Unlike most motors that start unloaded, compressors start against full tank pressure. The air in the tank doesn't go away when the motor shuts off. This means the compressor motor draws 5–8x its rated amperage on startup. A properly sized rotary phase converter delivers that surge power without breaking a sweat.

Compressors cycle on and off based on tank pressure — sometimes dozens of times per day. Our AutoLink models sense when the compressor needs power, start the converter automatically, and shut it down when the cycle is complete. Fully hands-free operation.

VFDs produce modified sine wave power full of harmonics. Compressor motors — especially hermetically sealed rotary screw compressors — generate excess heat from those harmonics. A rotary phase converter produces clean, true sinusoidal three-phase power identical to what the utility delivers. No harmonic damage. No voided warranties.

Our AutoLink converters include integrated overload and short-circuit protection — critical for compressor installations where unattended operation is the norm. If something goes wrong, the converter shuts down safely and protects your compressor motor from damage.

A single rotary phase converter can power your compressor AND other three-phase shop equipment — CNC machines, lathes, welders, dust collectors. Size the converter for the total simultaneous load and run everything from one panel.

Getting three-phase utility service installed typically costs $10,000–$50,000+ depending on distance and location. A rotary phase converter starts at a fraction of that, ships same-day, and can be installed in an afternoon by any licensed electrician.

• Most common in small to mid-size shops
• Brands: Ingersoll Rand, Quincy, Champion, Campbell Hausfeld
• Typical range: 3–25 HP
• Start under full tank pressure — size converter accordingly

• Continuous-duty industrial compressors
• Brands: Atlas Copco, Kaeser, Sullair, Ingersoll Rand
• Typical range: 10–100+ HP
• AutoLink recommended for unattended operation

• Clean, oil-free air applications
• Medical, dental, food processing, labs
• Typical range: 3–50 HP
• Sensitive to power quality — rotary converter is ideal

7.5 HP Ingersoll Rand reciprocating compressor powering paint booth spray guns, air tools, and sanders. Installed a GP10NL — runs the compressor plus a 3 HP exhaust fan simultaneously.

25 HP Atlas Copco rotary screw running 24/7 for CNC operations. GP30NL with AutoLink handles the startup surge and automatic cycling. Been running 3+ years with zero issues.

7.5 HP belt-driven compressor plus 7.5 HP planer. GP20NL runs both — sized up one step to handle the compressor's hard starts under load while the planer is running.

5 HP oil-free scroll compressor for dental air. GP5NL provides clean, balanced three-phase power with no harmonics — critical for sensitive medical-grade compressors.

1. Mount the converter panel — wall-mount near your electrical panel or compressor
2. Wire single-phase input — from your main panel to the converter (sized per NEC)
3. Wire three-phase output — from the converter to your compressor disconnect
4. Connect the idler motor — our pre-matched motor sits on the floor next to the panel
5. Power up and verify — check voltage balance and rotation direction

• NLT Series — 230V single-phase input → 460V three-phase output (manual start)
• NLTA Series — Same conversion with AutoLink for automatic operation
• PLT/PLTA Series — With magnetic starter for added safety on critical installations

We don't recommend it for most compressor applications. VFDs produce harmonic distortion that overheats hermetically sealed compressor motors and can void the compressor manufacturer's warranty. Rotary phase converters produce clean, utility-grade three-phase power that every compressor is designed to run on.

Yes — that's what rotary phase converters are built for. The idler motor stores rotational energy (like a flywheel) and delivers it during startup. Even compressors starting against full tank pressure get the 5–8x inrush current they need.

Absolutely. Size the converter for the total HP of everything that will run simultaneously. For example: 7.5 HP compressor + 5 HP lathe + 3 HP mill = 15.5 HP → use a GP20NL. Just don't start everything at the exact same moment.

If your compressor runs unattended (automatic on/off based on tank pressure), yes — AutoLink handles the cycling automatically and includes overload protection. If you're always in the shop and don't mind starting the converter manually, a standard NL or PL model works fine.

That depends on the converter model. Every unit ships with a complete wiring diagram specifying breaker size, wire gauge, and disconnect requirements. Our tech support team is also available at (800) 417-6568 to walk you or your electrician through the installation.

Most models ship same day if ordered before 2 PM MST. Transit time is typically 3–5 business days depending on your location. We ship freight (LTL) for larger models and ground for smaller units.