AC standard general-purpose motors are versatile, widely used electric motors designed for common industrial, commercial, and residential applications. Unlike definite-purpose motors, which are optimized for specific tasks, general-purpose motors are built for broad usability across different loads and environments.
Enclosure Types:
• Open Drip-Proof (ODP) – Allows airflow but protects against falling liquids.
• Totally Enclosed Fan-Cooled (TEFC) – Sealed against dust and moisture.
Frame Sizes: Follow NEMA (T-frame, U-frame) or IEC standards. ( Like the IEC standards AC motors)
Mounting: Foot-mounted (FM), C-face, or D-flange options.
Voltage & Phase Options:
• Single-Phase (Common: 115V, 230V)
♦ Types: Split-phase, capacitor-start, PSC (Permanent Split Capacitor).
• Three-Phase (Common: 208V, 230V, 460V, 575V)
♦ More efficient, no start capacitor needed.
Speed: Typically 2-pole (3,600 RPM), 4-pole (1,800 RPM), 6-pole (1,200 RPM) at 60Hz.
Efficiency Standards:
• NEMA Premium® (Higher efficiency, lower energy costs).
• IE1, IE2, IE3 (IEC Standards) for international markets.
Duty Cycle: Continuous duty (S1) for long-running applications.
|
Application |
Motor Type |
Key Considerations |
|
Industrial Machinery |
3-Phase TEFC |
High torque, durable bearings |
|
Pumps & Compressors |
ODP or TEFC |
Corrosion resistance if wet |
|
Fans & Blowers |
PSC or 3-Phase |
Variable torque needs |
|
Conveyors |
3-Phase, high starting torque |
Constant torque, rugged design |
|
HVAC Systems |
TEFC, ECM (for efficiency) |
Thermal protection, quiet operation |
|
Feature |
General-Purpose Motor |
Definite-Purpose Motor |
|
Design |
Broad usability |
Optimized for specific tasks |
|
Efficiency |
Standard or Premium efficiency |
Often higher efficiency for the task |
|
Enclosure |
ODP, TEFC common |
May have special enclosures (washdown, explosion-proof) |
|
Control |
Fixed speed, basic VFD support |
May include ECM or specialized controls |
|
Applications |
Pumps, fans, conveyors, tools |
HVAC, refrigeration, agricultural |
Baldor (ABB)
WEG
Siemens
Marathon Electric (Regal Rexnord)
Toshiba
Nidec Motor Corporation
PJM (Power Jack Motion)
(1). Determine Power Needs (HP/kW, RPM).
(2). Choose Voltage & Phase (Single-phase for small loads, 3-phase for industrial).
(3). Select Enclosure (ODP for indoor, TEFC for harsh conditions).
(4). Check Efficiency (NEMA Premium® for energy savings).
(5). Mounting & Frame Size (NEMA 56, 143T, 182T, etc.).
Would you like recommendations for a specific application? Please let us know your motors request.
