Phase Converter for a Waterjet Cutter

Phase Converter for a Waterjet Cutter

Waterjet cutters are among the most demanding pieces of equipment in any fabrication shop. The high-pressure pump is an extremely hard-starting load—it takes a tremendous amount of current to get that pump spinning from a dead stop. Getting the phase converter sizing right is critical to reliable, long-term operation.

How to Size a Phase Converter for a Waterjet

Because of the severe starting load, waterjet cutters require a larger converter relative to their HP than most other equipment:

For example, a 30 HP waterjet pump requires a GP100NL (rounding up from 90 HP). A 20 HP pump needs at least a GP60NL. Do not be tempted to undersize here—the startup surge is real and will damage an undersized converter.

Large Waterjets: Consider DualZone

Larger waterjet systems often benefit from a DualZone phase converter. DualZone units use two separate converter sections to deliver more robust three-phase power, better handle heavy starting loads, and distribute the electrical stress. If your waterjet is 30 HP or larger, ask us about DualZone options.

Check Your Electrical Service

Waterjet cutters draw substantial power. Before sizing a phase converter, confirm the amperage of your single-phase electrical service. A 50 HP waterjet pump at 230V will require a large service—your electrician can confirm whether your panel can support it. We are happy to advise on what service size you need.

Voltage Matters Too

Most shop waterjet cutters run on 230V three-phase. Larger industrial units may be 460V. Check the motor nameplate or manufacturer documentation. 460V systems require the NLT model with the step-up transformer.

Why Not Just Use a Utility Upgrade?

Three-phase utility service upgrades can cost $10,000–$50,000 depending on your location and the distance to the nearest three-phase line. A Phoenix phase converter delivers the same three-phase power for a fraction of the cost, installed in a day.

📞 800-417-6568 — Waterjet sizing requires getting it right. Our team has done this many times.