UL1574表面轨道灯测试天花

53.4.1 The track lighting system assembly to be tested is to consist of three intercept connector samples, two feed connector samples, one luminaire assembly sample, and four 20 inch (0.51 m) long sections of track. The connectors and luminaire assembly samples are to be of the models with the highest measured resistance as specified in 53.2.1. The electrical fittings are to be assembled as shown in Figure 53.1 and mounted to one side of a plywood test ceiling consisting of 1/2 inch (12.7 mm) thick Grade A – C or A – D plywood of such dimensions that the plywood extends at least 1 foot (305 mm) beyond each portion of the network and luminaire assembly. A 4 inch by 1-1/2 inch deep octagonal trade size standard metal outlet box is to be secured inside a wooden box by screws through the back of the outlet box. The wooden box is to be constructed of 2 inch by 4 inch trade size pine. The inside dimensions of the wooden box are to be 4 inches by 3-7/8 inches by 1 inch (102 mm by 98.4 mm by 25.4 mm). The wooden box is to be mounted to the plywood over a 4 inch by 4 inch opening. Each section of track is to be secured to the plywood by two wood screws through openings, each of which is:

a) 3 inches (76.2 mm) from the end of a track section; or b) 1/2 inch from the connector in the end of the track; whichever is the greater distance from the end. The feed connector is to be mounted to or over the outlet box. The side of the plywood to which the track system is not mounted is to be completely covered with a layer of foil-faced R19 glass fiber batt insulation with the non-foil-faced side of the insulation facing the plywood test ceiling. The plywood surface is then to be suspended or supported so that a simulated ceiling mounting of the track assembly results.  

Exception: If, as a result of measuring the resistance of the intercept connectors, a right or left turn intercept connector is determined to have the highest resistance and is to be subjected to the grounding resistance test, two right and one left intercept connector samples may be tested in the test assembly.