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What is the magnetic power generated when a 7.5 HP motor is run.?

When we supply electricity to the 7.5 HP motor, the coils will be magnetised. What is the magnetic power in the coils when the motor runs on full speed.

Public Comments

1. I'd need more info before I could answer this question. There are many different types of motors and, although they all use the same principle, they work in many different ways. Some use DC current, some AC. Some use a physical commutator and switch power to the coils via brushes and some use electronic means to do the switching, some use permanent magnets on the stator and wire coils on the rotor, some switch this around, some use wire coils on both the stator and rotor. On top of all this, they work with a range of voltages and currents. The amount of magnetic flux depends on the strength of the permanent magnets used (if they are used), the type of core used (eg. iron) and whether or not it has a core at all (some don't), the number of coils, the amount of current, etc., etc. In other words, it's a very complex question and without quite specific details about the motor it's not really possible to work out how much magnetic flux (or power) is being generated by the coils.
2. I don't fully understand the problem. Are you trying to exploit or enhance the motors ability to perform as an electromagnet? The magnetic field generated by the motor is directly proportional to the amount of current through the coils, as well as the thickness and number of windings in the coil. The resultant force is exerted perpendicular to the coils, described in the equation below F = qV x B Where F, q, and B are directional vectors. F itself is calculated as the cross product between q ( the electric charge of the particle ), v ( the velocity vector of the particle ), and B ( the magnetic field ). Because this is a cross product, the force is perpendicular to both the motion of the particle and the magnetic field. We'll need to convert the horsepower measurement into an energy we can use. Let us use what we know: 1 horsepower = 746 watts 7.5 horsepower = 7.5 watts x 746 watts/hp = 57,050 watts ( Notice the horsepower units cancel each other out ) Power = voltage x amps = 480v ( 2 phase ) x amps, solve for amps 57,050 = 480 x amps amps = 57,050/480 = ~119amps Returning to our formula F = ( B^2 x A ) / μo where, F is the force in newtons ( or pounds per foot ) B is the magnetic field in teslas A is the area of the pole faces in square meters ( ~6 sq meters ) μo is the permeability of free space ( 398kPa ) Also, in a closed magnetic circuit B can be defined as: B = ( u x N x i ) / L where, N is the number of turns of wire around the electromagnet i is the current in amperes L is the length of the magnetic circuit μ = μo x μr is the permeability of the magnetic core μr is the relative permeability of the electromagnets core Backsubstituting for B results in a final equation F = ( ( u x N x i ) / L )^2 x A ) / μo I don't have these dimensional values available to me. But I've given you everything you need to solve the equation. PS - In order to build a strong electromagnet, a short magnetic circuit with large area is preferred. Most ferromagnetic materials saturate around 1 to 2 teslas.