Chapter 5. Anomalies. Probable Causes. Possible Solutions - gala gar D-20 C Manual De Instrucciones

CHAPTER 5. ANOMALIES. PROBABLE CAUSES. POSSIBLE SOLUTIONS.

SYMPTOM. ANOMALY.
GENERAL PROBLEM.
NOTHING WORKS.
LIMITER TRIPS
ALTHOUGH THE MACHINE
IS CONNECTED AND WITH
LIGHT C ON, THERE IS NO
REACTION WHEN PRESSED
WHEN THE GUN IS
PRESSED, ALTHOUGH WIRE
COMES OUT, THE
CONTACTOR DOES NOT
WORK OR/AND THERE IS
NO SHIELDING GAS
WHEN THE SHIELDING GAS
IS RELEASED IT CONTINUES
FLOWING.
WHEN FINISHING
WELDING THE WIRE
REMAINS STUCK TO THE
TORCH CONTACT TUBE.
WHEN FINISHING
WELDING THE FINAL WIRE
LENGTH IS VERY GREAT.
THE EQUIPMENT DOES
NOT WELD CORRECT.
"IT ADJUSTS BADLY"
THERE ARE MANY
PROJECTIONS IN THE
WELDING PROCESS
D-20C / D-20C (V-I)
PROBABLE CAUSE.
The machine has no voltage in one or all its
vital elements.
Magnetothermal switch has low gauge for the
case. There may be a short circuit, which is
what causes the limiter to trip.
Problem in the power source-wire feed unit
connection.
Failure of the pistol switch which does not
make perfect contact.
Main electronic board of wire-feed unit faulty.
Voltage does not reach the Contactor or/and
solenoid valve.
There is impurity in the inside chamber of the
solenoid valve which prevents the piston from
closing completely.
The contactor has a very high opening delay.
The contactor has a very low opening delay.
The torch is withdrawn immediately when torch
pushbutton is no longer pressed.
Low effective welding voltage. Output wave not
correct.
The welding wire has a mechanical resistance
at the outlet, which prevents it from having a
regular speed.
Reactance chosen low.
Unsuitable shielding gas.
POSSIBLE SOLUTION.
1. Make sure there is voltage at the entry to the
machine, if not the tapping must be changed. It is
advisable to see if any magnetothermal has "blown".
2. Check that fuse D of the power source is not open.
3. The machine panels must be removed testing the
logical points of the electrical diagram.
Change the magnetothermal for another larger
gauge one. It is important for the magnetothermal
switch to have a characteristic slow type curve. It is
important for the magnetothermal switch to have a
characteristic slow type curve. In the event that the
electrical installation has limited power the welding
work must be tested at lower current levels.
Check that the electrical connection between the
power source and the wire-feed unit is correct. The
warning light of the wire-feed unit must be on. Check
the wire-feed fuse. Test the wire-feed electrical circuit.
Change the gun microswitch.
Replace the electronic card.
It must be established whether the fault comes from
the electronic board or if it is an electrical connection
fault.
Check that the contactor coils or/and solenoid valves
are not open.
Dismantle and clean the electrovalve.
Suitably adjust the potentiometer of final wire length
existing on the wire-feed unit.
Suitably adjust the potentiometer of final wire length
existing on the wire-feed unit.
The final wire length control system requires the
welding torch not to be immediately withdrawn when
the torch pushbutton is no longer pressed.
Check that there is not a phase failure in the supply
power.
Check that the electrical contact elements of the
welding circuit are correct: Welding mass, rusty or
very dirty surfaces, contact nozzle with greater
diameter than the wire, etc.
Test the electrical diagram of the power source: input
and output voltages to the rectifier.
Examine the welding gun. Blow the inside (cable)
with compressed air.
Change reactance tap H on the power source to a
higher value.
When welding normal steels we advise the use of a
gas mixture Ar-CO2.
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