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94 <br />steeper the vertical aiming angle. The steeper the aiming angle, the less spill light and glare that <br />result. The effect of mountng height on spill and glare can be seem in the example below. <br />Exam 1p a #1: A single NEMA 4M 150OW Light - Structure Green fixture is aimed to the center <br />of a soccer field. The only difference in this example is the mounting height; all other <br />parameters (aiming point, pole setback, fixture type, field size, etc.) remain the same. In the <br />illustration, the edges of the light beam represent the rays at which the beam's intensity is 10% <br />of the maximum candlepower. <br />max OF MM <br />t � � <br />'LW Rva I urn (WW W S=W FW <br />ma W Ma <br />xrw uaa wax <br />isa.• (+sa,.) mob � ma a M noo <br />As shown in example #1, the taller mounting height produces a steeper aiming angle which <br />distributes more light from the fixture onto the field, thereby decreasing the spill light and glare <br />for the nearby house. <br />B. Pole Setback <br />The closer the setback, or closer the pole is to the edge of the field, the steeper the vertical <br />aiming angle. The steeper the aiming angle, the less spill light and glare that result. The effect <br />of different setbacks can be seen in the example below. <br />Exam field. <br />a #2: A single NEMA 4M 150OW LSG fixture aimed to the center of a soccer field. <br />The only difference in the example is the setback of the poles; all other parameters (aiming <br />point, mounting height, fixture type, field size, etc.) remain the same. <br />.�FAW <br />W rue <br />�r� SEIBCII <br />100 mA: ?1010 <br />masWKW <br />AW tss.0 xot soau ms SM UM mom mw <br />1500' taIW " W W m0E ff "FM <br />As seen above in example #2, the pole with the closer setback produces.a steeper aiming angle <br />which directs more light from the fixture onto the field, thereby decreasing the spill light and <br />glare for the nearby house. <br /># TB001S <br />Page 2 of 3 <br />