High-Altitude Considerations for Electrical Power Systems and Components

The design and application of electrical systems at elevations in excess of 1000 m (3000 ft) requires knowledge of the effects of atmospheric conditions on each particular component. Failure to understand adequately and include the effects of high altitude in the design and application of the equipment may result in its poor performance, premature aging, and/or failure. The relationship of relative air density and altitude is discussed, followed by the effects of altitude on electric power system components. Along with the discussion of the effects of high altitude on each component are suggestions or solutions to the high-altitude problem. Although the subject deals with high-altitude applications of equipment, the performance of equipment from sea level to 1000 m may be affected by the relative air density. Since the relative air density decreases at a rate of approximately one percent per 100 m above sea level, the operation of any piece of equipment which is dependent on the air density will be different at 3300 ft compared to sea level. This subject is discussed so that independent conclusions may be drawn.