Firepower MST 140i, Operating Manual

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Firepower MST 140i
TROUBLE SHOOTING AND SERVICE 5-4 Manual 0-5338
5.03 Cleaning the Welding Power Source
WARNING
There are dangerous voltage and power levels present inside this product. Do not attempt to open or repair un-
less you are a qualified electrical tradesperson. Disconnect the Welding Power Source from the Electricity Supply
Voltage before disassembling.
5.04 Cleaning the Feed Rolls
Clean the grooves in the drive rolls frequently. This can be done by using a small wire brush. Also wipe off, or clean the
grooves on the upper feed roll. After cleaning, tighten the feed roll retaining knobs.
CAUTION
Do not use compressed air to clean the Welding Power Source. Compressed air can force metal particles to lodge
between live electrical parts and earthed metal parts within the Welding Power Source. This may result in arcing
between this parts and their eventual failure.
5.05 Volt-Ampere Curves
Voltage-Amperage Curves shows maximum voltage and amperage output capabilities of welding power source. Curves of
other settings fall between curves shown.
Welding Current (Amps)
0 10 20 30 40 50 60 70 80 90 100 110 120 130 140 150
Output V
oltage (V
olts)
0
30
50
40
60
20
10
MIG (GMAW/ FCAW)
STICK (SMAW)
TIG (GTAW)
Fabricator 141i
Art # A-11807
Figure 5-1: Firepower MST 140i Volt-Ampere Curves