Motor Selection Criteria

Op forgot to add...

"Because I do not have a clue how to do this, nor do I want to learn how. But I do need to finish a quote to give to my boss so we can underbid our competition who does hirer people who do know how to do this. So help me quickly please."

Gimme a break.

A detailed posting has been made on motor selection for fan recently.Pl go my comment in detail.Apart from Horse power main factor to be considered in motor selection is the Fan GD sq ,and application Check using Motor and Fan Speed -Torque curve if u intend using a cage motor.In the application check you have to calculate the acceleration time and compare with motor's stall withstand time hot and cold which should be more than acceleration time.Best will be to use a Slip ring motor and a resistance starter which can give sufficient starting Characteristic.If environment whre motor will be located is is polluted then use motor with IPP55 Enclosure .

You already have a 10% margin.The BHP consideration depends on how the fan will be run.Whether it will run at full load and what is the speed variation.Are u using any device for speed variation?Normally these fans work between 66% to 100% speed.So 100% BHP will be ideal .Full fan running details will have to be studied to take the final decision.