True or False: Single phase motor startup causes greater flicker effects than three phase motors.

Single-phase motor startup indeed causes greater flicker effects compared to three-phase motors. The reason for this lies in the nature of how these motors operate.

Single-phase motors draw a significant amount of current upon startup. This high inrush current can lead to abrupt voltage drops within the electrical system, which results in flicker—visible fluctuations in light output in connected lighting systems. Because single-phase motors have only one supply phase, they lack the balanced and smoother operation seen in three-phase motors, which can better manage their startup currents.

In contrast, three-phase motors distribute the load across three phases, allowing for a more gradual increase in current as the motor starts. The balanced nature of three-phase power minimizes voltage fluctuations, resulting in less flicker during startup. Therefore, the assertion that single-phase motor startups cause greater flicker effects than their three-phase counterparts is accurate.