Secondary Rectifier - Kemppi Minarc Evo 150 Service Manual

Service manual Minarc Evo 150 and 180
Minarc Evo 180 card:
1
IGBT 1
emitter
IGBT
IGBT 1 diode + upper separate
diode; forward bias condition
IGBT 2 diode + lower separate
diode; reverse bias condition
IGBT 1 diode + upper separate
diode; reverse bias condition
IGBT 2 diode + lower separate
diode; forward bias condition
If the transformer primary is disconnected, IGBT 1 emitter and IGBT 2 collector connection points can be
used separately to measure diodes one by one. In this case the table must checked twice: first using the
IGBT 1 emitter point only and then the IGBT 2 collector point.

4.3.1.3. Secondary rectifier

Mains supply voltage must
Use a digital multimeter to test the secondary diodes. Diodes are in groups, so it is not possible to
measure them one by one unless they removed from the board and measured separately.
Diode Positive test lead
Forward bias Negative output terminal
Reverse bias Positive output terminal
21
Kemppi Oy
DC-link
2
IGBT 2
collector
GND
Positive test lead
IGBT1 emitter/IGBT 2
collector
IGBT1 emitter/IGBT 2
collector
DC-link positive
GND
not
be connected during the secondary rectifier diode measuring.
Version 1.3
IGBT 1 emitter
Negative test lead
DC-link positive
GND
IGBT1 emitter/IGBT
2 collector
IGBT1 emitter/IGBT
2 collector
Negative test lead
Positive output terminal
Negative output terminal
30.9.2015
Result
0,2-0,7VDC
No value
No value
0,2-0,7VDC
Result
0,2-0,6VDC
No value