A rotary phase converter turns single-phase into three-phase by spinning an idler generator off your utility supply. Two legs come straight from the utility, and the idler generates the third, giving you three-phase power for your machines. On a standard rotary converter, the voltage on that generated leg drifts as loads come on and off. Most motors tolerate that, but CNC controls and VFDs often do not, and can fault or shut down on unbalanced voltage.

The Smart-Phase adds a digital controller that uses VDT (Voltage Differential Technology) to compare voltage between each leg pair. When the readings drift apart, the 8-stage AVR system adds or removes run capacitance in steps, using solid-state switches timed to the AC waveform’s zero-crossing point. Each adjustment is small and clean, so the voltage balance stays within 2-3% whether a single machine is idling or several are running at full load.

When a downstream motor starts, such as a shop air compressor kicking on, the controller detects it and brings in starting capacitors for up to 300% boost current, then drops them out once the motor is up to speed. That stops the start from pulling voltage down on the rest of your equipment. Unlike a static phase converter, which starts a motor but cannot generate a true third leg, the Smart-Phase supplies full, balanced three-phase power the entire time your machines run.