Kemppi Kempact 251R Operating Manual page 23

1. Dynamics control
Dynamics function controls the rate of rise of current when the filler wire is in short circuit
with the welding plate. This control adjustment is necessary due to the alternative welding
parameters, materials, wire sizes, gas types and current values used.
The welding dynamics scale is –9 to +9. Negative values make the rise of current slower, which
results in a hotter and more fluid weld characteristic. Positive values make the rise of current
faster, which results in a colder welding condition. This can result in more spatter during
welding depending on the filler wire size and type used.
How to find the optimal dynamics setting?
Start by setting '0' and make a test weld after selecting the correct wire feed speed and
voltage values. Fine tune the welding arc by trying different values in the negative (-) and
positive (+) sides of the dynamics scale.
2. Control knob for wire feed speed or power (adaptive mode)
This control knob increases and reduces the speed of filler wire delivery or power to the
welding arc. The scale is regulated in meters per minute or amperes. There is also a graphical
display bar indicating the proportion of motor speed or power selected.
3. Control knob for voltage or arc length (adaptive mode)
This control knob increases and reduces the available output voltage of the machine to the
welding arc. The scale is regulated in volts and is also supported by a graphical display bar that
indicates the proportion of the available output voltage selected.
In adaptive mode this control knob offers minor arc voltage adjustment for fine tuning the
welding arc.
4. Timer button for spot welding and cycle arc welding
SPOT /
CYCLE
The spot and cycle arc timer offers two modes of function. By pressing and selecting the SPOT
timer, you regulate the time duration for one single 'SPOT' welding cycle from either 0.1 to 9.9
seconds of arc time. By selecting the 'CYCLE' arc timer you regulate the machine to a repeating
cycle of arc time and pause time. The pause time offered is 0.1 to 3 seconds. Select function by
depressing button 4. Regulation and adjustment of SPOT and CYCLE arc values are adjusted
by the voltage control (item 3). Function selection is confirmed by either one dot (SPOT TIME)
or dash line (CYCLE TIME) under the word 'Timer' in the display.
5. Selection of 2T/4T gun operating mode
2T / 4T
This button offers you two modes of welding gun functions. The selected mode is indicated as
either 2T or 4T in the display.
• In 2T mode the welding arc is started by a single press and hold of the welding gun
trigger. Welding continues whilst the trigger is held, and stops when the trigger is
released.
• In 4T mode the gun trigger is pressed and gas starts to flow. When the trigger is
released, the arc ignites. Welding continues unti the trigger is pulled and released for a
second time. This mode is useful for long welding durations.
© Kemppi Oy / 1135
EN
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