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How Can I calculate the rated speed in Dc motor?

How Can I calculate the rated speed in Dc motor?

How Can I calculate the rated speed in Dc motor?

(OP)
Dear all,
First of all, I would like to know what are the difference between maximum motor speed and rated speed?

Secondly, how can I calculated the rated speed if I know the speed trajectory for the load in order to choose proper motor?

For example, to calculate the rated torque it will follow the following equation:
T(rated)=sqrt[(Integarion of (T(t)^2.dt))/cycle time]

What about the rated torque?

RE: How Can I calculate the rated speed in Dc motor?

Rated speed is speed at full load with rated voltage applied.
Maximum speed is a mechanical limit.
A DC motor may be turn at more than rated speed due to being overdriven by the load, by too high an applied voltage, by too low a field voltage, or by loss of field.
Some motors such as series motors and some compounded motors may overspeed with loss of load.
Use rated horsepower at rated speed to calculate rated torque.
Check the catalog for information on speed regulation.

Bill
--------------------
"Why not the best?"
Jimmy Carter

RE: How Can I calculate the rated speed in Dc motor?

Typically the maximum speed is highest speed that the motor can operate safely.  The rated speed is established by the manufacturer by arbitrary methods that may include applied voltage, applied torque, output power, efficiency range etc.  I don't believe that you can calculate "rated" anything without knowing the criteria used by the manufacturer to rate their product.  You would definitely need to include the temperature to determine the "rated" torque and know the class of insulation system used as well as the thermal characteristics of the motor.  I may not have understood your question though so perhaps someone else can help.

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