Question 148Electricity/Electronics - QMED70% to pass
As shown in figure "B" of the illustration, when the DC motor in figure "A" is operating at minimum speed what are the armature and field characteristics? Illustration EL-0153
AI Explanation
The correct answer is B) The motor is operating at minimum armature voltage and maximum field current.
When a DC motor is operating at minimum speed, the armature voltage is at its lowest value while the field current is at its maximum. This is because to achieve the minimum speed, the motor controller reduces the armature voltage while increasing the field current. This configuration allows the motor to produce the necessary torque at the lowest possible speed.
The other options are incorrect because they do not accurately describe the motor's characteristics at minimum speed. For example, option A would result in maximum speed, while options C and D do not match the expected armature voltage and field current relationship at minimum speed.
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