Oscilloscope Waveforms; Normal Open Circuit Voltage Waveform - Lincoln Electric POWER MIG SVM160-B Service Manual

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OSCILLOSCOPE WAVEFORMS MUST BE TAKEN IN MODE 201

NORMAL OPEN CIRCUIT VOLTAGE WAVEFORM

This is a typical DC output voltage waveform generated from a properly operating machine. Note that
each vertical division represents 20 volts and that each horizontal division represents 2.00 milliseconds in
time.
NOTE: Scope probes connected at the machine output terminals: (+) probe to electrode, (-) probe to work.
CODES 10562 AND BELOW
Power Mig 300 in mode 201. Mode 201 is a con-
stant current test mode.
1. Toggle and hold the Mode Select switch in the up
position.
2. Turn on the Power Mig 300.
3. Rotate the right output knob, while still holding the
Mode Select switch up, until the display reads
"ALL nodE".
4. Release the Mode Select switch and toggle the
Mode Set switch until the MSPlll panel reads 201.
Disengage the idler arm on the wire drive so no
wire will feed.
TROUBLESHOOTING & REPAIR
20.0 V
SCOPE SETTINGS
Volts/Div.....................20V/Div.
Horizontal Sweep ..2.5 ms/Div.
Coupling.............................DC
Trigger.........................Internal
POWER MIG 300
2.0 MS/DIV
CODES 10952 AND UP
Power Mig 300 in mode 201. Mode 201 is a con-
stant current test mode.
1. Toggle and hold the Mode Select switch in the up
position.
2. Turn on the Power Mig 300.
3. Once the display reads "Pres Spin" release the
mode select switch. Rotate the output knob until
the display reads "ALL nodE".
4. Toggle the Mode Select switch once and wait for
the machine to reset, then toggle the MODE SET
switch until the MSPlll panel reads 201. Disengage
the idler arm on the wire drive so no wire will feed.
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