What percentage voltage ripple is produced by x-ray equipment operated by three-phase 12-pulse power?

• A. 8% ripple
• B. 10% ripple
• C. 4% ripple
• D. 2% ripple

Answer: (C)

Three-phase 12-pulse x-ray equipment is designed to minimize the voltage ripple compared to single-phase systems. In a three-phase system, the alternating currents from three separate phase sources are combined in such a way that they provide a more stable voltage output, resulting in less fluctuation.

For 12-pulse systems, the voltage ripple is further reduced compared to the standard three-phase, 6-pulse systems. The ripple percentage for a 12-pulse system typically can be calculated, which results in about 4% ripple. This is significantly lower than what is produced in lower-pulse configurations, making 12-pulse systems preferable for high-quality imaging. This low ripple percentage indicates a more consistent and stable voltage supply for the x-ray tube operation, leading to better image quality and less patient exposure to radiation.

Thus, the choice of 4% ripple accurately reflects the performance characteristics of x-ray equipment using three-phase, 12-pulse power.