For a three-phase six-pulse generator, the heat units are obtained by multiplying the base product kVp × mA × s by which waveform factor?

For a three-phase six-pulse generator, the heat units are obtained by multiplying the base product kVp × mA × s by which waveform factor?

• A. 1.0
• B. 1.35
• C. 0.75
• D. 2.0

Answer: (B)

Heat units quantify the heating effect in the X-ray tube and are found by multiplying the base product kVp × mA × s by a waveform factor that reflects how the generator delivers power. For a three-phase six-pulse generator, power is delivered with six pulses per cycle, which smooths the voltage and raises the average power during the exposure. This means more heat is produced than with a single-phase feed, so the base product is multiplied by 1.35 to give the heat units. Therefore, the correct factor is 1.35, yielding HU = kVp × mA × s × 1.35. The other factors correspond to different, non-standard waveform conditions (1.0 for single-phase, 0.75 or 2.0 for counters that don’t match how a 3-phase six-pulse system behaves). For example, if kVp × mA × s is 100, the heat units would be 135.

Heat units quantify the heating effect in the X-ray tube and are found by multiplying the base product kVp × mA × s by a waveform factor that reflects how the generator delivers power. For a three-phase six-pulse generator, power is delivered with six pulses per cycle, which smooths the voltage and raises the average power during the exposure. This means more heat is produced than with a single-phase feed, so the base product is multiplied by 1.35 to give the heat units. Therefore, the correct factor is 1.35, yielding HU = kVp × mA × s × 1.35. The other factors correspond to different, non-standard waveform conditions (1.0 for single-phase, 0.75 or 2.0 for counters that don’t match how a 3-phase six-pulse system behaves). For example, if kVp × mA × s is 100, the heat units would be 135.