STANDARD SPECIFICATION FOR SIGNAL CABLE. A. This Specification provides for single and multi-conductor insulated and jacketed cable for

Size: px

Start display at page:

Download "STANDARD SPECIFICATION FOR SIGNAL CABLE. A. This Specification provides for single and multi-conductor insulated and jacketed cable for"

Rosanna Magdalene Barber
5 years ago
Views:

1 STANDARD SPECIFICATION FOR SIGNAL CABLE 1.01 SCOPE A. This Specification provides for single and multi-conductor insulated and jacketed cable for installation in direct contact with the earth, in ducts, in air or any combination of these types of installations, and for single conductor insulated and jacketed wire for installation in wired housings, on circuits rated at volts. B. The Contractor shall include with his bid, preferably in the form of a cross-section drawing, a description of the cable he proposes to supply. The description shall include cable shape, construction, number of conductors and size, insulation thickness and type, insulation shield thickness, jacket thickness and type, and approximate cable weight per foot PURCHASE ORDER REQUIREMENTS The following information should be stated on the Purchaser's Order for each kind of cable: A. Total length in feet. B. Number of conductors. C. Gauge of conductors by AWG. D. Solid or stranded conductors. E. Length of cable on each reel. F. Special constructions such as armored, flexible, preassembled, aerial, shielding from inductive interference. G. Refer to this Specification. - 1-

2 1.03 QUALIFICATIONS A. The manufacture of cables in accordance with the requirements of this Specification shall be accomplished in compliance with a Quality Assurance Program that meets the intent of ASQC Standard C1-1968: General Requirements for a Quality Program. Such compliance shall assure the production of properly designed, well made, and thoroughly tested cable which will render long service life to SEPTA. Efficient methods of production, test, and product evaluation shall be used, but prime concern must be focused on the necessary formal quality requirements to insure that cable failure cannot be attributed to actions or lack of actions by the manufacturer. B. Material and workmanship of the wire and cable shall be of the highest quality assuring durability for the 40-year design life of the installation. C. The manufacturer offering cable designs and insulation materials for this service shall have a minimum of fifteen years reliable experience on vital circuit signal cables and shall meet the qualification tests specified herein QUALIFICATION TESTS The insulation shall be consistently uniform, and established as suitable for service at potentials to 15,000 volts. A. The dielectric strength stability shall be demonstrated by voltage aging a minimum of ten feet between terminals of a single conductor No. 14 AWG or larger size with 80 mil or thicker insulation, suitably finished. The cable shall be tested in free air with the ends appropriately terminated. - 2-

3 1. Apply one of the following stresses to voltage-age the sample: Test Voltage (volts/mil) Time years, or years, or years 2. Use the voltage-aged sample and apply 60 Hz voltage in 10 KV steps for five minutes at each step until breakdown. Start the test at the voltage-aging stress used in Paragraph No cable breakdown shall occur during the voltage-aging test and the same sample shall withstand a minimum test stress of 350 volts/mil on the step breakdown test in Paragraph 2. B. Thermal Aging The insulation shall be tests in a circulating air oven on 80 mil thick slabs and shall have an elongation not less than 50% after a minimum aging time of 25 hours at 136 C and 100 hours at 121 C. C. Moisture Resistance A single conductor No. 14 AWG or larger size with 80 mils or thicker insulation wall shall have at least 10 feet immersed in water at room temperature. The insulated conductor without any coverings over the insulation shall be continuously energized as follows: - 3-

4 DC Voltage (volts/mil) Time months, or months, or months, or months No insulation failure shall occur within the test period CONDUCTOR A. Solid Conductor: Conductor shall be soft or annealed copper coated with pure lead, lead alloy, or tin in accordance with ASTM B-189, or B33 for tin, lead, and lead alloy coated conductors. No factory splices or brazes shall be made in solid conductors after final drawing. B. Stranded Conductor: The conductor shall conform to ASTM B-8, latest revision, and tinned or lead alloy coated to conform to ASTM Designation B-33 or B-189, latest revision, where applicable INSULATION A. The conductor insulation shall be a vulcanized rubber compound meeting the dimensional, electrical, and physical properties in Appendix "A". B. The insulating compound shall be clean and free stripping, leaving the coated conductor unimpaired and ready for soldering. - 4-

5 C. Part 3 of ICEA Standard S does not apply to this Specification. D. Direct burial multi-conductor constructions will have insulated thicknesses per AAR Class A in Table I. E. Aerial multi-conductor and protected surface constructions will have insulation thicknesses per AAR Class B in Table I. F. The average thickness of insulation shall be not less than the specified thickness. The minimum thickness at any point shall be not less than 90% of that specified. G. The insulation shall not crack during installation at temperatures as low as -40 F. TABLE I - MULTI-CONDUCTOR CABLE AAR CLASS CONDUCTOR SIZE, AWG THICKNESS OF INSULATION TEST VOLTAGES AC-60Hz 5 Minutes DC 10 Minutes A B 14 to 8 78 mils 100 V/Mil 300 V/Mil 6 to 2 94 mils 100 V/Mil 300 V/Mil 16 to 8 62 mils 100 V/Mil 300 V/Mil 6 to 2 78 mils 100 V/Mil 300 V/Mil 1.07 PRELIMINARY TESTING OF SINGLE CONDUCTOR A. Each length of insulated conductor prior to application of any outer coverings shall be random wound on reels and immersed in water for a minimum of twenty-four hours and then subjected to test voltages given above for five minutes without showing signs of puncture, overheating, or self-healing or punctures. Voltage shall be applied between conductor and water (ground). - 5-

6 B. Insulation Resistance Testing: Immediately after the AC Test in 1.07 above and while the insulated conductor is still submerged, an insulation resistance test shall be obtained on each length of conductor. The insulation resistance constant "K" shall not be less than 20,000 megohms ft. when corrected to 60 F. The following formula is intended to be used: R = K Log D 10d R = Insulation resistance in megohms per 1000 ft. at 60 F. K = 20,000 megohm constant ft. unit. D = Diameter over insulation. d = Diameter under insulation. C. DC Test: The DC Test may be applied prior to the AC Voltage Test or following the IR Test. Each coil or reel length of insulated conductor shall be subjected to and withstand the DC Test voltage shown in Table I ASSEMBLY A. Single Conductor Cables: 1. Single conductor aerial wire shall be made in accordance with construction shown in Table II and the completed cable on shipping reels shall successfully pass the test voltages indicated in Table I. - 6-

7 Conductor Size, AWG TABLE II Thickness of Insulation Thickness of HMW Black PE Layer 6 80 mils 50 mils 9 65 mils 50 mils mils 35 mils 2. Single conductor underground cables shall be made in accordance with the construction shown in Table III below. TABLE III Conductor Size, AWG Thickness of Insulation Thickness of HMW Black PE Layer 6 94 mils 62 mils 9 78 mils 62 mils B. Multi-Conductor Cables: 1. Aerial (above ground) cables shall be made by assembling individual conductors as specified per AAR Class "B" in Table I. Individual conductors shall be cabled helically with adjacent layers wound in opposite directions. Flame and moisture resistance fillers are to be used where necessary to assemble the cable into a tight cylindrical form and covered overall with a moisture resistance core tape. The outer jacket shall be made with the construction shown in the following Table IV. - 7-

8 TABLE IV These cables shall be cabled with moisture resistant fillers, core tape as needed, and a black polychloroprene or black chlorosulfonated polyethylene jacket overall with the following thicknesses: Calculated Core Diameter (Inches) Up to Minimum Average Jacket Thickness 62 mils to mils to mils to mils to mils 2. Underground Direct Burial Cables shall be made by assembling individual conductors as specified per AAR Class "A" in Table I. Individual conductors shall be cabled helically with adjacent layers wound in opposite directions. Fillers are to be used where necessary to assembly the cable into a tight cylindrical core. The core shall be covered with a shock-absorbing layer of moisture resistant core tape or an extruded elastomeric material if a bronze tape is not used, or layers of moisture resistance tape if bronze armor tape is used. When core tape or elastomeric material is used for a cushion layer, the thickness of the layer shall be in accordance with the following Table V. - 8-

9 TABLE V Calculated Core Diameter (Inches) Average Cushion Layer Thickness 0 to mils and larger 62 mils The outer jacket shall be made of extruded black low density high molecular weight polyethylene which shall be capable of meeting material Type I, Class C, Grade E5 of ASTM D-1248 with thickness in accordance with Table VI, Column A. When the cable is furnished with a bronze tape, the jacket thickness shall be in accordance with Table VI, Column B. TABLE VI Calculated Core Diameter (Inches) A Jacket Thickness B 0 to mils 47 mils to mils 62 mils to mils 78 mils to mils 94 mils to mils 109 mils 3. Conductor identification of multi-conductor cables shall be as follows: One conductor in each layer shall be suitably marked to serve as a tracer. The method used to distinguish the tracer shall be subject to the approval of SEPTA. The - 9-

10 assembly shall be capable of easy separation without damage to any of the conductors or loss of the tracer conductor identification. 4. Dry "spark" test shall be made during the process of cabling or immediately prior to any non-conducting covering operation. This test utilizes 10 KV, 3 khz or greater frequency to insure detection of damage to conductor insulation. C. Single Conductor Wire: 1. Single conductors for wired housing shall be made in accordance with Table VII. The conductor insulation shall meet the requirements of 1.06 A and 1.06 B above. The jacket shall be a black polychloroprene and shall meet the requirements of Table VII. The conductor shall be stranded and in accordance with 1.05 B above. TABLE VII Conductor Size AWG Insulation Thickness Jacket Thickness Tank Test KV AC 5 Min x 47 mils 15 mils x 47 mils 15 mils x 31 mils 15 mils x 31 mils 15 mils METALLIC COVERING A. Additional mechanical protection, if required, shall be specified as a 10 mil bronze tape helically wrapped so that at least a 20% overlap is obtained. A ten mil minimum helically applied compound filled tape having a minimum overlap of 12.5% shall be used in place of the cushion layer

11 B. When mitigation of electromagnetic interference is specified, shielding shall be provided in the form of a single layer of No. 10 AWG aluminum wire helically applied with a minimum of 95% coverage. The aluminum shield wire shall be cushioned from the conductors by a 10 mil helically applied compound filled tape having a minimum overlap of 12.5%. The shield wires shall be separated from the outer jacket by a binder tape IDENTIFICATION A. Multi-Conductor: Each length of cable shall be permanently identified with the manufacturer and year of manufacture, at intervals not more than one (1) foot, with a moisture resistant marker tape under the jacket and parallel to the longitudinal axis of the cable. B. Single Conductor Cable: It shall be identified by a printing, contrasting painted, printed, or manufacturer's color threads. The printing shall be on the outer jacket at intervals not to exceed three (3) feet. The color threads shall be placed under the outer jacket and parallel to the longitudinal axis of the cable FINISHED CABLE TESTS A. Each completed multi-conductor cable when on the master reels prior to cutting shall successfully pass two times the AC Test voltage levels indicated in Table I for one minute. This voltage to be applied between conductors utilizing mid-point grounded test transformer, with shields (if any) connected to ground. Metallic armored cable need not be immersed in water

12 1.12 INSPECTIONS AND TESTS A. SEPTA's Inspection: SEPTA shall have the right to make such inspection and tests as necessary to determine if the cable meets the requirements of this Specification. The Inspector for SEPTA shall have the right to reject the cable that is defective in any respect. B. Determination of Tests: Tests may be made at place of production or on samples submitted, or at destination as specified by SEPTA. The manufacturer shall notify the Director of Purchasing & Stores when they will have materials ready for inspection. Prior notification of desire to witness particular tests on specific cables shall be furnished by the manufacturer. C. Types of Tests: The manufacturer shall provide, at the point of production, apparatus and labor for making any or all of the following tests under the supervision of SEPTA's Inspector. Such tests include: 1. Conductor size and physical characteristics. 2. Insulation HV and IR Tests. 3. Physical Dimension Tests. 4. Special tests on materials in coverings. 5. Final HV, IR, and Conductor Resistance Tests on shipping reels

13 D. Certified Test Reports: The manufacturer shall furnish the Purchaser with six (6) certified copies of the results of all tests and measurements made to determine the quality and serviceability of the cable manufactured in accordance with this Specification. Such results shall show compliance with all the requirements of this Specification. Final approval shall be contingent upon receipt and approval by SEPTA of these certified tests. E. Rejected Cable: Cable that does not meet the requirements of this Specification and order shall be rejected. Wire or cable that shows defects or non-compliance with the Specification and order, after arrival at destination, may be rejected and the Seller shall, on request, advise disposition of the wire or cable in question and pay all transportation charges on the rejected material QUALITY ASSURANCE APPROVAL SEPTA reserves the right to judge the adequacy of the manufacturer's Quality Assurance Program and organization in relation to the degree of reliability expected of the cable. This judgement is to be made on the basis of plant visitations by SEPTA's Management and/or Engineering personnel SPLICING The insulation together with materials supplied for splicing the cables shall be such as to make dependable moisture-proof splices able to withstand the underground or aerial environment comparable to the unspliced cable. Instructions for such splices shall be furnished by the manufacturer

14 1.15 SHIPPING A. Minimum Shipping Lengths: Cable shall be furnished in lengths of approximately 1000 ft., unless otherwise specified. All cable shall be shipped on reels, adequately protected from damage in shipment by heavy wrapping or wood lagging. B. Reel Design: Reels shall be substantial to withstand reasonable handling and shall be so designed that the inner end of the cable will be accessible, but protected from injury. They shall be designated and constructed as non-returnable when drum size and cable weight and volume permit. C. Cable Winding on Reels: Cable shall be closely and tightly wound in each layer on reels and both ends shall be sealed to prevent the entrance of moisture and securely fastened so that they will not become loose in transit REEL MARKING A. Each reel shall contain on the outside flange plainly legible and weather resistant, information to show the manufacturer's name, purchaser's requisition number, lengths of each section of cable, number of conductors, gauge of conductors, and the name and address of the consignee

15 B. Reel Rolling Instructions: An arrow shall be painted on one head of each reel pointing the opposite direction from the outer end of the cable with the words "Roll This Way" WARRANTY A. The Seller shall expressly warrant that the insulated wire and cable furnished under this Specification shall be free from defects in material and workmanship. The Seller shall be responsible for the cable for the life of the installation, except that obligation under this warranty shall not apply to any wire or cable which has been subject to misuse, negligence, or accident after it has been accepted and shipped. B. The Seller shall covenant and agree to indemnify Southeastern Pennsylvania Transportation Authority against all claims, suits, actions, or proceedings, damages, costs, fees, and expenses by reason of infringement or alleged infringement of patents, or for patent royalties involved in consequence of the purchase and the use of the material covered hereby

16 APPENDIX "A" VITAL CIRCUIT SYNTHETIC RUBBER INSULATION PHYSICAL AND ELECTRICAL CHARACTERISTICS When tested with methods described in ASTM D and the procedures specified herein, the insulation shall have the following characteristics in comparison with AAR Signal Manual, Part 249, Specification and as evidence of a forty year design life. INSULATION 1. Physical properties: Original properties: Tensile strength - minimum psi Tensile 200% elongation min. psi Elongation at rupture - minimum % Properties after accelerated aging: Oxygen pressure test hours - 80 C (176 F) psi Tensile strength, minimum % of original Elongation, minimum % of original Air pressure heat test - 20 hours C (260 F) - 80 psi Tensile strength, minimum % of original Elongation, minimum % of original AAR SPEC GUARANTEED VALUES Insulation resistance constant: Megohms ft. at 15.6 C (60 F) min. 10,000 25, Mechanical water absorption: 7 days 70 C (158 F) - mg./sq.in. max Electrical stability in water on insulated conductors only: 1000 cycles 50 C (122 F). Dielectric constant One Day immersion maximum Increase in dielectric constant: 1-14 days - % maximum 7-14 days - % maximum Power Factor: 14 days - % maximum

17 APPENDIX "A" (cont'd) INSULATION 5. Accelerated electrical stability test in water on insulated conductors only: 80 volts/mil measurement stress 60 cycles - 90 C (194 F) Dielectric constant 1 day immersion maximum Increase in dielectric constant: 1-14 days - % maximum 7-14 days - % maximum 1-90 days - % maximum (1) 6. Power Factor 14 days - maximum % 90 days - maximum % (1) 7. Accelerated insulation resistance stability test on insulated conductors only at 90 C (194 F) megohms ft. 1 day immersion minimum 90 days immersion - minimum (1) AAR SPEC GUARANTEED VALUES Accelerated voltage stability test (1) A single conductor No. 14 AWG or larger size with 80 mils or thicker insulation wall, shall have at least 10 feet immersed in water at room temperature. The insulated conductor, without any coverings over the insulation, shall be continuously energized as follows: AC Voltage V/Mil Time Months or or or (1) No insulation failure shall occur within the test period

WESTERN UNDERGROUND COMMITTEE GUIDE 2.14 (2.14/01/0990)

WESTERN UNDERGROUND COMMITTEE GUIDE 2.14 (2.14/01/0990) ABRASION RESISTANT 600V CABLE NOTE: This "Guide" summarizes the opinions, recommendations, and practices of the Western Underground Committee members