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How do I determine what size motor I need

How do I determine what size motor I need

How do I determine what size motor I need

(OP)
Sorry for the non techie question here, just after some information and this forum seems to have the right brains to answer.

How do you determine the size/power of the motor required to perform the job.

As an example, say I wanted to fit an electric motor to move payload of say 1 ton, at speed to 15mph. Is there a basic way to determine this? I know I don't want the motor from a kids toy, but I also know i don't want to have a motor to launch a rocket...

Thanks for your help.

RE: How do I determine what size motor I need

You'll have to translate the load and linear speed to torque and RPM.  Is this a 1 ton load on wheels that you want to have move at a velocity of 15 mph?

RE: How do I determine what size motor I need


Start here. Engineer's Edge torque calculator for liner motion

Hint; You will need to determine the WK2 (moment of inertia) of the load. There is a separate link on that page to calculate that if you don't already know.

Once you know the required load torque, then use that and the speed to get a rough determination of HP using;

HP = T (lb-ft) x RPM/5250

Then starting with that info and the WK2 of the motor itself, make sure you can accelerate it fast enough for your needs using. If too slow, up the HP size and recalculate.

Sec. = WK2 x speed change in RPM / 308 x AAT

Where;
AAT = Average Accelerating Torque

AAT = [(FLT + BDT)/2] + BDT + LRT / 3

Where;
BDT = Break Down Torque of the motor
FLT = Full Load Torque  "   "   "
LRT = Locked Rotor Torque " "   "

Or, go hire an engineer who already knows how to do this.

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