Elevator Mechanic Practice Exam

How must a 9 lead 480/240 motor be wired for High Voltage?

1. L1(1-7) L2(2-8) L3(3-9) 4-5-6

2. L1(1), L2(2), L3(3), 4-5-6

3. L1(1), L2(2), L3(3), 7-8-9

4. L1(1-4) L2(2-5) L3(3-6) 7-8-9

The correct answer is: L1(1), L2(2), L3(3), 4-5-6

The wiring configuration of a 9 lead 480/240 motor for high voltage operation requires a correct grouping of leads to ensure proper functionality when connected to a power source. The correct answer should connect the first three leads (L1, L2, L3) to the designated terminals for each phase of the motor, while leaving the remaining leads unused for this particular setup. In option B, L1 is connected to lead 1, L2 to lead 2, and L3 to lead 3. Meanwhile, the leads 4, 5, and 6 are left unconnected, which is appropriate for a high voltage configuration. This arrangement allows the motor to operate effectively at 480 volts, as it uses only the necessary leads for this voltage level and ensures that the other leads do not interfere with the circuit. In contrast, other configurations may either connect too many leads or incorrectly group them, which could lead to improper motor operation or damage. Thus, the simplicity and correctness of option B make it the right choice for wiring a 9 lead motor for high voltage.