Three-Phase Voltage Stabilizer

three phase voltage stabilizer


To reduce diesel fuel consumption, a mobile transport generator was designed to plug into a three-phase power generator between service trips. A common problem emerged where the overnight three-phase A/C power plug could be wired incorrectly, causing the generators to run in reverse while plugged into high voltage A/C. The customer experienced high warranty claims for damaged parts. and sought out VeraTech Corporation in Minnesota to develop a voltage stabilizing solution.

Challenges Faced

High shock and vibration environments with large temperature variations while being exposed to diesel chemicals and repeated wash downs was home to this device. With a high voltage high current three phase A/C power source, safety was a major concern. Due to the need for a sealed, weather proof enclosure for protection, the three-phase voltage stabilizer could not generate any heat.


An optically isolated three phase voltage stabilizer was developed to universally identify proper phase control while operating over a voltage range of 170-600 VAC three-phase, while generating no heat. A microcontroller monitored wave shapes for continuity and voltage. An interlocked relay output controls each leg of the three-phase power source at the VAC input contactor, regardless of an improperly wired input.


Warranty claims were reduced to zero. The economic design has paid for itself in reduced claims. Today, over 300,000 three-phase voltage stabilizer units are in the field today.

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