HTP Revolution 2500 Manual page 22

The Revolution 2500 allows you to adjust
TIG Hot start in both AC and DC. Most other
TIG welding machines, and all other high-
end, brand name welding machines, feature a
hot-start function that delivers a factory pre-
set amount of hot-start, for a predetermined
amount of time (typically in the range of
several dozen or several hundred
milliseconds). Some competitive machines
allow you to preselect a tungsten diameter,
which will, in some cases, change the hot-
start parameters of the machine. The
downside to this is that there is always hot-
start, and, although all TIG machines have a
minimum amperage listed in the literature,
they never actually start an arc at that
amperage since hot-start cannot be turned off.
Why is this so important? On very thin
material the ability to adjust hot start way
down, or even turn it off, can be a huge
advantage. Some find it helpful to light the
arc on a piece of filler rod resting on the work
piece so they don't burn through. Others use
run in tabs. With the ability to adjust the hot-
start parameters, those tricks become things of
the past.
If a low hot-start is such a great thing, then
why did we make it adjustable from Off or
from 5 to 100 amps?
Sometimes, depending on the size and type of
tungsten you use (the Revolution 2500 welds
best with 2% Ceriated tungsten), and,
depending on whether you are welding in AC
or DC and potentially collected a fair amount
of aluminum oxide on the tungsten, you may
find re-striking an arc hard after welding for
awhile. In this case, you might need a higher
starting amperage all together. But, first and
foremost, you need hot-start, and plenty of it,
to initially ignite the arc. With that being said,
most competitive machines with non-
adjustable hot-start generally have too much
hot start rather than not enough, which can
make welding thin materials challenging.
Your starting current does not always have to
be 4 amps! When working with thicker,
colder material (especially aluminum), a
higher starting current gives you better arc
ignition and arc stability.
DC MODE
To access the TIG - MAIN SETTINGS
submenu, press button
and the following screen appears :
The procedure to regulate the different
parameters ( Pre Gas , Slope Up , Slope Down
, Post Gas ) is the same of AC MODE.
In DC MODE is possible to access to the
pulse mode and the pulse mode settings .
The procedure to regulate the different
parameters of pulsing ( PPS , Peak Time,
BKGND ) is the same of AC MODE.
] ( Fig.4,ref.9 ),