plot to dwf with the right scale

Hello, i want to plot a sheat in 1/200 scale, but i need the drawing with the real measures. for exemple: i have a road with 6meters in realaty but if i confirm the measure after i plot to dwf, the measure of the road its diferent them 6 meters ( i tried diferents scales but it is impossible to reach the correct value). The town hall demands the drawings in the real scale (6meters in realaty must be 6meters in the paper ) independent of the scale that the drawing is.