4 pole vs 6 pole 1ph motor for fan

[Tony Way]

Being asked to install a 500mm plus diameter ventilation fan on a 1ph system.

What are the benefits/considerations between 4 pole and 6 pole motors?? Because I don't have a clue!!

 

[mechelec]

If its an induction motor syncronous speed will be affected by no of pole pairs ie

syncronous speed = (frequency of supply * 60)/no of pole pairs

 

[pushrod]

the 6 pole will run more slowly, at 2/3 the speed of the 4 pole one