47
TROUBLESHOOTING
The following operation requires sufficient professional knowledge on electric aspects and
comprehensive safety knowledge. Make sure the input cable of the machine is disconnected
from the electricity supply and wait for 5 minutes before removing the machine covers.
Before arc welding machines are dispatched from the factory, they have already been checked
thoroughly. The machine should not be tampered with or altered. Maintenance must be carried out
carefully. If any wire becomes loose or is misplaced, it maybe potentially dangerous to the user!
Only professional maintenance personnel should repair the machine!
Ensure the power is disconnected before working on the machine. Always wait 5 minutes after power
switch off before removing the panels.
Description of fault
Possible cause
The power LED is OFF and the fan is not
functioning
The primary supply voltage has not been switched ON
or input fuse has blown
The welding power source input switch is switched
OFF
Loose connections internally
The fault LED is ON and the fan is running
The machine is under over
-
heating protection status
and will recover automatically after the welding
machine has cooled down
Check incoming mains supply to ensure it is within
230V +/
-
15%
No high frequency is produced
Process selection switch is set to manual metal arc
(MMA)
Torch trigger switch lead is disconnected or switch/
lead is faulty
High frequency spark gap too wide or short circuited
Welding current reduces when welding
Poor work lead connection to the work piece
TIG electrode melts when arc is struck
TIG torch is connected to the (+) VE terminal
No gas flow when the TIG torch trigger
switch is depressed
Empty gas cylinder
Gas regulator is turned off
Gas hose is blocked or cut
Torch trigger switch lead is disconnected or switch/
lead is faulty
Difficult to ignite the arc
The arc ignition current is too low or the arc
ignition time is too short
The electrode holder becomes very hot
The rated current of the electrode holder is smaller
than its actual working current, replace it with a
higher rated current capacity
Excessive spatter in MMA welding
The output polarity connection is incorrect, exchange
the polarity
Other malfunction
Contact your supplier
Summary of Contents for JT-300P
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