Phoenix GP-NL Series
230V single-phase to 230V three-phase power for real shop loads
The GP-NL rotary phase converter line is the straightforward way to run 230V three-phase machinery where only 220V, 230V, or 240V single-phase utility service is available. Choose standard GP-NL capacity for a steady shop load, or an Auto-Zoned NL configuration when your operating load changes substantially.
What you are shopping
What makes the NL series different?
A Phoenix GP-NL system uses a rotary idler generator and control panel to create the third leg needed by 230V three-phase equipment. Unlike a static converter, a properly sized rotary converter can supply continuous three-phase power and support more than one machine. Unlike a VFD, it is a practical whole-shop source when several different loads may share the same converter.
This collection includes both standard GP-NL models and Auto-Zoned NL models. The standard line is the dependable choice for general machinery and shops with a predictable load. Auto-Zoned models provide two operating zones for facilities that alternate between much smaller and much larger loads.
Choose by operating profile
Find the right GP-NL range
Compact GP-NL systems
3–10 HPGP3NL, GP5NL, GP7NL, and GP10NL for smaller lathes, mills, saws, pumps, and single-machine workshops.
Mid-range GP-NL systems
15–30 HPGP15NL through GP30NL for larger machines or several pieces of equipment sharing one three-phase source.
Large GP-NL systems
40–100 HPGP40NL through GP100NL for production machinery, irrigation, elevators, and higher-capacity facilities.
Auto-Zoned NL systems
10/20–100/200 HPTwo-zone models for applications that alternate between lighter and heavier loads rather than holding one steady demand.
NLA AutoLink systems
Compressor dutyFor air compressors, HVAC, refrigeration, or high-inertia starts, compare the purpose-built NLA AutoLink collection.
Transformer-equipped systems
230V → 460VIf the equipment nameplate calls for 460V or 480V three-phase, shop an NLT, PLT, or NLTA system instead of a 230V-output NL.
Sizing
Size from the load that is hardest to start
Horsepower alone is only the starting point. Correct sizing also depends on motor type, starting method, nameplate amperage, whether machines start together, and the total load that will run at the same time.
Useful rule for standard motor loads
For many lathes, mills, pumps, and general shop motors, begin with a converter rated around twice the HP of the largest motor. Example: a 10 HP largest motor commonly points to a 20 HP converter.
2.5×Starting point for demanding loads
Compressors, HVAC, refrigeration, and high-inertia machinery can need additional starting capacity. Start around 2.5 times the largest motor HP or ask whether an NLA AutoLink is the better fit.
- Confirm motor nameplate data before ordering
- Keep total running load inside system capacity
- Have final wiring sized by a licensed electrician
Compare
NL, Auto-Zoned NL, or NLA?
| Series | Best fit | Operating pattern | Important note |
|---|---|---|---|
| Standard GP-NL | General 230V shop machinery | One predictable load range | Simple, durable whole-shop three-phase source |
| Auto-Zoned NL | Shops with a wide difference between light and heavy loads | Alternates between two power zones | Choose from paired ratings such as 10/20 or 30/60 HP |
| NLA AutoLink | Compressors, HVAC, refrigeration, high-inertia starts | Hard-starting motor applications | Ask Phoenix to verify compressor or HVAC sizing |
Applications
Equipment commonly powered by a GP-NL converter
Technical resource
NL Series master datasheet
Review model specifications, wiring information, and installation details before final selection.
FAQ
GP-NL rotary phase converter questions
Will an NL converter run equipment marked 220V or 240V three-phase?
Usually, yes. In North American usage, 220V, 230V, and 240V generally describe the same nominal voltage class. Always confirm the acceptable voltage range on the equipment nameplate. Equipment marked 460V or 480V needs a transformer-equipped solution or a different converter configuration.
Can one GP-NL converter run multiple machines?
Yes, when the converter is sized for the largest motor's starting demand and the total load that will run at the same time. Avoid starting the largest machines simultaneously unless that condition was included in the sizing calculation.
What is the difference between a standard NL and an Auto-Zoned NL?
A standard GP-NL is designed around one normal operating range. An Auto-Zoned NL provides two capacity zones, making it useful when a shop alternates between a much smaller load and a much larger load.
Should I use NL for an air compressor or HVAC unit?
Compressors and HVAC equipment can have demanding starts. A larger NL may work when properly sized, but Phoenix generally recommends evaluating an NLA AutoLink model for compressor, refrigeration, HVAC, and other high-inertia applications.
Can a GP-NL supply a CNC machine?
Many CNC machines can operate from a properly sized rotary phase converter. Because CNC equipment may include controls, servo drives, and internal transformers, provide the complete machine nameplate and electrical specifications for final sizing.
Does the converter change frequency?
No. An NL rotary converter creates three-phase power at the incoming utility frequency. In the United States that is normally 60 Hz. If the machine requires variable speed, frequency control, or 50 Hz operation, discuss the application before ordering.
Where should the converter be installed?
The standard NEMA 4 enclosure supports indoor or outdoor installation, but the final location must follow the manual, electrical code, required clearances, and local conditions. Have a licensed electrician install the system and required disconnects and protection.
How do I get an exact model recommendation?
Use the phase converter sizing wizard or call 800-417-6568. Have the input voltage, equipment voltage, motor HP, full-load amps, start method, and simultaneous-load list ready.