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Jon Elson Jon Elson is offline
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Default RPM of variable speed DC Motors

Louis Ohland wrote:
After some web surfing, with HP being the same on a permanent magnet
DC motor, is a lower RPM for the given HP better than a higher RPM for
the same HP?

Motor A: 1HP, 90V, 2500 RPM, 10.7A 4.28A per 1,000 RPM
Motor B: 1HP, 90V, 1750 RPM, 9.2A 5.26A per 1,000 RPM

Since I'm a recovering college graduate, does this mean more kick per
RPM by the lower speed drive?

Motor B has more torque at rated current. The A/RPM is
meaningless, derived by dividing the rated full-load current by
the rated RPM. One interesting observation, though, is that
motor B is 16% more efficient than motor A, since they both
deliver 1 HP at the same voltage, but B draws a lot less current.

Jon