Accessing Stored Faults

Plugging Power Circuit (Power Transistors OFF)

When the power transistors are OFF, flyback current from the collapsing motor field flows through the direction contact tips, armature, direction contact tips, current sensor, regen contactor and flyback diode D4D back to the motor field. This current continues the electrical braking action. As long as truck momentum is turning the armature opposite the pulsed direction, the motor continues to act as a generator. The generated current flows through the current sensor, regen contact tips, plugging diode D5D and back to the armature. When the truck has come to a stop, the armature no longer is turning opposite the pulsed direction. The motor stops generating current, D5D no longer conducts and the logics no longer detects that sensing wire #51 is a lower voltage than wire #1.

The logics will switch into drive mode, and normal acceleration in the opposite direction starts.