Firepower MST 180i Operating Manual page 38

Firepower MST 180i
9. Multifunction Control - Voltage, Down Slope & Arc Force
The multifunction control knob is used to adjust Voltage (MIG Mode), Down slope (LIFT TIG Mode) and Arc Force (STICK
Mode) depending on the welding mode selected.
The preview functionality provided on this power source is intended to act as a guide only. Some differences 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.
When MIG Mode is Selected
In this mode the control knob is used to adjust the MIG welding voltage of the Power Source. The welding voltage is
increased by turning the knob clockwise or decreased by turning the knob counterclockwise. The optimum voltage level
required will depend 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 adjustable 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 counterclockwise.
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 of the amperage 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 (Control No. 11), the Power Source will enter down slope mode as soon as the trigger
switch is released (ie if the multifunction control knob is set to 5, the Power Source will ramp down from the present
welding current to zero over 5 seconds). If no down slope time is set then the welding output will cease immediately. If
the Power Source 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.
10. 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 driving arc which can
increase weld penetration. Soft means maximum inductance while Hard means minimum inductance.
11. Trigger Mode Control (MIG and LIFT TIG Mode only)
The trigger mode control is used to switch the functionality of the of the MIG or TIG Trigger Switch between 2T (normal)
and 4T (latch mode)
2T (Normal Mode)
In this mode, the MIG or TIG Trigger Switch must remain depressed for the welding output to be active. Press and hold the
MIG or TIG Trigger Switch to activate the Power Source (weld). Release the MIG or TIG 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 operator can
press and release the MIG or TIG Trigger Switch 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 MIG or TIG
Trigger Switch
INSTALLATION, OPERATION AND SETUP
NOTE
3-10 Manual 0-5339