Question

How many poles should the motor have, and how does this relate to the motor's speed?

Answer

Using a four-pole motor will work for most applications. Hitachi inverters can be configured to operate motors with 2, 4, 6, or 8 poles. The greater the number of poles, the slower the base motor speed will be, but it will have higher torque at the slower speed.

The number of poles that a motor has determines it's speed at a particular frequency. The synchronous speeds for three phase 60 Hz motors are as follows: 2 pole = 3600 rpm; 4 pole = 1800 rpm; 6 pole = 1200 rpm; 8 pole = 900 rpm.

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FAQ Subcategory: None

This item was last updated on 2007-09-25
Document ID: 296

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