Wind Span And Weight Span 583j1j

What is the meaning of wind span and weight span? When looking at the transmission line profile view, the wind span is defined as half of the sum of adjacent spans. The weight span is defined as the distance from low point sag of one span to the low point sag of the next span. To clarify, these values have to do with loading of a ing structure (transmission line pole structure). with 3 structures in a row, there are 2 cable spans. One half of the sum of the 2 spans will give the wind span. This will be used to calculate the force applied to the structure due to a horizontal wind blowing on the conductors. Because the cable takes the form of a catenary curve when hung between 2 fixed points, there will be a low point between each of the structures. The distance between these low points will be the weight span for the middle structure. This value will be used to calculate the weight of the cable that the structure must .

The wind span is that on which the wind is assumed to act transversely on the conductors and is taken as half the sum of the two spans, adjacent to the .In order to take full advantage of towers located on elevated ground, it is usual to allow a wind span of 10 to 15 percent in excess of the normal span. This additional strength can be used in taking a samll angle of deviation on an intermediate tower, where the actual wind span is less than the design wind span. The angle of deviation to be taken in such cases is approximately given by: θ =( wl /π T )x x180

Where w = total ind load per unit run of span length of all conductor carried by the tower, l = difference between the wind span used for design and the actual wind span, and T = the total maximum working tension of all conductors carried by the tower. The weight span is the horizontal distance between the lowest point of the conductors, on the two spans adjacent to the tower . The lowest point is defined as the point at which the tangent to the sag curve, or to the sag curve produced, is horizontal. The weight span is used in the design of cross-arms.