gala gar D-20 C Manuel Technique D'instructions page 15

SYMPTOM. ANOMALY.
THE WELDING START IS
VERY AGGRESSIVE.
THERE ARE MANY
PROJECTIONS.
SPECIALIZED PERSONNEL MUST CARRY OUT ANY WORK ON THE EQUIPMENT.
BOTH AT THE BEGINNING AND END OF A REPAIR CHECK THE EQUIPMENT INSULATION LEVELS.
DISCONNECT THE ELECTRONIC BOARDS WHEN MEASURING THE INSULATION.
The insulation-measuring device will have 500 V DC and will be applied to the following points of the
circuit:
- Intake rectifier-Earth: Ra> 50 Mohms
- Outlet rectifier-Earth: Ra> 50 Mohms
- Switch l2 - Outlet rectifier: Ra> 50 Mohms
- Control circuit-Earth: Ra> 50 Mohms
In the event that lack of insulation is observed it is likely that this is due to the accumulation of metal
dust on the inside of the equipment.
BOTH AT THE BEGINNING AND END OF A REPAIR, BLOW THE INSIDE OF THE EQUIPMENT WITH
RECOMMENDATIONS FOR REDUCING ELECTROMAGNETIC COMPATIBILITY (CEM) PROBLEMS
The user is responsible for the installation and use of the welding material according to the instructions in this manual and the following
recommendations.
Before installing the welding material, the presence of the following in the surrounding area must be kept in mind:
•
Wiring for power, control, signalling, and telephones.
•
Radio and television receivers and transmitters.
• Computers and other control equipment.
•
Critical security equipment.
• People with pace makers or hearing aids.
•
Measurement and calibration equipment.
In order to reduce EMC problems, keep in mind the time of day when welding or other activities will be carried out. Move possible
interference victims away from the welding installation.
ALWAYS CONNECT THE MACHINE TO POWER USING AN EFFICIENT EARTH TAP.
IF PROTECTIVE DEVICES OR SUPPLEMENTARY ELECTRICAL SYSTEM FILTERS ARE NEEDED, CONSULT OUR TECHNICAL
PERFORM THE MAINTENANCE OPERATIONS DESCRIBED IN THIS MANUAL.
USE THE SHORTEST WELDING WIRES POSSIBLE AND KEEP THEM PLACED NEXT TO EACH OTHER NEAR THE FLOOR.
IF THE WELDING PIECE IS GROUNDED, KEEP IN MIND OPERATOR SAFETY AND NATIONAL REGULATIONS.
D-20C / D-20C (V-I)
PROBABLE CAUSE.
Spotting jobs are being carried out with high
inductance intake.
Aluminium is being welded with a drawing
problem, which causes incorrect arc ignition as
the wire is slowed down on knocking against
the piece.
The motor acceleration ramp is very low,
reaching a high speed in the initial priming
process.
When starting the welding process the wire
length is very short, the wire "explodes".
The wire length at onset of welding process is
too long.
COMPRESSED AIR.
SERVICE.
POSSIBLE SOLUTION.
Place the earth tap at the lowest inductance value
Examine the drawing process. Prevent the gun from
making "knots", keeping it in a straight line. The wire
must not be slowed down when it knocks against the
piece
Suitably regulate the
potentiometer of the existing motor in the wire-feed
unit.
Suitably regulate the existing final wire length
potentiometer in the wire-feed unit to obtain the
GREATER final wire length at the end of the welding
process.
Suitably regulate the existing final wire length
potentiometer in the wire-feed unit to obtain the
LEAST final wire length at the end of the welding
process.
15
acceleration ramp