1、UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULNovember 27, 20061SUBJECT 523OUTLINE OF INVESTIGATIONFORTELEPHONE SERVICE DROP WIREIssue Number: 2November 27, 2006Summary of TopicsThis new issue of SU 523 is being issued through ULs electronic
2、publishing system to ensure format uniformity between the PDF andHTML versions of the document. No substantive changes have beenincorporated in the document.The UL Foreword is no longer located within the UL Standard. For informationconcerning the use and application of the requirements contained in
3、 thisStandard, the current version of the UL Foreword is located onULStandardsInfoNet at: http:/ 2006 UNDERWRITERS LABORATORIES INC.UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULNOVEMBER 27, 2006SUBJECT 5232No Text on This PageUL COPYRIGHTED
4、 MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULCONTENTSGENERAL1 Scope .42 Units of Measurement .4CONSTRUCTION3 Materials and Workmanship 44 Single Pair .44.1 Conductors 44.2 Insulation and jacket 54.3 Single strength member .75 Multiple Pairs .75.1 Conduct
5、ors 75.2 Insulation and jacket 75.3 Support wire .7PERFORMANCE6 Carbon-Arc and Water-Spray Exposure Test .87 Cold Bend Tests 97.1 Cold wind onto cold mandrel .97.2 Unwind after cold soak 98 Heat Shock Test 99 Flow Test .1010 Static Load Test 1011 Impact Test 1112 Crushing Tests .1112.1 Wire between
6、two flat steel plates 1112.2 Wire between one flat plate and a round rod 1113 Dielectric Voltage-Withstand Tests 1213.1 Single-pair wire 1213.2 Multiple-pair wire .1214 Insulation Resistance Tests 1214.1 Single-pair wire 1214.2 Multiple-pair wire .1215 Mechanical Water Absorption Test 1316 Flame Tes
7、t .13MARKINGS17 Wire Markings 1318 Tag, Reel, or Carton Markings .13NOVEMBER 27, 2006 SUBJECT 523 3UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULGENERAL1 Scope1.1 These requirements cover single-pair and multiple-pair telephone drop wires in
8、tended for use asoverhead conductors that extend telephone circuits (1) from the last utility pole or other outdoor supportto the protector(s) within the building or other structure served, and (2) between buildings or otherstructures on the premises served. These wires are for use in accordance wit
9、h Article 800 of the NationalElectrical Code ( NFPA 70).1.2 These requirements do not cover telephone cable for underground duct applications or direct burial,nor do they cover coaxial telephone cable or distribution wire for telephone service.2 Units of Measurement2.1 In addition to being stated in
10、 the inch/pound units that are customary in the USA, each of therequirements in this outline is also stated in units that make the requirement conveniently usable incountries employing the various metric systems (practical SI and customary). Equivalent although notnecessarily exactly identical resul
11、ts are to be expected from applying a requirement in USA or metricterms. Equipment calibrated in metric units is to be used when a requirement is applied in metric terms.CONSTRUCTION3 Materials and Workmanship3.1 Only materials that are acceptable for the particular use shall be employed in a wire.
12、Wires shall bemade and finished with the degree of uniformity and grade of workmanship that are practicable in awell-equipped factory.3.2 Each material used in a wire shall be compatible with all of the other materials used in the wire.4 Single Pair4.1 Conductors4.1.1 In the integral PVC constructio
13、n containing a single centrally located strength member, two No. 24AWG uncoated solid copper conductors, laid parallel. Otherwise, one pair of No. 18 or 17 AWG solidcopper-coated steel wires, laid parallel, having a nominal conductivity of 30 percent IACS.NOVEMBER 27, 2006SUBJECT 5234UL COPYRIGHTED
14、MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL4.2 Insulation and jacket4.2.1 In the integral construction, the insulation an jacket shall be of PVC or of EPDM rubber. Specimenstaken from the finished wire and tested for physical properties as described in
15、sections 400-480 of theReference Standard for Electrical Wires, Cables, and Flexible Cords, UL 1581 shall comply with Table 4.1(PVC) or 4.2 (EPDM).Table 4.1Physical properties of PVCCondition of specimens at time ofmeasurementMinimum acceptable ultimateelongation (1-in or 25-mm benchmarks)Minimum ac
16、ceptable tensile strengthUnaged 225 percent 1800 lbf/in2or(2-1/4 in or 56.3 mm) 12.4 MN/m2or1240 N/cm2or1.27 kgf/mm2Aged for 168 h in a full-draft circulating-air oven at 100.0 1.0C (212.0 1.8F)60 percent of the result with unagedspecimens85 percent of the result with unagedspecimensTable 4.2Physica
17、l properties of EPDM rubberCondition of specimens at time ofmeasurementMinimum acceptable ultimateelongation (1-in or 25-mm benchmarks)Minimum acceptable tensile strengthUnaged 300 percent 1500 lbf/in2or(3 in or 75 mm) 10.3 MN/m2or1034 N/cm2or1.05 kgf/mm2Aged in an oxygen bomb for 168 h at80.0 1.0C
18、(176.6 1.8F) and agauge pressure of 300 10 lbf/in2or2.07 0.07 MN/m2or 207 7 N/cm2or0.211 0.007 kgf/mm250 percent of the result with unagedspecimens50 percent of the result with unagedspecimensAged in an air bomb for 20 h at 127.01.0C (260.6 1.8F) and a gaugepressure of 80 3 lbf/in2or 0.55 0.02MN/m2o
19、r 55.2 2.1 N/cm2or 0.0560.002 kgf/mm250 percent of the result with unagedspecimens50 percent of the result with unagedspecimens4.2.2 In the nonintegral construction, the insulation shall be of NR (natural rubber) or SBR rubber or ablend of the two and the jacket shall be of neoprene. Specimens taken
20、 from the finished wire and testedfor physical properties as described in sections 400-480 of the Reference Standard for Electrical Wires,Cables, and Flexible Cords, UL 1581 shall comply with Table 4.3 (NR/SBR insulation) and 4.4 (neoprenejacket). In the nonintegral construction, there shall be a gl
21、ass, rayon, cotton or combination braid or wrapover the construction under the jacket.NOVEMBER 27, 2006 SUBJECT 523 5UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULTable 4.3Physical properties of NR/SBR rubberCondition of specimens attime of
22、measurementMaximum acceptable set inrecovery test (1-in or25-mm bench marksstretched to 3 in or 75 mm)Minimum acceptableultimate elongation (1-in or25-mm bench marks)Minimum acceptable tensilestrengthUnaged 25 percent (1/4 in or 6.2 mm) 350 percent (3-1/2 in or 87.5mm)1500 lbf/in2or10.3 MN/m2or1034
23、N/cm2or1.05 kgf/mm2Aged in an oxygen bomb for96 h at 70.0 1.0C (158.0 1.8F) and a gauge pressureof 300 10 lbf/in2or 2.070.07 MN/mm2or 207 7N/cm2or 0.211 0.007 kgf/mm2Not measured 65 percent of the result with unaged specimens if the sum oftensile plus elongation percentages is at least 140 percent.O
24、therwise 70 percent of the result with unaged specimensTable 4.4Physical properties of neopreneCondition of specimens attime of measurementMaximum acceptable set inrecovery test (1-in or25-mm bench marksstretched to 3 in or 75 mm)Minimum acceptableultimate elongation (1-in or25-mm bench marks)Minimu
25、m acceptable tensilestrengthUnaged 19 percent (3/16 in or 4.7mm)300 percent (3 in or 75 mm) 1800 lbf/in2or12.4 MN/m2or1240 N/cm2or1.27 kgf/mm2Aged in an oxygen bomb for96 h at 70.0 1.0C (158.01.8F) and a gaugepressure of 300 10 lbf/in2or2.07 0.07 MN/mm2or 2077 N/cm2or 0.211 0.007kgf/mm2Not measured
26、65 percent of the result with unaged specimens if the sum oftensile plus elongation percentages is at least 140 percent.Otherwise 70 percent of the result with unaged specimensAged in a full-draft circulating-air oven for 168 h at 70.01.0C (158.0 1.8F)Not measured 70 percent of the result with unage
27、d specimensAged in ASTM oil No. 2afor18 h at 121.0 1.0C (249.81.8F)Not measured 60 percent of the result with unaged specimensaASTM oil No. 2 is medium-swelling and of a petroleum base. Measured at 210.0F (98.9C), its Saybolt Universal viscosityis 1005 s (443-490 m2s at 310 K). Its aniline point is
28、93.03.0C (199.45.4F). Its open-cup flash point is 475.010.0F(246.15.6C).NOVEMBER 27, 2006SUBJECT 5236UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM UL4.3 Single strength member4.3.1 In the integral PVC construction that contains No. 24 AWG cond
29、uctors, longitudinal strength shallbe provided by a single member consisting of cabled steel strands or of bundles of glass-fiber yarn. Thestrength member shall be contained within the body of the integral PVC insulation and jacket an shall belocated midway between and in the plane of the two conduc
30、tors.5 Multiple Pairs5.1 Conductors5.1.1 Two or more twisted pairs of No. 22 AWG solid copper.5.2 Insulation and jacket5.2.1 Each conductor shall be insulated with a 0.011 in or 0.23 mm minimum average wall (0.010 in or0.25 mm minimum at any point) of PE complying with Table 5.1. Over the mm minimum
31、 average (0.004in or 0.10 mm minimum at any point) covering of PVC whose physical properties are not specified (thetwisted pairs (cable core) shall be wrapped with a polyester tape measuring 0.001 in or 0.025 mm or moreminimum at any point applied longitudinally with an overlap of at least 1/8 in or
32、 3 mm. The wrapped coreshall be jacketed with a 0.040 in or 1.02 mm minimum average wall (0.032 in or 0.81 mm minimum at anypoint) of PVC complying with Table 4.1.5.3 Support wire5.3.1 Paralleling the jacketed cable and connected to it by a web shall be a steel support wire coveredwith PVC that comp
33、lies with Table 4.1 and is integral with the web and the cable jacket.Table 5.1Physical properties of PECondition of specimens at time ofmeasurementMinimum acceptable ultimateelongation (1-in or 25-mm benchmarks)aMinimum acceptable tensile strengthUnaged 350 percent (3-1/2 in or 87.5 mm) 1400 lbf/in
34、2or9.65 MN/m2or0.984 kgf/mm2Aged in a full-draft circulating-air ovenfor 48 h at 100.0 1.0C (212.0 1.8F)75 percent of the result with unaged specimensaPE (polyethylene) with a density of 0.93 g/cm3(930 kg/m3or higher is to be tested at a speed of 2.0 0.02 in/min or 505 mm/min. PE with a density lowe
35、r than 0.93 g/cm3(930 kg/m3) is to be tested at a speed of 20 1 in/min or 500 25mm/min. A quick, rough check of whether the density of a given piece of PE is below 0.93 g/cm3can be made byimmersing the insulation in olive, cottonseed, or coconut oil while the oil and PE are at room temperature (25C
36、or 77Fmaximum). Material with a density lower than 0.93 g/cm3(930 kg/m3) rises to the surface an floats within a minute or so.NOVEMBER 27, 2006 SUBJECT 523 7UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FURTHER REPRODUCTION ORDISTRIBUTION WITHOUT PERMISSION FROM ULPERFORMANCE6 Carbon-Arc and Water-Spra
37、y Exposure Test6.1 The ratio of the average tensile strength and ultimate elongation of five conditioned specimens of theintegral jacket and insulation, or of the nonintegral jacket, to the average tensile strength an ultimateelongation of five identical unaged specimens shall not be less than 0.85
38、when the specimens are insections 400 480 of UL 1581 after 300 h of exposure to water spray and radiation from carbon arcs asdescribed in 6.2 6.7.6.2 Five complete specimens of the finished wire are to be mounted vertically in the specimen drum ofcarbon-arc-radiation and water-spray exposure equipme
39、nt that is similar to the Type D apparatusdescribed in the American Society for Testing and Materials Standard Recommended Practice forOperating Light-Exposure Apparatus (Carbon-Arc-Type) with and without Water for Exposure ofNonmetallic Materials ( ASTM G 23-81). The specimens are to be centered be
40、tween the top and bottomof the drum. The drum of the apparatus used is to be 31 in or 787 mm in diameter (the diameter from theface of a specimen on one side of the drum to the face of a specimen on the opposite side of the drumis to be about 30 in or 762 mm), 17-3/4 in or 451 mm high, and is to rev
41、olve at the rate of 1 r/min. Theapparatus is to have arcs between two set of vertical carbon electrodes that are clear globes ofheat-resistant optical glass (9200-PX Pyrex glass or its equivalent) that is opaque at wavelengths shorterthan 2750 angstrom units or 275 nm and whose transmission improves
42、 to plane is to bisect both arcs andis to intersect each specimen at its midpoint. The globes are to be replaced after whichever of the globesof pronounced discoloration, milkiness, or both. The globes are to be washed with detergent and water,rinsed thoroughly, and air dried at room temperature imm
43、ediately before each days operation.6.3 Radiation from the arcs is to be kept by positive non-makeshift means from reaching persons withinsight of the apparatus. Ventilation is to be provided to keep the products of combustion in the arcs fromcontaminating the specimens, and these products and the o
44、zone generated are to be kept from being inany significant concentration in air breathed by persons.6.4 Means are to be provided to enable each specimen to pass through a fine spray of water once duringeach revolution of the drum in the cycle of 3 and 17 min repeated as noted in 6.5. The water is to
45、 be clean,its pH is to be 6.0 8.0, its temperature is to be 16.0 5.0C (60.0 9.0F), and the water is not to berecirculated unless these conditions are maintained. While the arcs are in operation but spray is off, theequilibrium black-panel temperature of the drum is to be 63 5C (145 9F).6.5 With the
46、drum revolving continuously at 1 r/min, with the arcs operating continuously and carrying acurrent of 15.17 A apiece at a drop in rms potential of 120 145 V, and with prudent attention to he riskto eyesight and to the other health risks presented by the arcs, the spray is to be operated for 3 min on
47、and 17 min off. This cycle is to be repeated six times resulting in operation with each specimen beingsubjected to spray with radiation from the arcs for a total of 102 min and to the wate spray with radiationfrom the arcs for a total of 18 min resulting in turn in a total elapsed operating time of
48、300 h. The apparatusis to be turned off after the total operating time of 300 h. the specimens are to cool to room temperaturebefore being removed from the drum for testing.6.6 The conductors, nonintegral insulation, wrap, and support wire are to be removed from the fiveconditioned specimens and fro
49、m five identical unaged specimens. Die-cut specimens are to be preparedfrom the integral jacket and insulation or the nonintegral jacket conditioned in the apparatus and are toinclude the portions of the jacket closest the arcs. The surfaces facing the arcs are not to be buffed,skived, or planed away. Similar die-cut specimens are to be prepared from the unaged specimens.NOVEMBER 27, 2006SUBJECT 5238UL COPYRIGHTED MATERIAL NOT AUTHORIZED FOR FUR
