NEIEP Mechanics Practice Exam

What are the largest wires on a DC traction elevator?

1. The wires to the main driving motor armature

2. The control circuit wires

3. Wires to the light system

4. Emergency wiring

The correct answer is: The wires to the main driving motor armature

The largest wires on a DC traction elevator are the wires to the main driving motor armature. This is because the motor requires a significant amount of current to operate, especially during start-up and under load conditions. The armature wires need to be able to handle this high current without overheating, which necessitates thicker conductors to ensure both efficiency and safety. In contrast, the other types of wiring, such as control circuit wires, wires for the light system, and emergency wiring, typically carry much lower currents and therefore can be constructed with smaller gauge wires. These wires are designed to perform specific functions and do not require the same level of current capacity as those supplying power to the main motor. Thus, the choice related to the armature wires reflects the necessity of accommodating the high electrical demands of the elevator's primary motor function.