USER MANUAL
JEFARC140M-230
140A
DC INVERTER ARC WELDER • 230V
~
50Hz • 13A
www.jeffersontools.com
7
INVERTER TECHNOLOGY
TERMINOLOGY
MMA -
Manual Metal Arc Welding
PWM
- Pulse Width Modulation
IGBT
- Insulation Gate Polar Transistor
CURRENT PROCESSES
This welding equipment is manufactured using advanced inverter technology. The single phase AC input voltage is rectified into DC current (about
300V) this is then inverted to medium frequency AC voltage (about 20KHz) by the inverter device (IGBT Module).
The voltage is reduced by a medium transformer and rectified before being outputted by inductance filtering. The circuit uses current feedback
control to ensure that the output current is kept at a stable rate.
This process is illustrated below in
Fig.1
:
This equipment is designed to deliver a constant current
output providing a more stable welding arc and a fast
dynamic response speed reduces the impact from the arc
length fluctuation to the current.
Note:
If the electrode touches the electrode during MMA
operation for longer than 1.5 seconds the welding current
will drop to the minimum current automatically to protect the
electrode.
This allows the use of a much smaller transformer, permitting
a significant weight saving and
improved power efficiency.
Volt-Ampere Characteristics
The relationship between the rated loading voltage
U²
and
welding current
I²
is shown in the equation and graph shown
in
Fig.2:
