11
General overview:
The Multi-Process PowerPro 256Si
offers an improved design with a new modular structure.
This new design includes digital control and a more ro-
bust internal design to improve reliability and perfor-
mance while simplifying circuitry and reducing weight.
The key features of the PowerPro 256Si include:
A. Digital control and componentized unit design reduc-
es complexity of circuitry and components, reducing
the overall number of components. This is aimed at
improving lifespan and long term serviceability of
the Multi-Process TIG/Stick Plasma platform.
B. Digital control offers more precise control over pa-
rameters, and offers a more satisfactory operating
experience by minimizing service and operational
issues found in the typical TIG/Stick/Plasma multi-
process welder/cutter unit.
C. Full-wave bridge rectifier inverter design also fea-
tures soft switching technology which further ex-
tends IGBT component life.
D. HF point gap adjustment issues have been reduced
with the introduction of new HF board design.
E. Digital components offer reduced weight and im-
proved operating efficiency over past analog con-
trolled generations.
F. The digitally controlled square wave design creates a
stable arc in AC, with a fast melting puddle and
good wet-in.
G. Adjustable arc force control and adaptive hot start
helps improve the SMAW process performance.
H. Plasma operation has been improved with a new
generation of torches featuring the iPT 60 torch.
General Use and Care
: With proper care, the PowerPro
’
s
digitally controlled inverter components are designed to
withstand years of use in many different welding envi-
ronments. However, remember to keep the unit out of
direct contact with water spray and corrosive areas. The
unit has an ingress rating of IP21S, for light dripping wa-
ter (condensation). It is a good idea to remove the weld-
er from the vicinity of any water or moisture source to
reduce the possibility of electrocution or shock. Never
operate in standing water or where water spray is an
issue. Every 1-2 months, depending upon use, the weld-
er should be unplugged, opened up and carefully cleaned
with compressed air. Regular maintenance will extend
the life of the unit. Metallic dust build up may lead to
premature board and component failure.
CAUTION: Before opening the unit for any reason,
make sure the unit has been unplugged for at least 10
minutes to allow time for the capacitors to fully dis-
charge. Severe shock and/or death can occur.
Free, unobstructed air flow is critical to cooling and duty
cycle. Do not restrict air flow or movement of air around
the welder. Allow a buffer distance of 2 ft from all sides,
with a minimum distance of
18”
clearance. Do not oper-
ate the welder in the immediate vicinity of the weld area
or the discharge of air from the fan will cause turbulence
and will destabilize the arc and cause weld porosity. Do
not mount in areas that are prone to severe shock or vi-
bration. Do not drop the unit. Lift and carry the welder by
the handle. Strap the welder down for maximum stability
during use. Do not direct metallic dust or any dirt toward
the machine, particularly in grinding and welding opera-
tions. Flip down the clear front cover after completing
adjustment to protect the control panel.
Duty Cycle.
For the PowerPro 256Si, the TIG duty cycle is
rated for 60% at 250 amps. The duty cycle is based off a
10 minute duty cycle rating at 40°C and 35% for Stick/
Plasma at 200/60 Amps, respectively. This means that the
unit is capable of being operated at the stated amps for 6
out of every 10 minutes without a break in welding to cool
down the unit. (3.5 out of 10 minutes for stick/plasma
operation.) For TIG a full 4 minute (6.5 minute for stick/
plasma) rest should be given if operating at or near maxi-
mum capacity of the welder for maximum life. The tem-
perature light will come on and the welder will automati-
cally stop welding when an overheat condition has oc-
curred. The fan and display will continue to be operate.
Do not turn the unit off or attempt to reset the unit for at
least 15 minutes after an overheat condition has occurred
as heat will continue to be generated by and transferred
to the electronics after welding has ceased. Welding in
humid or hot conditions greater than 40°C can negatively
affect duty cycle. Once the overheated condition has
cleared, welding can resume. Do not operate the welder
with the covers removed. The welder duty cycle interrupt
is controlled by temperature sensors and not time sen-
sors, so the duty cycle limiter function will differ some-
what from the actual time used based off the operating
conditions in the welding environment.
IMPORTANT!
Operating the PowerPro unit in such a way that causes
the unit to repeatedly surpass the duty cycle limit will
significantly decrease the life-span of the electronics or
cause permanent damage to the welder.
However, an
occasional duty cycle interrupt event should not be an
issue if the prescribed cool-down procedures are fol-
lowed. If you find that the unit is being repeatedly oper-
ated up to and beyond the duty cycle limit of the ma-
chine, it is likely that a larger welder/cutter is needed for
the job. Or, consider separate units with higher duty cy-
cles for dedicated service. Keep in mind many things can
Introduction and Specifications
Section 1
