On Tuesday, April 4, 2017 at 9:04:39 AM UTC-4, Colonel Edmund J. Burke wrote:
It's the angle of the dangle.

he's not kidding, it's a lot to do with the angle of the blades in the
centrifugal blower.

There are different portions of the curve.

One test is how much suction it can create with no air flow, like when you put your hand over the opening

The other extreme is how much air flows when there is no restriction.

You will notice that most vacuum cleaners will speed up and draw less current when you block the airflow.

So there is no simple answer. But everything else being equal, a more powerful motor can pull more dirt and will draw more current.

Google centrifugal pump or centrifugal blower design for the gory details.

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