Kemppi WELDFORCE KPS 3500, Service Manual, Page: 8 / 18

Main circuit components
Diode cards
Secondary choke and shunt resistor
Shunt amplifier
OCV smoothing circuit
X X
The main transformer T001 secondary voltages are full-wave rectified by the diode cards. The
secondary voltage waves are dampened by secondary choke L002. The secondary circuit current
is measured by a shunt resistor. The shunt´s voltage is amplified by shunt amplifier A001/2 and
taken to control card A001´s PWM-adjuster.
Control cable connection power supply
+ 50 VDC
Control card A001
power supply 2 x 20 VAC
No 220 V coil!
From auxiliary transformer T002 secondary voltages are formed the supply voltages for A001
and control cable connection´s auxiliary units.
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