Required discharge amount when applying UHF partial discharge transformer to detect precisely calibrated, the paper model design, build relationships UHF signal energy and discharge capacity, through visual indicators to determine the amount of partial discharge, assessing equipment operation situation.In this paper, the partial discharge source model as a transmitting antenna processing, and the introduction of Friis transmission equation, the calculation is equivalent to the antenna transmission. Experimental data measured by the statistical model built discharge collectible display, UHF signal energy and the discharge amount quadratic relation is consistent with the theoretical model.