current required for DC tungsten argon arc welding or greater current is used. Arc holding current
( ie base current) influences cooling and crystallizing of the metal in the bath. The range is
determined by performance of the welding materials.When sheet is welding, smaller arc
holding current (base current) is usually used in order to reduce welding through and
deformation. When pulse width ratio (holding time of pulse current and base current) is
selected, both the heat input and features of pulse welding should be considered. Usually, it can
be selected between 30 -60%. Selection of pulse frequency(periodical change time of pulse
current) mainly depends on thickness of sheet and welding speed and operation custom of the
operator should be also considered.
9. SYSTEMATIC BLOCK DIAGRAM
10. TROUBLES AND PROBLEM SOLVING
+
-
Input
Rectifier
&Filter
Inverse
Circuit
25KHz
output
Rectifier
&Filter
AC220/230/240V
panel
H. F.
Control Circuit
Trouble
Causes
Problem Solving
Power lamp not light
1.No electricity input
2.Switch of welder fails.
1.Check incoming line
2.Replace the switch
Fan not rotating
1.Fan poer line is off.
2.Enclosure blocks the fan due to defor
mation
3.The fan fails.
1.Reconnect the line
2.Reform the enclosure
3.Replace the fan
Warning lamp lights
1.Over heat(yellow lamp lights)
2.Oer current(Green lamp lights)
1.Welding after cooling.
2.Input voltage too low or the machine fails.
No output of welder
1.Over crrent protection
2. Welder fails
1. Over load using
2. Maintenance in manufacturer or service center
Welding stops, and w
arning light is on
Self-protection has engaged
1.Display "801"
2.Display "802"
3.Display "804"
4.Display "805"
1.over-voltage, lower-voltage
2.over-temperature,
3.over-current,
4.torch switch always close
