If the circuit originates in a 120/240-volt, 3-phase, 4-wire panelboard, how many amps should the motor draw at startup?

To determine the startup current drawn by a motor connected to a 120/240-volt, 3-phase, 4-wire system, it is essential to consider the type of motor and its characteristics, particularly the type of starting method employed. Induction motors, which are commonly used in industrial applications, typically draw a significant inrush current during startup, which can be several times greater than their normal running current.

The startup current for a motor is calculated based on factors such as the full load current and the motor's service factor, as well as various characteristics like the motor's efficiency and power factor. Generally, the inrush current can range anywhere from 5 to 8 times the full load current. However, with a specific motor size and configuration, utilizing formulas and electrical codes can help derive a more precise figure.

Given the choices provided, if 397 amps is identified as the correct startup current, it implies that the specific conditions of the motor in question—like its horsepower rating and the inrush characteristics—have been taken into account to arrive at that value accurately. This indicates a higher power-demanding motor characteristic common in larger-scale applications, especially when initiating operation from a complete stop.

In summary, the reasoning behind the correct answer identifies