Mma Welding; Mma Welding Manual - Fimer TT255 AC/DC Manuel D'emploi

3. MMA WELDING

To select this welding mode, use switch 10,
select MMA and press confirm.
Select mode
MMA
TIG
Electric arc welding with a covered MMA (Metal
Manual Arc) electrode or SMAW (Shielded Metal
Arc Welding) is a manual welding procedure that
takes advantage of the heat generated by the
electric arc, which strikes between a covered
earthed electrode and the workpiece. This
procedure allows for the creation of joints in any
position, in the workshop, outdoors, in confined
areas or places that are difficult to access.
With the TT 255 AC-DC and TT 305 AC-DC it is
possible to weld any type of electrode and
diameter. The spark of the arc occurs by placing the
electrode close to the workpiece.
The correct connection of the electrode clamp
holder and the earth cable can be seen in the
table below:
Front Socket
WELDING
PROCESS
14 di Fig.1
MMA EARTH CABLE
Always make sure that the earth and the electrode
clamp holder are kept far apart.
START
OPTIONS
Front Socket
+ -
12 di Fig.1
ELECTRODE
CLAMP HOLDER

3.1 MMA WELDING Manual

This mode can be accessed using switch 10.
Selecting this option will take you to the
welding screen:
Switch 9 in fig. 1 adjusts the welding current (very
thick workpieces require a higher current).
Furthermore, switch 10 adjusts the parameters
shown in the figure below:
ADJUSTMENTS AND SETTINGS:
Button 10 adjusts the welding settings on the
screen:
Arc Force: Used to set the increase in current as
a percentage of
the welding current, which the welder can provide
to keep the arc fully ignited.
Hot start: Used to set the current increase as a
percentage of the welding current, which the welder
can provide at the time the arc is struck.
Hot start span: Used to set the time during which
the hot start current is provided.
Polarity swap: Used to invert (ON) or otherwise
(OFF) the polarity of the output voltage/current.
Remote ctrl: Used to switch on (ON) or switch off
(OFF) the remote control of the intensity of the
current delivered.
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