Lincoln Electric SQUARE WAVE TIG 355 Service Manual page 119

F-67
NORMAL OPEN CIRCUIT VOLTAGE WAVEFORM
HIGH VOLTAGE / HIGH FREQUENCY can damage test equipment.
• Perform all voltage and waveform checks with high frequency circuit OFF.
TROUBLESHOOTING AND REPAIR
DC TIG MODE
CAUTION
50V
This is the typical DC (+) output volt-
age waveform generated from a prop-
erly operating machine. Note that
each vertical division represents 50
volts and that each horizontal division
represents 2 milliseconds in time.
Note: Scope probes connected at
machine output terminals: (+) probe
to electrode terminal, (-) probe to
work terminal.
SCOPE SETTINGS
Volts/Div.....................50V/Div.
Horizontal Sweep .....2 ms/Div.
Coupling.............................DC
Trigger.........................Internal
SQUARE WAVE TIG 355
CH1
0 volts
2ms
F-67