Everlast Power i-MIG 353DPi, Руководство оператора

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BASIC MIG OPERATION
General Setup of Amps and Volts.
When you MIG weld with almost any basic MIG welder, there are
generally two main adjustments that most users are familiar with:
Voltage and Wire Feed Speed. (In this instance, the Power i - MIG
353DPi uses Amps instead of Wire Feed Speed and is discussed in
more detail below. There are other brands that do this as well, but
usually found in more advanced MIG welders) Both of these func-
tions serve a purpose while welding and adjusting each affects
distinct aspects of welder performance and finished weld quality.
The function of Voltage in MIG welding is to control the overall
width and to a great extent, the height of the weld bead. In other
words, voltage controls the bead profile. The Voltage adjustment
also controls arc length to a great extent when set in a proper ratio
to wire feed speed or Amps. Later, in the Pulse - MIG section you
will see that Voltage is set differently during Synergic Pulse MIG
than in basic MIG mode. However, for now, Volts remain fairly
constant while welding. A MIG welder is often referred to as a
“ Constant Voltage (CV) ” wire feeder.
If you are familiar with the Wire Feed Speed adjustment, then you
may not initially understand where the Wire Speed Adjustment is on
this machine. As a foundation to understanding MIG welding, you
should keep in mind that the Wire Feed Speed function directly
controls the Amp output of the machine, and the Amps, in turn,
control penetration. With the Power i - MIG 353DPi, the unit actually
displays in Amps, and not in Inches Per Minute. Intially, this may
be hard to understand, but it is a more accurate way of calibrating
your weld parameters. The fact that the Power i - MIG 353DPi is
displays amperage is not a disadvantage or an altogether different
function from wire speed. To use a “ non - technical ” expression,
Wire Speed and Amps are two sides of the same coin. You will be
controlling the same function as wire feed speed, but expressing it
in a different way. By using Amps as a reference for adjustment
you have a more accurate way of expressing and controlling weld
parameters. If you are used to using a wire feed setting to set up
your MIG welder, you probably have observed that the wire speed
that is needed to perform a weld is affected by wire diameter, all
other things being equal (Volts, metal thickness, type, etc.). A
smaller wire will require a faster wire speed to produce the same
Amps. A larger wire will require a lower wire speed to achieve the
Amps as a smaller wire at a higher speed. This is because the
diameter of wire controls or “ restricts ” the Amp delivering capability
of the wire (Ampacity). The faster the wire is fed, the more amps it
can deliver to the weld. By using Amps to directly represent this
function, you end up with a more accurate way of determining the
exact “ heat ” being put into the unit. Welding isn ’ t just about Amps
or just about Volts. Rather it is about total Wattage being put into
the weld (VXA=Watts) Wire speed is meaningless unless the wire
diameter is known. A procedure calling for a setting of XX.X Volts
and 280 inches per minute will not be accurate if you run out
of .035” wire during the middle of the project and have to finish
with .045” wire at the same settings. You ’ ll have entirely different
results. So, with this in mind, even in standard mode (non -
synergic mode), the user must input the diameter of the wire being
used so the projected Amp output on the welder can be accurately
computed. Keep in mind that this is a projected output. There are
a number of things that can affect the true Amp/Volt output of the
welder in standard MIG mode, however it will be still be quite close
to what is set. While actively welding, the display will change func-
tion and display actual amp and volt output. You may notice some
small fluctuations with both Volt and Amp output while welding.
This is normal and expected. In Synergic Pulse Modes this output
reading of the displays may seem to be off from what is set by a
more significant margin. This is normal. This is because while you
are actively welding, the unit is “ pulsing ” Volts and even Amps (in
double pulse) so Amps and Volts (Trim) will be computed as an
averaged value since there is no way to reflect the change in pulse
multiple times per second. If you are having difficulty understand-
ing the relationship between wire diameter, wire speed and amps it
can be easily figured with the following approximate industry con-
versions for non - pulse welding:
.023”: 3.5 x Amps = Inches per minute (IPM)
.025”: 3.1 x Amps = Inches per minute (IPM)
.030”: 2 x Amps = Inches per minute (IPM)
.035”: 1.6 x Amps = Inches per minute (IPM)
.045”: 1 x Amps = Inches per Minute (IPM)
To convert welding requirements that may mention wire speed
(IPM) into approximate Amps, or to find the Amp value equivalent
of wire speed that you may be used to, use the following conver-
sion formula:
.023”: IPM ÷ 3.5 = Amps
.025”: IPM ÷ 3.1 = Amps
.030”: IPM ÷ 2 = Amps
.035”: IPM ÷ 1.6 = Amps
.045”: IPM ÷ 1 = Amps
Keep in mind these are approximate conversions and do fall off in
accuracy as Amps are increased into the upper current limits for the
given wire diameter.
Even though you will find general recommendations about setting
the Amps, Volts and even shielding gas through a variety of free
downloadable apps and online calculators, every filler metal manu-
facturer has its own specific parameters for Volt and Amp settings
for each wire diameter and AWS alloy class of wire. Note that wire
speed isn ’ t usually mentioned in wire manufacturer specifications,
just volts and amps. The range of Volt and Amp parameters gener-
ally varies somewhat from brand to brand, so be sure to read the
packaging and/or manufacturer literature to determine what range of
settings are recommended. The wire diameter also limits the prac-
tical maximum thickness of what can be reasonably welded. The
issue with following charts, graphs and calculator recommendations
is that most people find them either too hot or too cold. For some
people, it may not even close. However, nothing can substitute for
watching the arc and listening to the sound of the arc. In the short
circuit transfer method of MIG welding, a crisp, steady sound, fre-
quently referred to as a “ Bacon frying sound ” should be heard. The
actual frying sound can vary somewhat and may have somewhat of
a high pitch whine to it somewhere between the sound of a flying
bee and a mosquito. If these sounds are present, look at the arc to
see if it is steady, and producing low amounts of spatter. If large
amounts of spatter are present, the puddle seems fluid (appears
wet) and the wire speed is within the targeted range, decrease volts
a little at a time to reduce the spatter. If this does not correct the
problem, change the torch angle and torch height. Hold the torch
more vertical, with less than a 15 degree deviation from vertical and
reduce stick - out of wire to 3/8” or less. If this still does not help,
reduce the wire speed. Some spatter is normal, though it should
be minimal overall.
Section 2 Setup Guide