Industrial Engineer · phase 9 of 16
Output Current Rating
Maximum continuous motor current the drive can supply under stated overload and environmental conditions.
The Explain card
- Plain English
- The output current rating is how many amps the drive can deliver to the motor continuously, at its stated overload, temperature and switching frequency. It is the number that actually sizes a drive.
- Example
- A motor nameplate reads 27 amps full load. A drive rated 30 amps continuous covers it with a little margin, and a drive rated 24 amps will run warm and trip on hot days.
- Why it matters
- Horsepower on a drive label is a rough class, and two 20 horsepower motors can have different currents. Match amps to amps, then check the overload the application needs and whether the derating for altitude or carrier frequency eats the margin.
- Hook
- Amps, and then everything else.
Where it sits in the deck
Phase 9: VFD Ratings, Sizing, and Motor Data
Nameplate arithmetic, where the currents, voltages and duty ratings decide whether a drive can actually run the motor you bolted it to.
