How i can calculate the input power of motor using the shaft diameter of motor?

 

Ibrahim Awad... rather than leave this question unanswered, perhaps you can expand your query!

(1) Do you mean, "Given a shaft diameter, say 'X' mm, then, what is the maximum Hp of the motor in which the shaft is fitted?"

Or,

(2) Do you mean, "Given a shaft dimension, say 'X' mm, and a the rotational speed, say 'Y' rpm, then, what is the maximum realizable torque, hence Hp, and eventually the motor's correspondent input power?"

Regards, Phil Corso (cepsicon[at]aol[dot]cpm)

 

i mean, "Given a shaft diameter, say 'X' mm, then, what is the maximum Hp of the motor in which the shaft is fitted?"

 

Ibrahim,

yours is a tough question... right up there with, "Can you describe a ratchet without using your hands?"

Your question is best answered by starting with a brief discussion of Motor-Frame-Designations that cover a host of standard, off-the-shelf motors. Manufacturers use standards based on motor dimensions. For example, motors manufactured in the USA apply the NEMA Standard, or The National Electrical Manufacturers' Association! The Standard covering some 50 Frame-Size-Designations (FSD) is based on about 15 principal dimensions, including shaft-diameter, center-line height of the shaft, etc, to motor-mounting hole-size and location.

Literally, then, the number of different sizes can reach several thousand. However, from a practical view point, there are relatively few. For example a shaft-diameter of 3/8ths of an inch (~10 mm) is found in only one (1) FSD. Conversely, a diameter of 3-3/8 inches (~86 mm) can be found in ten (10) FSDs.

The answer you seek is still unavailable! While a good start, knowledge of just shaft-diameter is still not enough. You must also know rotational-speed, supply-voltage, as well as type of enclosure, i.e., open-frame, drip-proof, totally-enclosed, etc.

Regards, Phil Corso (cepsicon [at] aol [dot] com)

 

That will depend on the speed HP = torque x RPM. Why not just search a motor frame size chart?

Roy