Pre-charge Resistor
( For WAP-7 / WAG-9 3 Phase Locomotive
DU120108003 replaceable with ABB*** Part No. 3EHN424095P1250
)
It is part of the Power circuit of the Traction Convertor.
During powering up of the convertor, charging
contactor is closed, so that the convertor DC link is
pre-charged through the charging resistor and the
diodes in the Valve Set.