Lincoln Electric PRECISION TIG SVM186-A Service Manual page 71

F-31
NORMAL OPEN CIRCUIT VOLTAGE WAVEFORM
HIGH VOLTAGE / HIGH FREQUENCY can damage test equipment.
• Perform all voltage and waveform checks with high frequency circuit OFF.
• Perform High Frequency Disable Procedure.
____________________________________________________________________
TROUBLESHOOTING AND REPAIR
AC STICK MODE
CAUTION
This is the typical AC output voltage
waveform generated from a properly
operating machine.
vertical division represents 50 volts
and that each horizontal division rep-
resents 2 milliseconds in time.
Note: Scope probes connected at
machine output terminals: (+) probe to
electrode, (–) probe to work.
SCOPE SETTINGS
Volts/Div.....................50V/Div.
Horizontal Sweep .....2 ms/Div.
Coupling.............................DC
Trigger.........................Internal
PRECISION TIG® 225
2ms
Note that each
F-31
50 volts
0 volts