The APC (arrow) regulates the 650 VDC power bus supply voltage to 28.5 volts DC to supply the low voltage machine control system and to charge the machine batteries.
The APC also regulates the 650 volt DC power bus supply voltage to 320 volts DC for accessory bus power. The accessory bus power supplies voltage to the HVAC system and the Electric Water Pump Control (EWPC) module to operate the electric water pump.
Additionally, the APC:
Monitors the DC system voltage to control the hazardous voltage present lamp
Detects ground faults (AC and DC) and reports the ground faults to the Implement ECM