Firepower MST 220i, Operating Manual

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FIREPOWER MST 220i
INSTALLATION/SETUP 3-14 Manual 0-5343
13. Process Selection Control
The process selection control is used to select the desired welding mode. Three modes are available, MIG
(GMAW/FCAW), LIFT TIG (GTAW) and STICK (SMAW) modes. Refer to section 3.19 or 3.20 for MIG (GMAW/
FCAW) set up details, section 3.22 for LIFT TIG (GTAW) set-up details or section 3.23 for STICK (SMAW)
set-up details.
Note that when the unit is powered OFF the mode selection control will automatically default to MIG mode.
This is necessary so as to prevent inadvertent arcing should an electrode holder be connected to the unit and
mistakenly be in contact with the work piece during power up.
14. Digital Voltage Meter (Right Digital Display)
MIG Mode
This digital meter is used to display the pre-set (preview) Voltage in MIG mode and actual welding voltage
of the power source when welding. At times of non-welding, the digital meter will display a pre-set (preview)
value of Voltage. This value can be adjusted by varying the Multifunction Control Knob (10).
STICK and LIFT TIG Modes
This digital meter is used to display the Welding Output Terminal Voltage in STICK / LIFT TIG modes during
non-welding or welding. This value cannot be adjusted by varying the Multifunction Control Knob (10).
When welding, this digital meter will display actual welding voltage in all modes.
At the completion of welding, the digital meter will hold the last recorded voltage value for a period of approxi-
mately 10 seconds in all modes. The voltage meter will hold the value until; (1) any of the front panel controls
are adjusted in which case the unit will revert to preview mode, (2) welding is recommenced, in which case
actual welding amperage will be displayed, or (3) a period of 10 seconds elapses following the completion of
welding in which case the unit will return to preview mode.
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.
15. Gas Inlet (MIG mode only for MIG Gun or Spool Gun operation)
The Gas Inlet connection,5/8-18 UNF female thread is used to supply the appropriate MIG welding gas to the
Power Source. Refer to section 3.18 or 3.19 for MIG (GMAW/FCAW) set up details
!
WARNING
Only Inert Shielding Gases specifically designed for welding applications should be used.
16. ON / OFF Switch
This Single Phase circuit breaker performs a dual function.
It is used to turn the unit ON/OFF and it will also trip in the event of a fault.
WARNING
When the front digital displays are lit, the machine is connected to the Electricity Supply and the internal
electrical components are at Mains voltage potential.