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# How to Read Motor Performance Chart/Sheet?

05/06/2012 3:00 AM

I had tried searching in forum, but couldnt find how to read it exactly. I know its a lehman's 'Q'. Please help me through it.
Here is the motor chart. The black spot within is what i have plotted provided RPM & Power.What would be the motor torque & efficiency??!!is it between 40-45% & 100NM???????!!!!! please help!

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#1

### Re: How to read motor performance chart/sheet??

05/06/2012 3:41 AM

The graphics display on CR4 tends toward grayed-out images with tiny text and numbers, so the curves are unreadable. Power = constant x torque x rpm, where "constant" depends on the chosen measurement units. The efficiency of 40-45% seems awfully low, although it is possible.

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#2
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### Re: How to read motor performance chart/sheet??

05/06/2012 4:38 AM

Yup!! Actually the efficiency will increase if demand for power putput increases acc. to graph!! sounds weird!!

Is it possible!?!?

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#3
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### Re: How to read motor performance chart/sheet??

05/06/2012 5:38 AM

Generally, yes. (There may be exceptions toward the extremes of the graph.)

At lesser loadings, a larger fraction of total power goes toward fixed losses in the motor; hence the less efficiency overall.

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#4

### Re: How to Read Motor Performance Chart/Sheet?

05/06/2012 11:22 AM

Did you mean Leeson?

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#5
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### Re: How to Read Motor Performance Chart/Sheet?

05/06/2012 11:55 AM

Wats leeson?

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#6
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### Re: How to Read Motor Performance Chart/Sheet?

05/06/2012 12:00 PM

Never mind.

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