As shown in the illustrated electrically operated watertight door controller, how is the rotation direction of the door motor reversed? Illustration EL-0115

Correct Answer: Option B — reversing the direct current direction through the motor armature and maintaining the same direct current direction through the motor series field

Reversing DC series motors requires reversing current direction exclusively through the armature while keeping series field polarity constant, effectively changing torque direction while preserving field flux alignment.