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How do I Calculate Power From VFD?

In physics, the power of a force is the rate at which it performs work. Work is equivalent to the magnitude of the force, in Newtons, and the distance an object is displaced by the applied force. Power is equal to work of a force multiplied by the velocity of the object on which the force working. This is equivalent to saying (P)ower = (V)elocity * (D)isplacement * (F)orce. Since velocity equals (displacement / change in time) plus direction, the equation becomes: P = F * (D / "t) = F * V.

Instructions

- 1
  Note any angular inclination or declination of the forces acting on the object. For example, a force can act on an object horizontally with an inclination of 0 degrees or at any angle above or below the horizontal, such as 60 degrees above the horizontal (an inclination).
- 2
  Determine the velocity of the object under the influence of the forces by measuring the distance it travels over a set period of time then dividing the distance by how long it took to travel this distance. Velocity also includes the direction of motion; (+) for forward motion and (-) for reverse motion. Measure velocity in units of meters per second. For example, an object having moved 10 meters forward in 4 seconds has a velocity of: 10 meters / 4 seconds = +2.5 meters per second.
- 3
  Multiply the magnitude of a force acting on the object (measured in Newtons) by the velocity of the object and the cosine of the angular inclination or declination that the force is being applied. This gives you the applied power of the force. For example, for an object moving at 2.5 meters per second under the influence of a force of 8 Newtons angled upward at 60 degrees, the power equation becomes: P = (8 Newtons)(2.5 meters per second)(cos(60 degrees) = 10 watts.

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