Firepower MST 220i, Operating Manual

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FIREPOWER MST 220i
Manual 0-5343 3-13 INSTALLATION/SETUP
When MIG Mode is Selected
In this mode the control knob is used to adjust the output voltage of the unit. The welding voltage is increased
by turning the knob clockwise or decreased by turning the knob anti-clockwise. The optimum voltage level
required will dependent on the type of welding application. The setup chart on the inside of the wire feed
compartment door provides a brief summary of the required output settings for a basic range of MIG welding
applications.
When STICK Mode is Selected
In this mode the multifunction control knob is used to adjust arc force. Arc force control provides an adjust-
able amount of welding force (or “dig”) control. This feature can be particularly beneficial in providing the
operator the ability to compensate for variability in joint fit-up in certain situations with particular electrodes.
In general increasing the arc force control toward ‘10’ (maximum arc force) allows greater penetration control
to be achieved. Arc force is increased by turning the control knob clockwise or decreased by turning the knob
anti-clockwise
When LIFT TIG Mode is Selected
In this mode the multifunction control knob is used to adjust down slope. Down slope allows the user to
select the ramp down time at the completion of the weld. The main function of down slope is to allow the
welding current to be gradually reduced over a pre-set time frame such that the welding pool is given time
to cool sufficiently.
Note that when in 2T normal mode (refer item 12), the unit will enter down slope mode as soon as the trigger
switch is released (ie if the multifunction control knob is set to 5, the unit will ramp down from the present
welding current to zero over 5 seconds). If no down slope time is selected then the welding output will cease
immediately. If the unit is set to 4T latch mode, to enter down slope mode the trigger must be held in for the
selected time period (ie press and release trigger to commence welding, then press and hold trigger again to
enter down slope mode). Should the trigger be released during the down slope phase (4T only), the output
will cease immediately.
11. Arc Control (Inductance)
The arc control operates in MIG mode only and is used to adjust the intensity of the welding arc. Lower arc
control settings make the arc softer with less weld spatter. Higher arc control settings give a stronger driv-
ing arc which can increase weld penetration. Soft means maximum inductance while Hard means minimum
inductance.
12. Trigger Mode Control (MIG and LIFT TIG Mode only)
The trigger mode control is used to switch the functionality of the of the torch trigger between 2T (normal)
and 4T (latch mode)
2T (Normal Mode)
In this mode, the torch trigger must remain depressed for the welding output to be active. Press and hold the
torch trigger to activate the power source (weld). Release the torch trigger switch to cease welding.
4T (Latch Mode)
This mode of welding is mainly used for long welding runs to reduce operator fatigue. In this mode the opera-
tor can press and release the torch trigger and the output will remain active. To deactivate the power source,
the trigger switch must again be depressed and released, thus eliminating the need for the operator to hold
the torch trigger.
Note that when operating in LIFT TIG mode, the power source will remain activated until the selected downslope
time has elapsed (refer Item 10).