piece
being welded, by means of a spark generated by a high frequency device. This strike
mode does not entail either tungsten inclusions in the weld pool or electrode wear and
gives an easy start in all welding positions.
Procedure:
Press the torch button, bringing the tip of the electrode close to the piece (2 -3mm),
wait for the arc strike transferred by the HF pulses and, when the arch has struck, form
the weld pool on the piece and proceed along the joint.
If there are difficulties in striking the arc even though the presence of gas is confirmed
and the HF discharges are visible, do not insist for long in subjecting the electrode to
HF action, but check the integrity of the surface and the shape of the tip, dressing it
on the grinding wheel if necessary. At the end of the cycle the current will fall at the
slope down setting.
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