40 HP Rotary Phase Converter - GP40NL - Single Phase to Three Phase Converter

40 HP Rotary Phase Converter — Who It's For

The GP40NL is built for serious industrial operations. At 40 HP total running capacity with the ability to start motors up to 20 HP, this converter powers the kind of heavy equipment found in large machine shops, manufacturing plants, and commercial agricultural facilities that don't have access to utility 3-phase power.

Typical applications include:

• Large CNC operations running multiple VMCs, CNC lathes, and 5-axis machines with 15–20 HP spindles
• Heavy fabrication shops with large press brakes, plate rolls, structural ironworkers, and heavy-duty welding equipment
• Commercial woodworking plants powering large moulders, wide-belt sanders (15+ HP), industrial planers, and automated production lines
• Agricultural processing including large grain dryers, feed mills, irrigation pump stations, and cotton gins
• Quarry and aggregate operations running conveyors, crushers, and screening equipment
• Large commercial HVAC installations with 15–20 HP compressors

What the GP40NL Can Power

With 40 HP total running capacity and a 20 HP single-start capability, this converter handles substantial equipment loads:

• A 20 HP CNC machining center + a 15 HP air compressor + coolant systems and chip conveyors
• A 15 HP moulder + a 10 HP planer + a 10 HP dust collection system running simultaneously
• Multiple welding machines, a press brake, and an ironworker in a busy fabrication shop
• A 20 HP irrigation pump with VFD drive and monitoring equipment

Sizing Context

Choose the GP40NL when your largest single motor is 20 HP or less and total connected running load stays under 40 HP. For hard-starting applications like large scroll compressors or heavily loaded CNC spindles that start under full load, our DualZone models provide the extra starting torque these loads demand. If you're regularly starting motors over 20 HP, step up to a 50 HP or 60 HP converter.

Installation Overview — GP40NL

The GP40NL is an NL (No Link) model — the panel ships separately from the idler motor. You supply a suitable 40 HP, 1800 RPM, 3-phase motor and wire it to the panel. This saves significant shipping cost on the 539 lb idler motor if you can source one locally.

Key Installation Requirements

• Input Power: 230V single-phase
• Minimum Service Size: 50 KVA (200A) — many installations at this level benefit from a dedicated 200A service drop
• Breaker Size: 80A minimum, 200A maximum — double-pole breaker, properly torqued to manufacturer specs
• Single-Phase Supply Wire: 1/0 AWG copper (for runs under 50 feet). For longer runs, use 2/0 or 3/0 AWG per NEC voltage drop calculations
• Idler Motor Wire: 3 AWG copper between panel and idler motor
• Idler Motor: 40 HP, 1800 RPM, 3-phase motor (NEMA 324T frame). Weight: approximately 539 lbs (15" × 15" × 24")
• Foundation: The idler motor weighs over 500 lbs — mount it on a concrete pad or heavy-duty steel base. Rubber vibration isolators are recommended.

At this HP level, we strongly recommend having a licensed electrician perform the installation. The wire sizes and breaker ratings involved are substantial, and proper torque specifications on lugs and connections are critical for safe, reliable operation. Full details in our installation manual. If you'd prefer everything pre-wired and factory-tested, the GP40PL (Pre-Linked) ships as a complete, ready-to-install system.

Why Phoenix Phase Converters?

• Lifetime Warranty: A 40 HP phase converter is a major investment. Ours comes with a lifetime warranty because we build it to last.
• 90-Day Money-Back Guarantee: Risk-free purchase. If it doesn't perform, return it.
• American Manufacturing: Built in Phoenix, AZ with American-made components. No imported circuit boards or mystery parts.
• Heavy-Duty Construction: At 40 HP, undersized components fail spectacularly. Our contactors, capacitors, and bus bars are rated well above the minimum — because "just enough" isn't enough in a real shop.
• Expert Sizing Assistance: Call us before you buy. We'll review your equipment list and make sure you get the right converter — not one that's too small and not one that's bigger than you need.

Frequently Asked Questions — 40 HP Phase Converter

My shop has 200A service. Will that handle a 40 HP converter?

A 200A service meets the minimum requirement (50 KVA / 200A), but at 40 HP you'll be drawing a significant portion of that service. If your shop also has lighting, A/C, and other loads, you may need a service upgrade to 400A or a dedicated 200A meter for the converter. We recommend consulting with your utility company and electrician before purchasing.

Can I run a 25 HP motor on a 40 HP converter?

The GP40NL can start motors up to 20 HP. A 25 HP motor typically draws too much inrush current during starting for this converter. You could run a 25 HP motor if it's started with a soft-starter or VFD (which reduces inrush), but for direct across-the-line starting, you'd want a 50 HP converter.

What's the noise level?

The idler motor runs continuously when the converter is on. At 40 HP, expect noise levels similar to a large air compressor running — roughly 75–80 dB at 3 feet. Most shops install the idler motor in a utility room, on an outside pad, or behind a sound barrier. The motor is an open-frame design (ODP), so it needs ventilation but can be enclosed with proper airflow.