Kemppi Mastertig MLS 3003 ACDC Service Manual page 30

Installation of semiconductors
Secondary rectifier Z002
Negative side diodes are
insulated from the heat sink by
mica insulators. Mica insulators
have to be replaced always,
when the secondary diode card
Z002 is separated from heat
sink !!!
Heat transferring paste is
applied as thin layers on both
sides of the mica insulators.
Absolutely no impurities are
allowed on surface of the
insulators when mounting them
between the heat sink and the
diodes!
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