Omega TL-WELD User manual

CONTENTS
Page
3 Operating Instructions
4 Accessories
5 Front Panel Controls
6 Rear Panel Controls
6 Setting Up Procedure
7 Welding Instructions
8 Energy Settings
8 Electrodes
9 Maintenance
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TM

THERMOCOUPLE AND FINE WIRE WELDER
MODEL TL-WELD
Operating Instructions
The TL-WELD welder is designed for sensor manufacturers
to produce commercial grade thermocouple junctions, and by
users of large numbers of exposed junction thermocouples
such as test and development laboratories where multipoint
temperature sensing of test pieces is required.
No special skills are required and most people will be
capable of producing quality work with minimal practice. A
satisfactory thermocouple junction is produced without using
argon, but where argon is available a momentary purge is
automatically triggered immediately prior to the weld to give
optimum weld integrity.
Safety Note
1. Always protect the eyes with a suitable filter during
welding – never view the weld discharge with the naked
eye.
2. Avoid touching the rear of the welder during operation,
the power switch heat sink may run hot. This is a normal
operating condition.
3. Do not allow the hand to directly contact the welding
electrode during operation.
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Accessories
Standard: Wire Holding Pliers With Lead
Safety Glasses
Magnifying Eyeglass
Carbon Electrodes
Spare 2A Fuse
Argon Hose
Hexagon key (for electrode change)
Mains Lead
Footswitch (Allows One Handed
Operation)
Optional: Spare Carbon Electrodes
Gas Flow Meter & Valve
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Front Panel Controls
A. Arc Argon gas and weld current controlled by the “Weld”
switch. LED indication.
B. Purge Allows the gas line and electrode shield to be purged
of air prior to a new welding period.
C. Weld Switch: Initiates a welding operation (in “arc” mode also
opens the Argon valve).
D. Argon LED Indicates when the Argon control valve is open and
gas is flowing.
E. Wait LED Glows when weld charge is building.
F. Ready LED “Ready to Weld” indication.
G. Power Rotary control of the capacitor charge voltage.
H. Level selector Selects the total capacitance available giving
the following values with LED indication.
“LO” = 0 to 6 Joules
“MED” = 0 to 28 Joules
“HI” = 0 to 64 Joules
I. Electrode Holder Holds the replaceable carbon electrode
Which is accessible by removing the outer Argon
Shield. Also holds the red filter in place.
J. Red socket Output socket for using the pliers supplied or the
Optional resistance welding pen.
K. Black socket Output socket, this is only used with the resistance
welding plate in conjunction with the welding pen
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.
Rear Panel Controls
A. ON/OFF switch Power to instrument ON/OFF
B. Weld jack socket Footswitch connection
C. Argon inlet For connection to Argon supply.
Setting Up
1. Using a suitable connector fused at 5 amps, connect to mains
supply.
2. If Argon is to be utilised, couple argon hose to rear of welder.
Do not over-tighten as a good seal will be made with the nut
slightly more than finger tight.
3. Connect free end of argon hose to the argon supply via an argon
flow regulator.
4. Switch on.
5. Hold welding mode switch in “purge” position and adjust argon
flow to 8 litres per min.
The apparatus is now ready for use.
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Welding
Arc Welding
1. Connect the work-holding pliers to the red output
socket.
2. Depress the purge switch for 3 or 4 seconds to rid the
system of air.
3. Reset the mode to “Arc”.
4. Set the energy level to the desired value.
5. Prepare the wires to be welded and grip in the pliers,
leaving about 1mm or more protruding.
6. Position the wires 5 or 6mm in front of the carbon,
whilst steadying the hand.
7. Press the “weld” switch or foot switch and slowly
move the work towards the carbon until the arc is
struck.
8. Release the switch and remove the work for
examination.
Preparation of Wires for Arc welding
For small diameter wires, strip off about 12mm of
insulation and twist together. Then, with side cutters or
scissors cut the wire off square leaving sufficient
uninsulated material to give approximately 1mm
protruding when gripped in the welding pliers. Larger
diameter wires may be held side by side in the welding
pliers, but ensure that they are in firm contact with each
other and trimmed off square. This method will be found
useful for attaching solid leads to resistance thermometer
detectors. However, when attaching stranded leads, it
will be found more convenient to use the twisting method
and then to carefully untwist after welding.
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Energy Settings
Arc Welding
The following settings may be used as a guide. The correct
setting for a particular metal combination and wire gauge
will produce a spherical bead. A flattened bead indicates that
the energy setting is too high.
Wire Diameter (mm)
Switch at “LOW” 0.1 Switch at “HIGH” 0.3
0.15 0.5
0.2 0.7
0.25 0.8
Resistance Welding
Using scrap material, use the “Medium” range and try a
weld. Increase or decrease the setting incrementally until a
strong weld is achieved without undue thinning of the
ribbons. Should the pen tend to stick, trim the end of the
electrode by gently stroking it on the slipstone, making sure
that the end is kept flat and square to the axis of the pen.
Should the plate become discoloured, it may be cleaned
using fine wire wool or metal polish.
Electrodes
To replace or adjust carbon electrode, first turn the welder on
its side and slacken screw on base of argon shield, which
may be then pulled off. Revealing grub screw which holds
carbon electrode in place.
TUNGSTEN: The tungsten electrode is crimped into a screwed brass bush which
may be unscrewed from the pen assembly for replacement.
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Maintenance
Apart from keeping the electrode in good order, no other
maintenance is required.
Specifications
General
Energy Output 0-60 Joules
Welding Capacity Wires up to 1.1mm diameter
Duty Cycle Minimum 5-10 welds/min
Mechanical
Physical Dimensions 220mm Wide x 120mm High x
250mm Depth
Weight 4kg
Electrical
Power Supply 110-120 Vac or 220-250 Vac,
50-60Hz
Power Consumption Max 170VA dropping to 20VA
during charging
All information given is correct at time of going to press.
Please note that specifications and availability of certain
items may be subject to change.
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