58
AC TIG Operation
AC Wave Forms.
The wave form control is a
useful feature for achieving a desired type of
arc performance in AC mode. There are
2wave forms to choose from. These are the
most commonly useful forms, though there
are other types of wave forms. The standard,
default wave form is the advanced square
wave. This wave form is excellent for all
types of welding, and offers quick puddle wet
-
in, and good arc stability. The triangular
wave form is useful in situations where a
fast freezing puddle is desired, particularly
on thin aluminum. Total heat output is
affected regardless of an amperage. Using
the triangular wave form at the same amper-
age of the Advanced Square wave form will
demonstrate the difference. You should no-
tice a colder puddle with a different bead
profile. At the beginning, for all our users,
regardless of experience, we suggest that
you use the Advanced Square wave until you
are familiar with the machine.
AC Frequency.
The AC frequency only ap-
plies to the AC mode. Standard transformer
welders typically have a fixed frequency of
60 Hz which is essentially the line input fre-
quency supplied by the power company. But
with inverters, the capability of AC frequency
adjustment is practically limitless due to the
IGBT components that create its own fre-
quency. Frequency adjustment capability is
useful to help improve directional control of
the arc, and to focus the arc so that a nar-
rower bead profile can be achieved. Also, at
higher frequencies, the puddle agitation is
greater which improve the breakup of unde-
sirable oxides. All wave forms can be adjust-
ed from 20
-
200 Hz.
The AC output is formed by rapidly alter-
AC TIG operation is a new and unique feature
for compact MIG/TIG/Stick multi
-
process
units. With that said, this welder is a well
developed machine, with both HF start and
AC TIG/AC Pulse TIG features with industrial
capability in all processes. To be capable of
all processes, there are some equally unique
technological challenges to address. Ever-
last has sought to include everything possible
without compromising performance or quali-
ty without over complicating the machine.
While it is certain that others in the industry
will follow Everlast
’
s first to market model,
none will likely be as simple and convenient
to operate with less points of failure. In or-
der to eliminate the most points of failure
possible, we have chosen to include a sepa-
rate circuit for AC, which outputs directly
from the AC part of the inverter to a sepa-
rate AC terminal (DINSE connector) that is to
be used with the work clamp only when in
AC TIG or AC Pulse TIG modes. By doing this,
we have isolated possible interference from
the AC side of the machine with other cir-
cuits used for other processes. This has sim-
plified internal structure and reduced the
need to compromise performance. But you
will always need to make sure that the work
clamp is moved over to the AC terminal
when you change over to AC TIG. You will
not need to move the torch, as it will always
stay in the negative terminal. If you do not
manually relocate the work clamp to the AC
output terminal, you will experience erratic
operation, and in the long term, possibly in-
cur damage the internal components.
With the addition AC to the unit, there are a
few more items that should be covered in
greater detail to help the user to understand
exactly what is going on.
Basic Theory and Function
Section 3
