Selco GENESIS 145, Repair Manual

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9.2) POWER BOARD 15.14.244
DESCRIPTION
This PC board contains the input rectfier bridge, the forward converter and the control logic. The main switch of forward power stage is
implemented with eight MOSFET connected in paralleling (MF1,MF,MF3,MF4,MF6,MF7,MF8 and MF9). The MOSFET MF5 is the active
clamp of the forward converter to get a quickly reset of the transformer and to better the performance of the power stage.
INSTRUMENTS REQUIRED
- Multimeter
- Set of pipe spanners for exagonal nuts
- Set of screwdrivers
BOARD
L1 L2 MF1 MF2 MF5 K1 R11/1 R11/2
MF3 MF6 MF8 MF9 MF7 MF4 PR1 PR-
L3 D30 R102 R103
NOTE:
JUMPER SOLDERED K1 IS NORMALLY CLOSED.
IF THE POWER PART IS DAMAGED AND THE POWER SUPPLIES PART NEEDS TO BE CHECKED, OPEN JUM-
PER SOLDERED K1 IN ORDER TO SEPARATE THE FAULTY POWER PART FROM THE SUPPLIES PART AND
TO AVOID DAMAGING OTHER PARTS.
WITH JUMPER SOLDERED K1 OPEN, SWITCH ON THE WELDING MACHINE AND CHECK THE SUPPLIES.
PR +
PR 2