Firepower MST 220i, Operating Manual

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FIREPOWER MST 220i
Manual 0-5343 3-11 INSTALLATION/SETUP
4. Wirespeed/Amperage Control
In MIG mode, the Wirespeed/Amperage control knob adjusts the speed of the wire feed motor (which in turn
adjusts the output current by varying the amount of MIG wire delivered to the welding arc). The optimum wire
speed depends upon the material type and the welding application. The setup chart on the inside of the wire
feed compartment door provides a brief summary of the required settings for a basic range of MIG (GMAW/
FCAW) welding applications.
In STICK and LIFT TIG modes, the Wirespeed/Amperage control knob adjusts the amount of amperage (weld
current) delivered to the welding arc by the Power Source. It directly adjusts the Power Source to deliver the
desired level of weld current.
NOTE
The preview functionality provided on this power source is intended to act as a guide only. Some dif-
ferences may be observed between preview values and actual welding values due to factors including
the mode of welding, differences in consumables/gas mixtures, individual welding techniques and the
transfer mode of the welding arc (ie dip versus spray transfer). Where exact settings are required (in
the case of procedural work), it is recommended that alternate measurement methods be utilized to
ensure output values are accurate.
5. MIG Torch Adaptor (Euro Style)
The MIG torch adaptor is the connection point for the MIG welding torch. Connect the torch by pushing the
torch connector into the brass torch adaptor firmly and screwing the plastic torch nut clockwise to secure in
position. To remove the MIG Torch simply reverse these directions.
6. Positive Welding Output Terminal
The positive welding terminal is used to connect the welding output of the power source to the appropriate
welding accessory such as the MIG gun (via the MIG polarity lead), electrode holder lead or work lead. Posi-
tive welding current flows from the power source via this dinse type terminal. It is essential, however, that the
male plug is inserted and turned securely to achieve a sound electrical connection.
CAUTION
Loose welding terminal connections can cause overheating and result in the male plug being fused in
the dinse terminal.
7. MIG Polarity Lead
The polarity lead is used to connect the MIG gun to the appropriate positive or negative output terminal (al-
lowing polarity reversal for different welding applications). In general, the polarity lead should be connected
in to the positive welding terminal (+) when using steel, stainless steel or aluminum electrode wire. When
using gasless wire, the polarity lead is generally connected to the negative welding terminal (-). If in doubt,
consult the manufacturer of the electrode wire for the correct polarity. It is essential, however, that the male
plug is inserted and turned securely to achieve a sound electrical connection.
CAUTION
Loose welding terminal connections can cause overheating and result in the male plug being fused in
the dinse terminal.