1、 AMSC N/A FSC 6145 INCH-POUND MIL-DTL-28781E 22 August 2011 SUPERSEDING MIL-DTL-28781D 25 August 2006 DETAIL SPECIFICATION CABLE, ELECTRICAL, SPECIAL PURPOSE SHORE USE This specification is approved for use by all Departments and Agencies of the Department of Defense. 1. SCOPE 1.1 Scope. This specif
2、ication describes twisted-pair, multiconductor, shielded cables for use within shore communication stations and facilities. 1.2 Classification. Cables will be of the following number of pairs, as specified in the solicitation or contract (see 6.2): 1 pair 3 pairs 6 pairs 16 pairs 26 pairs 52 pairs 1
3、04 pairs 2. APPLICABLE DOCUMENTS 2.1 General. The documents listed in this section are specified in sections 3, 4, or 5 of this specification. This section does not include documents cited in other sections of this specification or recommended for additional information or as examples. While every e
4、ffort has been made to ensure the completeness of this list, document users are cautioned that they must meet all specified requirements of documents cited in sections 3, 4, or 5 of this specification, whether or not they are listed. Comments, suggestions, or questions on this document should be add
5、ressed to DLA Land and Maritime, ATTN: VAI, P.O. Box 3990, Columbus, Ohio 43218-3990, or email to WireCabledla.mil. Since contact information can change, you may want to verify the currency of this address information using the ASSIST Online database at https:/assist.daps.dla.mil. Provided by IHSNot
6、 for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-28781E 2 2.2 Government documents. 2.2.1 Specifications, standards, and handbooks. The following specifications, standards and handbooks form a part of this document to the extent specified herein. Unless otherwi
7、se specified, the issues of these documents are those cited in the solicitation or contract. FEDERAL STANDARD FED-STD-228 Cable and Wire, Insulated; Methods of Testing. DEPARTMENT OF DEFENSE SPECIFICATIONS MIL-DTL-16878 Wire, Electrical, Insulated, General Specification for. MIL-DTL-16878/1 Wire, El
8、ectrical, Polyvinyl Chloride (PVC) Insulated, 105 C, 600 Volts (Not for Navy Shipboard Use). (Copies of these documents are available online at https:/assist.daps.dla.mil/quicksearch/ or from the Standardization Document Order Desk, 700 Robbins Avenue, Building 4D, Philadelphia, PA 19111-5094.) 2.3
9、Non-Government publications. The following documents form a part of this document to the extent specified herein. Unless otherwise specified, the issues of these documents are those cited in the in the solicitation or contract. ASTM INTERNATIONAL ASTM-B33 Wire, Tinned Soft or Annealed Copper, For El
10、ectrical Purposes. ASTM-D470 Wire and Cable, Crosslinked Insulations and Jackets for. ASTM-D2240 Rubber Property-Durometer Hardness. (Copies of these documents are available online at http:/www.astm.org or from the ASTM International, P.O. Box C700, 100 Barr Harbor Drive, West Conshohocken, PA 19428
11、-2959.) NATIONAL ELECTRICAL MANUFACTURERS ASSOCIATION (NEMA) NEMA WC 70 Nonshielded Power Cables Rated 2000 Volts or Less for the Distribution of Electrical Energy. (Copies of these documents are available online at http:/www.nema.org or from the National Electrical Manufacturers Association, 1300 N
12、orth 17thStreet, Suite 1752, Rosslyn VA 22209.) X-RITE, INCORPORATED Munsell Color Charts for Plastic Cable and Wire. (Copies of these documents are available online at or from X-Rite Corporate Headquarters USA, 4300 44thSt. SE, Grand Rapids, MI 49512). Provided by IHSNot for ResaleNo reproduction
13、or networking permitted without license from IHS-,-,-MIL-DTL-28781E 3 2.4 Order of precedence. Unless otherwise noted herein or in the contract, in the event of a conflict between the text of this document and the references cited herein (except for related specification sheets), the text of this do
14、cument takes precedence. Nothing in this document, however, supersedes applicable laws and regulations unless a specific exemption has been obtained. 3. REQUIREMENTS 3.1. First article. When specified (see 6.2 and 6.3), a sample shall be subjected to first article inspection in accordance with 4.2.
15、3.2 Materials. 3.2.1 Conductors. The conductors shall utilize number 24 American Wire Gauge (AWG) (nominal diameter .0201 inch (.511 mm), tinned solid copper wire, in accordance with ASTM-B33. 3.2.1.1 Joining conductors. Joints made in conductors may be brazed using a silver alloy solder and a non-a
16、cid flux, or welded. Joints shall be butted and shall be free from lumps and sharp projections. The tensile strength of any section of a conductor joint that was brazed or welded shall be not less than 85 percent of the tensile strength of an adjacent section without a joint. 3.2.1.2 Conductor resis
17、tance. The direct current (dc) resistance of each conductor shall not exceed 30 ohms per 1,000-foot (304.8-meter) length, when measured at, or corrected for, 68 F. 3.2.2 Insulation material. The insulation material shall be .010.002-inch (.254.051 mm) thick polyvinyl chloride, in accordance with MIL
18、-DTL-16878 and MIL-DTL-16878/1, M16878/1BEA. A jacket of polyamide material .002.001 inch (.508.025 mm) thick shall be placed over the insulation. The outside diameter of the conductor, including insulation and polyamide material, is to be not greater than .0502 inch (1.275 mm) to permit application
19、 of commercially available cable connector devices. 3.2.2.1 Insulation defects. The insulation shall be smooth and free from holes, splits, blisters, and other imperfections. 3.2.2.2 Cold bend. The finished conductor insulation shall show no evidence of cracking or fracturing when cold bend tested i
20、n accordance with 4.6.4. 3.2.2.3 Color coding of insulation. The color coding shall be as shown in table I to identify each pair in the completed cable. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-28781E 4 TABLE I. Color coding. Pair numb
21、er Color Pair number Color 1 Blue and white (or natural) 27 Orange-white (stripe) and white (or natural) 2 Orange and white (or natural) 28 Green-white (stripe) and white (or natural) 3 Green and white (or natural) 29 Brown-white (stripe) and white (or natural) 4 Brown and white (or natural) 30 Slat
22、e-white (stripe) and white (or natural) 5 Slate and white (or natural) 31 Blue-white (stripe) and red 6 Blue and red 32 Orange-white (stripe) and red 7 Orange and red 33 Green-white (stripe) and red 8 Green and red 34 Brown-white (stripe) and red 9 Brown and red 35 Slate-white (stripe) and red 10 Sl
23、ate and red 36 Blue-white (stripe) and black 11 Blue and black 37 Orange-white (stripe) and black 12 Orange and black 38 Green-white (stripe) and black 13 Green and black 39 Brown-white (stripe) and black 14 Brown and black 40 Slate-white (stripe) and black 15 Slate and black 41 Blue-white (stripe)
24、and yellow 16 Blue and yellow 42 Orange-white (stripe) and yellow 17 Orange and yellow 43 Green-white (stripe) and yellow 18 Green and yellow 44 Brown-white (stripe) and yellow 19 Brown and yellow 45 Slate-white (stripe) and yellow 20 Slate and yellow 46 1/Blue-white (stripe) and violet 21 Blue and
25、violet 47 Orange-white (stripe) and violet 22 Orange and violet 48 Green-white (stripe) and violet 23 Green and violet 49 Brown-white (stripe) and violet 24 Brown and violet 50 Slate-white (stripe) and violet 25 Slate and violet 51 Red and white (or natural) 26 Blue-white (stripe) and White (or natu
26、ral) Spare 1/(For 52 or 104 pair) Red and Black 1/ At the manufacturers option, pair number 46 and the spare pair may be used to assure the required number of (non-defective) pairs. 3.2.2.3.1 Color standards. The colored insulation shall match the centroid colors of table II, within the limits of st
27、andards for colors as specified in Munsell Color Charts for Plastic Cable and Wire. The color pigments shall be chosen to yield uniform dielectric constant between colors and shall have no deteriorating effects on the insulation. Provided by IHSNot for ResaleNo reproduction or networking permitted w
28、ithout license from IHS-,-,-MIL-DTL-28781E 5 TABLE II. Munsell centroid colors. Tolerance limits Hue Value Chroma Color Centroid H- H+ V- V+ C- C+ Red 2.5R 4/12 1.25R 4/12 3.75R 4/12 2.5R 3/12 2.5R 4.5/12 2.5R 4/10 None Orange 2.5YR 6/14 1.25R 6/14 3.75YR 6/14 2.5YR 5/14 2.5YR 6.5/14 2.5YR 6/12 None
29、 Brown 2.5YR 3.5/6 10R 3.5/6 5YR 3.5/6 2.5YR 3/6 2.5YR 4/6 2.5YR 3.5/4 2.5YR 3.5/7 Yellow 5Y 8.5/12 2.5Y 8.5/12 7.5Y 8.5/12 5Y 8/12 None 5Y 8.5/10 None Green 2.5G 5/12 1.25 G5/12 3.75G 5/12 2.5G 4/10 2.5G 5.5/12 2.5G 5/9 None Blue 2.5PB 4/10 10B 4/10 5PB 4/10 2.5PB 3.5/10 2.5PB 4.5/10 2.5PB 4/9 None
30、 Violet 2.5P 4/10 1.25P 4/10 3.75P 4/10 2.5P 3/10 2.5P 4.5/10 2.5 4/8 None Neutral colors White N 9/ Value tolerances: V- is N 8.75; no V+ limit. Chromaticity tolerances: 5R 9/1 5G 9/.5 5YR 9/1 5B 9/.5 5Y 9/1 5P 9/.5 Slate N 5/ Value tolerances: V- is N 4.5/; V+ is N 5.5/ Chromaticity tolerances: 5R
31、 5/.5 5B 5/.5 5Y 5/.5 5P 5/.5 5G 5/.5 Black N 2/ Value tolerances: No V- limit; V+ is N 2.3 Chromaticity tolerances: 5R 2/.5 5B 2/.5 5Y 2/.5 5P 2/.5 5G 2/.5 3.2.2.3.2 Insulation stripes. Striping shall be such as to provide readily discernible stripes on the conductor insulation. These stripes may b
32、e integral of the insulation or the striping may be provided as an internal plastic coating. Striping shall firmly adhere to the insulation and remain intact through the life of the conductor insulation. Insulation striping in accordance with method 1 of NEMA WC 70 is acceptable. 3.2.2.4 Twisting of
33、 pairs. The insulated conductors shall be twisted into pairs. The average length of pair twists in any pair in the finished cable, when measured on any 10-foot (3.05 m) length, shall not exceed 6 inches (152.4 mm). 3.2.2.4.1 Crosstalk loss. The root mean square (rms) output-to-output far-end crossta
34、lk loss, as measured on the completed cable at a test frequency of 150-kilohertz (kHz), shall not be less than 70 dB per 1,000 feet (304.8 m). 3.2.2.5 Heat resistance. The insulation shall exhibit no cracking or delamination and no readily visible defects in any of the wire components after being su
35、bjected to the heat conditions of MIL-DTL-16878/1. 3.2.2.6 Shrinkage. When subjected to contact with molten solder, the insulation shall not flare away from the conductor, open up over the bent portion called for in the test, nor shrink back more than .125 inch. (3.18 mm) Provided by IHSNot for Resa
36、leNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-28781E 6 3.2.3 Cable forming. The twisted pairs shall be assembled to form a substantially cylindrical core. Adjacent layers may be stranded in the same direction or in opposite directions. For a 104-pair cable, the cable
37、 shall be formed in two 52-pair concentric units or four 26-pair units. 3.2.3.1 Binder. A colored binder shall be applied around the units for separation. The colors shall be readily recognizable. Bindings shall be applied with a lay of not more than 4 inches. The binder may be either a non-hygrosco
38、pic thread or tape. 3.2.3.2 Binder colors. The colors for each unit binder shall be as follows: Unit Color of binding 1 Blue-White 2 Orange-White 3 Green-White 4 Brown-White 5 Slate-White 3.2.4 Core covering. The core covering shall be completely covered with Mylar (Mylar is a registered trademark o
39、f E.I. Dupont Co.), polyethylene, or Mylar backed SBR (Styrene-Butadiene Rubber) or equivalent, which shall be non-hygroscopic and shall be applied with an overlap. The core covering shall provide a sufficient heat barrier to prevent visible evidence of conductor insulation deformation or adhesion b
40、etween conductors caused by adverse heat transfer during the jacketing operation. 3.2.4.1 Dielectric strength. In each length of completed cable, the insulation between conductors, and between conductors and shield, shall withstand the dielectric dc potential for 3 seconds as follows: dc volts Betwe
41、en conductors 3,600 Between conductors and shield 1,800 3.2.5 Shield. An overall tinned copper braid shield shall be applied over the core-covering. The shield shall cover 90 percent of the cable core. 3.2.5.1 Shield resistance. The dc resistance of the shield for a 1000-foot (304.8-meter) length of
42、 completed cable shall not exceed the values shown below: No. of pairs dc resistance 1 5.75 ohms 3 4.00 ohms 6 3.50 ohms 26 2.10 ohms 3.2.6 Jacket material. The jacket material shall be black colored polyvinyl chloride containing a minimum of 1 percent of carbon black, or similar material, to resist
43、 ultraviolet light. The jacket material shall conform to the physical (finished cable) requirements outlined in 3.2.6.1 through 3.2.6.4. The cable jacket shall have a type A durometer hardness of 805. 3.2.6.1 Tensile strength. The cable jacket shall have a minimum tensile strength of 2000 pounds per
44、 square inch (psi). 3.2.6.2 Elongation. The cable jacket shall have a minimum elongation of 250 percent. Provided by IHSNot for ResaleNo reproduction or networking permitted without license from IHS-,-,-MIL-DTL-28781E 7 3.2.6.3 Jacket thickness and outside cable diameter. The jacket thickness and ou
45、tside cable diameter shall be as specified in table III. The minimum spot thickness of the jacket shall not be less than 70 percent of the specified thickness. The average thickness at any cross-section of the jacket material shall be not less than 90 percent of the specified thickness. TABLE III. J
46、acket thickness and outside diameter (OD). No. of pairs Nominal jacket thickness Approx. OD inches millimeters inches millimeters 1 .050 1.270 .227 5.765 3 .050 1.270 .315 8.001 6 .050 1.270 .388 9.855 16 .062 1.5748 .506 12.852 26 .062 1.5748 .615 15.621 52 .062 1.5748 .781 19.837 104 .070 1.778 1.
47、137 28.900 3.2.6.4 Cold bend for jacket material. A sample of the finished cable shall show no evidence of cracking or fracturing. 3.2.7 Cable marking. A tape shall be permanently marked and inserted between the jacket and shield. The length shall be marked every 12 inches (304.8 mm). The tape shall
48、 be marked at least every 24 inches (609.6 mm) with the following: a. Manufacturers name (or symbol designation). b. Date of manufacture. c. Contract number. d. Specification number. 3.3 Electrical requirements. 3.3.1 Mutual capacitance. The average mutual capacitance of all pairs in a completed reel of cable of three or more pairs shall not exceed .152 microfarad (F) per 1 mile (1.609 kilometers). The average mutual capacitance of all pairs also shall not exceed .160 F per 1 mile f
