14
Malfunction Phenomena
Solution
The protection LED is on.
1.
!
Overheating protection
1)
!
Check the welding current and working time. Operate
according to the data shown in the operator’s
manual.
2)
!
Check the fan’s running status when welding. If the
fan does not work, check if there is a power supply of
230V: If the power supply is normal, check the fan; if
the power supply is abnormal, check the connecting
cable of the power supply.
3)
!
Replace the thermal switch if it is damaged.
2.
!
Over current protection: This indicates a machine fault or
an accidental break-off caused by interference. Restart
the machine. If over current problem still exists, contact
the service centre..
No response when pushing the torch trigger and the
protection LED is off.
1.
!
Check if the power LED and the digital meter illuminate.
2.
!
Check if the torch trigger is in good contact, and check if
the welding torch is correctly connected.
3.
!
Check if the wire feeder is correctly connected.
When the torch trigger is pushed, wire feeder works and gas
comes out, but there is no output current, and the protection
LED is off.
1.
!
Check if the work cable is in good contact.
2.
!
Check if the wire feeder cable is connected correctly.
3.
!
Check if the welding torch is damaged.
There is output current when pushing the torch trigger to
feed gas, but the wire feeder does not feed wire.
1.
!
Check if the control cable of the wire feeder is broken.
2.
!
Check if the wire feeder is blocked.
3.
!
Check if the wire feed PCB of the welding machine fails.
4.
!
Check if the wire feeder is damaged.
Welding can be carried out when pushing the torch trigger,
but the current is too high, the voltage can not be adjusted,
and the no-load voltage is too high.
1.
!
Check if the control cable of the wire feeder is broken.
2.
!
Check if the control PCB of the welding machine fails.
3.
!
Check if the voltage/current feedback wire breaks.
Welding can be carried out when pushing the torch trigger,
but the current is too high, the voltage can not be adjusted,
and the no-load voltage is too high.
1.
!
Check if the control cable of the wire feeder is broken.
2.
!
Check if the control PCB of the welding machine fails.
3.
!
Check if the voltage/current feedback wire breaks.
Weld bead is not well protected.
1.
!
Do not move the welding torch away immediately when
stopping welding, so that the shield gas can protect the
weld bead.
2.
!
Prolong the post-flow time of the shield gas, and contact
our company.
The gas regulator cannot be heated.
1.
!
Check if the plug of the heater is well plugged in.
2.
!
Check if the resettable fuse inside the machine is in
good condition.
3.
!
Check if the heater inside the gas regulator is damaged.
There is no gas flow when the torch trigger is pushed, but
the wire feeder works normally.
1.
!
The control PCB is damaged.
2.
!
The solenoid valve is clogged or damaged.
Excessive spatter in MMA.
The output polarity connection is incorrect. Exchange the
polarity.
Summary of Contents for JM-250S MIG Series
Page 16: ...Electrical schematic 7 15 ...
Page 17: ...Parts list 8 16 ...
