UL 651-2011 pdf download

UL 651-2011 pdf download.Schedule 40，80，Type EB and A Rigid PVC Conduit and Fittings.
6.14.6 Each sample to pass through a fine spray of water once during each revolution of the drum in the repeated cycle of 3 and 17 minutes as noted in 6.14.7. The water is to be clean, its temperature 16.0 ±5.0°C (60.0 ±9.0°F) and pH 6.0 – 8.0. The water is not to be recirculated unless these conditions are maintained. While the arcs are in operation but the spray is off, the equilibrium blackpanel temperature of the drum Is to be 63 ±5°C (145 ±9°F).
6.14.7 With the drum revolving continuously at one revolubon per minute. the arcs operating continuously and carrying a current of 15 — 17 A each at a drop In potential of 120 — 145 V rms. and with prudent attention to eyesght and other health risks presented by the arcs, the spray is to be operated for 3 minutes on and 17 minutes oft This cycle is to be repeated six times so that each sample is subjected to radiation from the arcs for a total of 102 minutes and to the water spray with radiation from the arcs for a total of 18 minutes, This sequence is to be repeated resulting in a total elapsed operating bme of 1440 hours. Fifteen of the samples are to be removed after 720 hours, another 15 samples are to be removed after 1080 hours, and the remaining 15 samples are to be removed after 1440 hours. The apparatus Is to be turned off to remove each set of 15 samples, and all of the samples are to cool to room temperature before any samples are removed from the drum.
6,14.8 Each unaged and conditioned sample is to be notched to the dimensions indicated it’ Figure 6,9 on a milling machine, engine lathe, or similar machine tool having an accuracy of at least 0.001 inch or 0.01 mm. The cutter and feed speeds and the cutting action are to produce the notch without alteration of the PVC. Under 60 power magnihcation, each completed notch is to show as a clean and sharp cut without any nicks, cracks, or thermal deformation, having the angle and radius indicated in Figure 6.9. A micrometer having an anvil contoured to fit in the notch is to be used to verify that the depth of PVC under the notch Is within the limits indicated in Figure 6.9. The notched surface is to be within 0.001 inch 0.025 mm) of being parallel to the other long machined surface and is to have less than 0.002 inch (0.050 mm) of twist. The plane bisecting the notch is to be within 2 degrees of being perpendicular to the notched surface. A specimen that departs from one or more of these requirements may be machined further to make it comply. A specimen is to be discarded after this preparation if either or both of its curved surfaces (the original inside and outside surfaces of the rigid PVC conduit) show any scratches or other defects. The width of each specimen retained Is to be measured at the notch and recorded to the nearest 0.001 inch or 0.01 mm.
6.14.9 The notched specimens are to rest in still air at a temperature of 23.0 ±2.0°C (73.4 ±3.6°F) and humidity of 50 ±5 percent for 40 hours or longer before being tested. The test Is to be made within this range of temperature and humidity.
6.14.10 The test apparatus and Its calibration and A and B energy-loss factors are to be in accordance with the Standard Test Method for Determining the Izod Pendulum Impact Resistance of Plastics. ASTM D 256.
6.14.11 At least 10 each of the unaged specimens and specimens prepared from samples conditioned for 720 and 1080 hours are to be tested in close succession after completion of the 1080 hours of conditioning without waiting for completion of the conditioning of the 1440-hour samples. If the results after 1080 hours are within the limits indicated in Table 6.4, conditioning of the 1440hour samples may be discontinued and the 14-4-0-hour samples may be discarded.
6.14.12 Each specimen in turn is to be positioned precisely and clamped rigidly (tightly but not to the point of damaging the specimen) in the vise as shown in Figure 6.10, and the pendulum is to be released The lzod impact strength of each specimen and the average Izod impact strength of each group ol specimens (unaged, 720 hour, 1080 hour, and possibly 1440 hour) are lobe determined as described in the Standard Test Method for Determining the hod Pendulum Impact Resistance of Plastics, ASTM D 256. The average lzod impact strength of the unaged specimens shall not be less than 0.5 ftibflincti (27 j?m) of notch width (see 6.14.1). The average Lzod impact slrengths of the specimens prepared from samples conditioned longer than 720 hours shall comply with Table 6.4.