Working Principle - gala gar SMART PRO 5.0 Manual Técnico De Instrucciones

Working Principle

Working Principle Working Principle Working Principle
The working principle of SMART PRO 5.0 (PFC)welder is shown as the following figure. Single phase
208V－460V±10%work frequency (50/60 Hz) AC is rectified into DC, three phase 208V－460V±10%work
frequency (50/60 Hz) AC is rectified into DC, then by PFC circuit, DC(about 750V)is converted to medium
frequency AC (about 20KHz) by inverter device (IGBT module), after reducing voltage by medium transformer
(the main transformer) and rectified by medium frequency rectifier (fast recovery diodes), and is outputted by
inductance filtering. The circuit adopts current feedback control technology to insure current output stably.
Meanwhile, the welding current parameter can be adjusted continuously and steplessly to meet with the
requirements of welding craft.
PFC
Single-phase AC DC
208-460V 50/60Hz
Rectify
Three-phase AC
208-460V 50/60Hz
Volt Volt- - - - Ampere Characteristic Ampere Characteristic
Volt Volt Ampere Characteristic Ampere Characteristic
SMART PRO 5.0 welders have excellent volt-ampere characteristic, seeing the following graph. In MMA
welding, the relation between the rated loading voltage U
When I ≤600A，U ＝20＋0.04 I
2 2
U
. . . .
SMART PRO 5.0
Medium
AC
Inverter frequency
transformer
Current positive-
feedback control
（V）；When I
2
2
（V）
Volt-ampere characteristic
64
Working
point
44
20
0
Medium
AC DC
frequency
rectify
and welding current I
2
2 2
＞600A，U ＝44（V）.
The relation of the rated loading
voltage&welding current
600
DC
Hall device
is as follows:
2
I
2 （A）
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