Whether you are replacing a motor on a lathe, conveyor, pump, or another piece of three-phase equipment, the first question is often whether you need 3 HP or 5 HP. These two 1800 RPM TEFC motors both run on 230/460V three-phase power and share the same basic design: totally enclosed fan-cooled, NEMA Design B, Class F insulation, and a maximum ambient temperature of 40°C. But they split on horsepower, frame size, service factor, frequency rating, and listed price.
The 3 HP Premium Efficiency Motor is listed at USD 363.99, while the 5 HP Severe Duty Motor is listed at USD 332.63, putting the higher-horsepower motor at the lower price with a USD 31.36 gap between the listings.
Quick verdict: Choose the 5 HP Severe Duty Motor when you need 5 HP and want the less expensive listed option. Choose the 3 HP Premium Efficiency Motor when advertised overload headroom on a 3 HP motor matters more to you than the price gap.
| Spec | 3 HP Premium Efficiency Motor | 5 HP Severe Duty Motor |
|---|---|---|
| Listed price | USD 363.99 | USD 332.63 |
| Price bar | ||
| Rated load | 3 HP | 5 HP |
| Frame | 182T | 184T |
| Voltage | 230/460V | 208-230/460V |
| Frequency rating | 60 Hz | 50/60 Hz |
| Service factor | 1.25 | 1.15 |
| Insulation class | Class F | Class F |
Where the 3 HP Motor Stands Out
- It lists the higher service factor of the pair and is listed as a direct replacement, so it suits applications where overload headroom is a priority.
- The premium-efficiency designation appears in the title itself.
Where the 5 HP Motor Stands Out
- It brings 5 HP in a severe-duty 184T design and also carries a 50/60 Hz frequency rating, while the 3 HP motor lists 60 Hz.
- As a listing, it is less expensive than the 3 HP motor even though it has more rated horsepower.
3 HP Premium Efficiency Motor (182T Frame)
The 3 HP model is built around a 182T frame and comes with a listed direct replacement fitment, which can simplify the shopping process if you are swapping out an existing motor. It is a TEFC, three-phase, 230/460V motor with the premium-efficiency label clearly in the title. The spec sheet lists a keyed shaft and a base-mounted design. Its limitation is that you are paying more money for a motor with less rated horsepower, so the value case is weaker unless the service factor matters to you.
5 HP Severe Duty Motor (184T Frame)
This motor is the more powerful of the two, carrying a 5 HP load rating in a severe-duty 184T frame. It is TEFC with a service factor that comes in below the 3 HP motor's listed figure, and it uses Class F insulation. The 50/60 Hz frequency rating gives it a spec advantage over a 60 Hz-only motor if your power supply is not always 60 Hz. At about 104 lbs, it is a substantial unit to account for in your installation space. The main trade-off is that its service factor is lower than the 3 HP motor's, so if maximum advertised overload headroom is the deciding factor, the 3 HP model takes that one.
Final Choice by Use Case
- For 5 HP applications: The 5 HP Severe Duty Motor wins on capacity and listed price.
- For 3 HP applications where overload headroom matters most: The 3 HP Premium Efficiency Motor wins with its higher service factor.
- For 50/60 Hz input flexibility: The 5 HP Severe Duty Motor is the pick.
