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Installation of semiconductors
Z004 PFC card
IGBTs V4.. V7 are insulated from the heat
sink by Mica/Aluminium oxide insulators.
insulators must be replaced every time the
PFC- card Z004 is separated from heat
sink !!!
Heat transferring paste is applied as thin
layers on both sides of the insulators.
Absolutely no impurities are allowed on
surface of the insulators when mounting
them between the heat sink and the IGBT!
Note!
Aluminium oxide insulators are more
reliable in the primary and should be
used always if any primary repair work
is done. They are thicker than micas so
heat sink must be replaced.
Voltage of the heat sink is approx. + 400 V