The GP50ASL AutoStart rotary phase converter delivers 50 HP of continuous three-phase power from your single-phase 230V service — and it starts and stops automatically. When your equipment calls for three-phase power, the GP50ASL fires up. When the load drops, it shuts down. No manual switch, no wasted electricity, no babysitting. Built for large workshops and industrial facilities that demand hands-free single phase to three phase conversion.
| Model | GP50ASL |
| Total Running HP | 50 HP |
| Largest Starting Motor | 25 HP |
| AutoStart | Yes — automatic on/off with load |
| Input Voltage | 230V Single-Phase |
| Output Voltage | 230V Three-Phase |
| Service Size | 50 kVA (200A) |
| Breaker Size | 80–200 |
| Single Phase Wire Size | 2/0 AWG (under 50 ft) |
| Idler Motor Wire Size | 2 AWG |
| Idler Motor | 601 lbs — 326T NEMA Frame |
| Electrical Panel | 80 lbs — 20" × 20" × 8" |
AutoStart Series Wiring Diagram — single-phase 230V in, three-phase 230V out with automatic start/stop
📦 What's Included
- ✅ 50 HP TEFC Idler Motor (continuous duty, cast iron frame)
- ✅ Pre-wired Electrical Control Panel with AutoStart
- ✅ AutoStart Load Sensing System (automatic on/off)
- ✅ AutoLink Soft-Start System (built in)
- ✅ Complete Installation Manual & Wiring Diagrams
- ✅ Lifetime Warranty — motor & panel
Why the GP50ASL AutoStart Phase Converter
The GP50ASL senses three-phase demand and starts automatically. When your equipment shuts off, the converter powers down — saving energy and reducing wear.
Clean, balanced three-phase power from your single-phase supply. Won't damage sensitive equipment or trip breakers under load.
One phase converter powers your entire shop — up to 50 HP of simultaneous three-phase load across all your equipment.
Thermal and magnetic protection safeguards your equipment. AutoLink soft-start system prevents inrush damage on startup.
Continuous duty rated. TEFC motor handles 24/7 operation in demanding environments — dust, heat, and vibration.
AutoStart eliminates idle run time. The converter only draws power when your three-phase equipment is actually running — cutting your electric bill.
IP65 Weatherproof Control Panel
Every panel is rated IP65 — fully sealed against dust and water jets. Install indoors or outdoors with confidence, even in harsh shop environments.
Heavy-Duty TEFC Idler Motor
Totally Enclosed Fan Cooled motor with cast iron frame, precision-balanced rotor, and sealed bearings. Built for decades of continuous industrial service.
🏗️ Common Applications for 50 HP AutoStart Phase Converters
The GP50ASL AutoStart phase converter is ideal for equipment that runs intermittently — it powers up automatically when you turn on your three-phase machine and shuts down when you're done.
GP50ASL Technical Documentation
Complete specs, wiring diagrams, and installation instructions for this AutoStart phase converter
Talk to an engineer — we'll size the right AutoStart phase converter for your exact setup
The GP50ASL is a 50 HP AutoStart rotary phase converter designed and manufactured by Phoenix Phase Converters in Phoenix, Arizona. This single phase to three phase converter provides reliable three-phase 230V power from a standard single-phase 230V service, with the added convenience of automatic start and stop. When your three-phase equipment turns on, the GP50ASL detects the load and starts the idler motor automatically. When the load is removed, it shuts down — eliminating wasted energy and manual switching.
The AutoStart feature makes the GP50ASL ideal for shops where equipment runs intermittently — CNC machines, compressors, pumps, and other three-phase tools that cycle on and off throughout the day. No need to walk to the panel to flip a switch before every use. The GP50ASL handles it automatically, so you can focus on your work.
Not sure whether you need an AutoStart or standard phase converter? Our engineers can help you choose the right configuration based on your equipment, workflow, and facility. Call us at (800) 417-6568 for free sizing assistance.
📡 Remote Monitoring Available
Track your phase converter from anywhere — voltage, temperature, run status, and automatic fault alerts. No WiFi hassle for you.
Learn About Remote Monitoring →🔁 Why AutoStart
GPX50L starts automatically when your equipment calls for three-phase power and shuts down when the load goes idle. No pushbutton, no manual sequencing, no wasted idler runtime — the converter senses load and cycles on demand.
Best for unattended pumps, HVAC compressors, refrigeration units, elevators, and any equipment where the operator can't (or shouldn't) touch a start button before every cycle. Cuts electricity cost and idler wear compared to a converter that runs continuously.
🛡️ Warranty & Support
Lifetime warranty on idler motor and control panel. AutoStart sensing circuit carries a 3-year replacement warranty. If any component is defective within the warranty period, Phoenix Phase Converters will repair or replace it at our discretion.
Return policy: Sealed, unopened packages are eligible for return within 90 days of purchase. Contact us before returning.
Dedicated engineering support: Every order is assigned to a Phoenix representative. Call (800) 417-6568 for sizing help, load-sensing calibration, or troubleshooting.
Helpful guides
Considering AutoStart for your application? Our knowledge hub covers the trade-offs:
- How AutoStart works and when to use it — load-sensing, cycle life, and best-fit applications
- How to size a rotary phase converter — sizing for intermittent-duty loads
- Digital vs AutoStart — which control is right for you? — regulation vs automation
- Phase converter FAQ — quick answers to the most common questions
