Telwin MODULAR 20/TI Manuel D'instructions page 6

2. INTRODUCTION AND GENERAL DESCRIPTION
2.1 INTRODUCTION
Portable spot-welder for resistance welding.
The series consists of 3 models:
- Modular 20 TI:
Portable spot-welder with electronic timer. Used for precision spot-welding with
electronic control of spot-welding time, and electrode force adjustment. Spot welding
capacity on low carbon steel sheet (standard arms) up to 1+1 mm thick.
- Digital Modular 230:
Portable spot-welder with digital microprocessor control.
The most important properties managed by the control panel are:
- Selection of the thickness of the sheet to be spot-welded.
- Correction of spot-welding time.
- Possibility of enabling pulsed welding current.
- Adjustment of spot-welding force.
- Spot welding capacity on low carbon steel sheet (standard arms) up to 2+2 mm
thick.
- Digital Modular 400:
Portable spot-welder with digital microprocessor control.
The same features as the Digital Modular 230 model, but operating with a power
supply voltage of 400V(380V-415V).
2.2 STANDARD ACCESSORIES:
The standard spot-welder includes 120 mm arms and standard electrodes.
2.3 OPTIONAL ACCESSORIES
- Electrode arm pairs of different lengths and/or shapes, also in kits of several pairs.
- Trolley for arms: to carry the spot-welder and accessories.
3. TECHNICAL DATA
3.1 RATING PLATE (FIG. A)
The main data relating to use and performance of the spot-welder are summarised on
the rating plate and have the following meanings:
1- Number of phases and frequency of power supply.
2- Power supply voltage.
3- Rated mains power with 50% duty cycle.
4- Mains power with permanent running (100%).
5- Maximum loadless voltage over electrodes.
6- Maximum current when electrodes are shorted.
7- Maximum electrode force:
8- Current to secondary when running permanently (100%).
Note: The rating plate shown is an example to show the meaning of the symbols and
numbers; the exact values of the technical specifications for your spot-welder can be
found on the rating plate of the spot-welder itself.
3.2 OTHER TECHNICAL DATA
General specifications TAB. 1.
Weight of the spot-welder TAB. 7.
4. DESCRIPTION OF THE SPOT-WELDER
4.1 PRINCIPAL COMPONENTS AND ADJUSTMENTS (FIG.B)
1- Electrode force adjustment screw.
2- Left/right hand positionable handgrip.
3- Hole for eyebolt if used.
4- Movable welding arm.
5- Fixed welding arm.
6- Power supply cable.
7- Rating plate.
8- Microswitch.
9- Spot-welding time adjustment (only on 20TI models (FIG. B1)) ; for "DIGITAL"
models see 4.2: CONTROL PANEL.
10-Spot-welding lever.
4.2 CONTROL PANEL (only for "DIGITAL" models) (FIG. C)
1- Key for correcting spot-welding time.
- adjusts spot-welding time with respect to the factory default setting.
2- Key for selecting sheet thickness.
- selects the thickness of the sheet to be welded.
3- Key for selecting spot-welding mode.
9
: the welding current is pulsed.
Making this selection will improve spot-welding capacity on high yield
point sheets or on sheets with special protective film. The length of the
pulse is automatic and requires no regulation.
________ : Normal spot welding.
4- LED's for indicating triggering of thermal safeguard .
The two LED's flash alternately, the remaining LED's are off, indicating that the spot-
welder is shut down due to overheating; reset is automatic when the temperature
returns within the allowed limits.
5. INSTALLATION
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WARNING! CARRY OUT ALL INSTALLATION OPERATIONS AND
ELECTRICAL AND PNEUMATIC CONNECTIONS WITH THE SPOT-WELDER
COMPLETELY SWITCHED OFF AND DISCONNECTED FROM THE POWER
SUPPLY OUTLET.
THE ELECTRICAL AND PNEUMATIC CONNECTIONS MUST BE MADE ONLY AND
EXCLUSIVELY BY EXPERT OR SKILLED PERSONNEL.
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5.1 PRELIMINARY OPERATIONS
Unpack the spot-welder, assemble the separate parts included in the package.
5.2 LIFTING THE SPOT-WELDER
WARNING: None of the spot-welders described in this handbook have lifting devices;
when required attach an eyebolt to suspend the spot-welder using the hole made for this
purpose (FIG. F (2)), take care to insert the threaded bolt to a depth of no more than
8mm.
5.3 POSITION
The installation area must be sufficiently large and without obstacles, suitable for
ensuring completely safe access to the control panel, to the main switch and to the
working area.
When not in use position the spot-welder on a plane surface able to support the weight
(see the "technical data") so as to prevent it from tipping or moving dangerously.
5.4 CONNECTION TO THE MAIN POWER SUPPLY
5.4.1 Warnings
Before making any electrical connection, make sure the rating data of the spot-welder
correspond to the mains voltage and frequency available at the place of installation.
The spot-welder should be connected only and exclusively to a power supply with the
neutral conductor connected to earth.
5.4.2 Plug and socket
Connect a standard plug with adequate capacity to the power supply cable and prepare
a power outlet protected by fuses or by an automatic circuit-breaker; the appropriate
earth terminal should be connected to the (yellow-green) earth conductor of the power
line.
The power supply connection and the number of poles on the plug, which depend
on the distribution system and the power supply voltage of your spot-welder,
should correspond with the indications given in the tables (TAB. 2; 3; 4; 5).
The capacity of the plug and specifications of the fuses and circuit-breaker are given in
the tables TAB. 1 and TAB. 7.
Should more than one spot-welder be installed, distribute the power cyclically among
the three phases in order to obtain amore balanced load; e.g.
230V spot-welders:
Spot-welder 1: power supply L1-N.
Spot-welder 2: power supply L2-N.
Spot-welder 3: power supply L3-N.
etc.
400V spot-welders:
Spot-welder 1: power supply L1-L2.
Spot-welder 2: power supply L2-L3.
Spot-welder 3: power supply L3-L1.
etc.
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WARNING! Failure to observe the rules given above will invalidate the (class
I) safety system provided by the manufacturer, causing serious risks to people
(e.g. electric shock) and objects (e.g. fire).
_____________________________________________________________________________________________________________________
6. (SPOT) WELDING
6.1 PRELIMINARY OPERATIONS
Before carrying out any spot-welding operation, it is necessary to carry out a series of
checks and tests with the spot-welder disconnected from the main power supply.
1- Ensure that the electrical connections are correct, in accordance with the above
instructions.
2- Electrode force and alignment
- lock the lower electrode securely in the most suitable position for the job to be
done,
- loosen the fastening screw on the top electrode so that it is able to slide in the hole
in the arm,
- between the electrodes place a shim with the same thickness as the sheets to be
spot-welded,
- FIG. D close lever 2 until the arms are parallel and the electrode tips coincide;
insert screw 3 (d.M6) which is supplied into hole 1 and tighten it to lock the lever in
a suitable position for adjusting the electrode force,
- lock the top electrode in the correct position, tightening the screw securely,
- regulate the force exerted by the electrodes during spot-welding FIG.E, by
adjusting the screw (1) fitted for this purpose using the key supplied; the value of
the setting, according to the position of the indicator on the graduated scale, is
shown in FIG. F .
TAB. 6 shows the value of the force that can be obtained with different arm
lengths.
Turn it clockwise to increase the force in proportion to the increase in sheet
thickness but make the adjustment so that the clamp is able to close, and trigger
the corresponding microswitch, with very little effort.
6.2 ADJUSTING THE PARAMETERS
6.2.1 Digital Models
- select the thickness of the sheet to be spot-welded using the key (2 - FIG. C) on the
spot-welder control panel.
- select the type of spot-welding (continuous or pulsed) using the key (3 - FIG. C).
When necessary it is possible to correct the default spot-welding time upwards or
downwards using key (1- FIG: C).
6.2.2 Model TI
- regulate the spot-welding time using the potentiometer (9 - FIG.B1) on the back of the
spot-welder; using the lowest possible values compatible with correct execution of the
spot-weld (see 6.3 PROCEDURE).
6.3 PROCEDURE
To make a spot-weld, power the spot-welder then follow the instructions below:
- place the bottom electrode on the sheet to be spot-welded;
- pull the clamp lever to the end of its stroke, and hence until the microswitch is pressed
(8 - FIG.B) so that:
a) the sheets close between the electrodes with the preset force;
b) the welding current passes for the preset time.
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