When you're picking an industrial motor, the first question isn't horsepower-it's what kind of power your facility supplies. Single-phase and three-phase motors serve different worlds, and choosing the wrong one means the motor simply won't run. This head-to-head puts the Single Phase 5HP SPL Air Compressor Electric Motor against the 3 Phase 56C Frame Motor to help you decide which one fits your setup.
Quick Verdict
If you have standard 230V single-phase power and need a motor for an air compressor, the Single Phase 5HP SPL Air Compressor Electric Motor is the straightforward choice. At $141.88, it's 19% less expensive than the three-phase motor, and it delivers 5HP with reversible rotation. If your shop runs on three-phase power and you want a totally enclosed fan-cooled motor that can handle dust and debris, the 3 Phase 56C Frame Motor at $175.10 is the better fit.
Comparison at a Glance
| Feature | Single Phase 5HP SPL Air Compressor Motor | 3 Phase 56C Frame Motor |
|---|---|---|
| Price | USD 141.88 | USD 175.10 |
| Phase | Single Phase | Three Phase |
| Voltage | 230V | 230/460V |
| Horsepower | 5HP | 2HP |
| Enclosure | ODP (Open Drip-Proof) | TEFC (Totally Enclosed Fan Cooled) |
| Rotation | CW/CCW (factory CCW) | Non-Reversible |
Beyond the Table
Beyond the obvious phase difference, the price gap is the next decision point. The single-phase motor costs $33.22 less, which matters if you're outfitting a small shop on a tight budget. But the three-phase motor's TEFC enclosure and inverter rating bring capabilities that a single-phase motor can't match, even at a higher price. The choice really comes down to your existing electrical service and the environment the motor will live in.
Where Each Motor Wins
The 3 Phase 56C Frame Motor wins for three-phase installations that need a fully enclosed, fan-cooled design. Its TEFC enclosure offers better protection against airborne particles, and the C-face design with removable base makes it flexible for mounting. It's also inverter rated and has Class F insulation, making it a solid option for more demanding three-phase applications.
The Single Phase 5HP SPL Air Compressor Motor wins for single-phase air compressor duty. It provides a full 5HP in a 56-frame with a 5/8" keyed shaft, and it can rotate in either direction, which helps if you're replacing an existing motor with unknown rotation. Plus, it costs $33.22 less than the three-phase motor.
Product Notes
Single Phase 5HP SPL Air Compressor Electric Motor
This motor is purpose-built for air compressor duty on a 230V single-phase circuit. The 5HP output with a 5/8" keyed shaft provides the torque needed to drive a compressor pump, and the 56-frame size fits many common compressor configurations. The dual rotation capability (CW/CCW) means you can adapt the motor to the pump's required rotation without ordering a different version, which is helpful for replacements. The open drip-proof enclosure allows heat to dissipate quickly, but it also leaves the windings more exposed to dust and moisture. For that reason, this motor belongs in a clean, dry location, not a damp or dusty shop corner. If you have an existing single-phase 230V supply and want a direct drop-in replacement, this motor's combination of horsepower, shaft size, and reversible rotation makes it a practical choice.
3 Phase 56C Frame Motor
This three-phase motor is designed for facilities that have 230/460V three-phase power available. The 56C frame includes a C-face mounting face and a removable base, giving you installation flexibility on brackets, bell housings, or other mounting systems. The TEFC (totally enclosed fan-cooled) enclosure seals the motor against dust, dirt, and light splashes, making it a strong candidate for sawdust-filled workshops or outdoor pump houses. With Class F insulation and inverter-rated construction, it can handle the demands of variable frequency drives without degrading. The key limitation is its non-reversible design: you must confirm the direction your machine requires before buying. Additionally, the 2HP rating means it suits lighter loads like pumps, fans, or conveyors rather than heavy air compressor duty.
Final Choice by Use Case
If your primary need is a single-phase air compressor motor and you want to spend less, the Single Phase 5HP SPL Air Compressor Electric Motor is the clear winner. If you're working with three-phase power and need a TEFC-protected motor for a machine tool or pump, the 3 Phase 56C Frame Motor is the right selection.
