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Installation of semiconductors
Z001 Main circuit card
Negative side IGBTs are insulated from
the heat sink by Mica/Aluminium oxide
insulators. Insulators have to be replaced
every time the main circuit card Z001 is
separated from the 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