SPECIFICATION: 1200 THIS ISSUE: DATE: Issue 10 5 November 2001 Wire and Cable REPLACES: Issue 9 501 Oakside Avenue, Redwood City, CA 94063-3800 PAGE: 1 of 38 CABLE, HIGH-FREQUENCY AND CONTROLLED ELECTRICAL 1. SCOPE This specification covers inspection methods, procedures and requirements for highfrequency and controlled electrical cables. 2. APPLICABLE DOCUMENTS 2.1 GOVERNMENT-FURNISHED DOCUMENTS The following documents, of the issue in effect on the date of invitation for bids or request for proposal, form a part of this specification to the extent specified herein. 2.1.1 Military SPECIFICATIONS MIL-C-17 MIL-C-915 MIL-W-22759 MIL-W-29606 MIL-C-85485 Cables, Radio Frequency, Flexible and Semirigid, General Specification for Cable and Cord, Electrical, for Shipboard Use, General Specification for Wire, Electric, Fluoropolymer-Insulated, Copper or Copper Alloy Wire, Electrical, Stranded, Uninsulated Copper, Copper Alloy, or Aluminum, or Thermocouple Extension, General Specification for Cable, Electric, Filter Line, Radio Frequency, Absorptive STANDARDS MIL-STD-202 2.1.2 Test Methods for Electronic and Electrical Component Parts Federal SPECIFICATIONS UU-T-450 Tissue, Facial (Copies of government-furnished documents may be obtained from the Defense Automation and Production Service, 700 Robbins Avenue, Bldg. 4/D, Philadelphia, Pennsylvania 19111-5094; or at http://astimage.daps.dla.mil/quicksearch.) NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. Page 2 SPECIFICATION 1200, ISSUE 10 2.2 OTHER PUBLICATIONS The following documents form a part of this specification to the extent specified herein. Unless otherwise indicated, the issue in effect on date of invitation for bid or request for proposal shall apply. 2.2.1 American National Standard (ANSI) ANSI/ASQC Z1.4 Sampling Procedures and Tables for Inspection by Attributes (Copies of ASQC documents may be obtained from the American Society for Quality Control, 611 E. Wisconsin Avenue, Milwaukee, Wisconsin 53202; or at www.asqc.org.) 2.2.2 American Society for Testing and Materials (ASTM) B 193 D 3032 D 4566 Standard Test Method for Resistivity of Electrical Conductor Materials Standard Methods of Testing Hookup Wire Insulation Standard Test Methods for Electrical Performance Properties of Insulations and Jackets for Telecommunications Wire and Cable Standard Test Method for Total Loss and Collected Volatile Condensable Materials from Outgassing in a Vacuum Environment E 595 (Copies of ASTM documents may be obtained from the American Society for Testing and Materials, 1916 Race Street, Philadelphia, Pennsylvania 19103; or at www.astm.org.) 2.2.3 Canadian Standards Association (CSA) C22.2 No. 0.3 Test Methods for Electrical Wires and Cables (Copies of CSA documents may be obtained from CSA International, 178 Rexdale Boulevard, Toronto, Ontario, Canada M9W 1R3; or at www.csa-international.org.) 2.2.4 Department of Transportation, Federal Aviation Administration FEDERAL AVIATION REGULATIONS (FAR) Part 25 Airworthiness Standards: Transportation Category Airplanes (Copies of Department of Transportation, Federal Aviation Administration documents may be obtained from the Superintendent of Documents, Government Printing Office, Washington, D.C. 20402; or at www.faa.gov.) 2.2.5 International Organization for Standardization (ISO) 8402 Quality Management and Quality Assurance - Vocabulary (Copies of ISO documents may be obtained from the International Organization for Standardization, or at www.iso.ch.) NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. SPECIFICATION 1200, ISSUE 10 2.2.6 Page 3 National Electrical Manufacturers Association (NEMA) WC27500 Standard for Aerospace and Industrial Electrical Cable (Copies of NEMA documents may be obtained from NEMA, 1300 North 17th Street, Rosslyn, VA; or at www.nema.org.) 2.2.7 Society of Automotive Engineers, Inc. (SAE) J1128 Low Tension Primary Cable (Copies of SAE documents may be obtained from SAE, 400 Commonwealth Drive, Warrendale, PA 15096-0001, or at www.sae.org.) 2.2.8 Underwriters Laboratories (UL) UL 1581 Reference Standard for Electrical Wires, Cables, and Flexible Cords (Copies of UL documents may be obtained from Underwriters Laboratories Inc., Publications Stock, 333 Pfingsten Road, Northbrook, Illinois 60062-2096; or at www.ul.com.) 3. REQUIREMENTS 3.1 SPECIFICATION SHEETS The requirements for the cables furnished under this specification shall be as specified herein and in accordance with the applicable specification sheet. The requirements of the specification sheet shall govern. 3.2 MATERIALS 3.2.1 Conductor Materials Conductor materials shall be in accordance with MIL-W-29606 and the applicable specification sheet. 3.2.2 Shield Materials Shield materials shall conform to the requirements of NEMA WC27500 and the applicable specification sheet. 3.2.3 Insulating and Jacket Materials Insulating and jacketing materials shall be in accordance with the applicable specification sheet. 3.3 PROCESS-CONTROL 3.3.1 Conductor Splices Splices shall be in accordance with MIL-W-29606. NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. Page 4 SPECIFICATION 1200, ISSUE 10 3.4 CONSTRUCTION Construction of the finished cable shall be as specified herein and on the applicable specification sheet. 3.4.1 Conductor Unless otherwise specified on the applicable specification sheet, the conductor construction shall be in accordance with MIL-W-29606. 3.4.1.1 Conductor Elongation and Breaking Strength Prior to dielectric extrusion, tensile strength and elongation of the conductor shall be in accordance with MIL-W-29606 as applicable. Other materials not covered by MIL-W29606 shall be in accordance with the applicable specification sheet. 3.4.2 Shield The shield shall be constructed so as to meet all physical and surface transfer impedance requirements of the applicable specification sheet. The shield shall be free of irregularities, discontinuities and whole braid splices. 3.4.3 Insulation and Jackets All insulating and jacket materials shall be constructed as specified in the applicable specification sheet. 3.5 DETAIL REQUIREMENTS Finished cable shall conform to the requirements of Table I and those of the specification sheet, as applicable. 3.5.1 Conductor and Shield Continuity One hundred percent of all finished cable shall be tested for continuity prior to shipment. There shall be no discontinuity in any of the component wires or shields, as applicable. 3.5.2 Dielectric Concentricity Where required, the dielectric concentricity shall be in accordance with the applicable specification sheet when tested in accordance with 4.4.9. 3.5.3 Dielectric Flaws When specified, one hundred percent of the dielectric insulation shall be tested after application of the dielectric and prior to the application of any other material to the wire. Testing shall be in accordance with the jacket flaws test of 4.4.18 and best manufacturing practice. 3.5.4 Flammability Finished cable shall be tested in accordance with 4.4.14 for the appropriate method as specified on the applicable specification sheet. Unless otherwise specified on the applicable specification sheet, finished cable shall meet the following requirements: NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. SPECIFICATION 1200, ISSUE 10 3.5.4.1 Page 5 Method A, Vertical Test, Inclined Burner 60 seconds (maximum) 25 percent (maximum) of flag burned No flaming of cotton 3.5.4.2 Method B, 60 Test, Inclined Burner 30 seconds (maximum) 3 inches (76 mm) (maximum) No flaming of facial tissue 3.5.4.3 Method C, Horizontal Test, Vertical Burner No flaming of indicator papers. 3.5.4.4 Method D, 45 Test, Inclined Burner 70 seconds maximum 3.5.5 Jacket Concentricity and Wall Thickness Unless otherwise specified in the applicable specification sheet, the jacket concentricity shall be 70 percent, minimum, when tested with 4.4.17. The jacket wall thickness shall be as specified in the applicable specification sheet. 3.5.6 Jacket Flaws One hundred percent of the finished cable shall pass the impulse test or spark test of 4.4.18, using the voltage specified in the applicable specification sheet. Jacket flaws testing shall be performed during the final winding on shipment spools or reels. 3.5.7 Low Temperature Cold Bend When finished cable is tested in accordance with 4.4.19, there shall be no cracking and no breakdown. 3.5.8 Workmanship All details of workmanship shall be in accordance with high-grade wire and cable manufacturing practice. The insulation shall be free of cracks, splits, irregularities and imbedded foreign material. 4. QUALITY ASSURANCE PROVISIONS 4.1 RESPONSIBILITY FOR INSPECTION The supplier is responsible for the performance of all tests specified herein. The supplier may utilize internal or any other inspection facility and services acceptable to the buyer. Inspection records of the examinations and tests shall be kept complete and available to the buyer as required. NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. Page 6 SPECIFICATION 1200, ISSUE 10 4.2 QUALITY-CONFORMANCE INSPECTION Quality-conformance inspection shall consist of all applicable examinations and tests listed in Table 1. Quality-conformance inspection shall be performed on every lot of cable procured under this specification. 4.2.1 Inspection Classifications a. Vendor Control (V) - Requirements for raw materials such as conductor and insulation materials over which the vendor has control and responsibility. b. Process Control (P) - Inspections performed on samples taken from the lots of cable. Inspections may be performed on finished cable or after the process which establishes the specified characteristic. The Quality Control Plan establishes the frequency of inspection based on process control data. c. One hundred Percent (100%) - Test performed on the total length of each cable. Tests may be performed on the finished product or "in process" as applicable. 4.2.2 Inspection Definitions ISO 8402 shall apply for definitions of inspection terms used herein. For the purposes of this specification, the following shall apply: 4.2.2.1 Lot The inspection lot shall include all cable(s) of one part number subjected to inspection at one time. 4.2.3 Nonconforming Inspection Lots Disposition of inspection lots found unacceptable under initial quality-conformance inspection shall be in accordance with ANSI/ASQC Z1.4. 4.3 INSPECTION CONDITIONS Unless otherwise specified herein, all test inspection conditions shall be in accordance with the test conditions specified in the "General Requirements" of MIL-STD-202, as follows: a. Temperature: 25C 10C b. Relative humidity: 60 percent 15 percent c. Atmospheric pressure: 725 mm 75 mm of mercury 4.4 TEST METHODS NOTE: Where more than one test method is given for determining a particular property required by the applicable specification sheet, Method A shall be used unless otherwise specified by the applicable specification sheet. NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. SPECIFICATION 1200, ISSUE 10 Page 7 TABLE 1 PROPERTIES OF FINISHED CABLE Examination or Test Requirement Method Inspection Class Adhesion of Conductor Attenuation Blocking Cabling Capacitance Capacitance Unbalance Characteristic Impedance Conductor Elongation and Breaking Strength Conductor and Shield Continuity Conductor and Shield Resistance Conductor Splices Construction and Materials Dielectric Concentricity Dielectric Flaws Dielectric/Jacket Elongation and Tensile Strength Dimensional Stability Dimensions Flammability Heat Shock Insulation Resistance Jacket Concentricity and Wall Thickness Jacket Flaws Low Temperature Cold Bend Outer Space Environmental Testing Partial Discharge (Corona) Propagation Delay Shield Coverage Skew Structural Return Loss Surface Transfer Impedance Time Delay Velocity of Propagation Voltage Withstand (Dielectric) Voltage Withstand (Post-Environmental) Weight Workmanship Specification Sheet Specification Sheet Specification Sheet Specification Sheet Specification Sheet Specification Sheet Specification Sheet 3.4.1.1 3.5.1 Specification Sheet 3.3.1 Specification Sheet, 3.2 and 3.4 3.5.2 Specification Sheet and 3.5.3 Specification Sheet Specification Sheet Specification Sheet Specification Sheet and 3.5.4 Specification Sheet Specification Sheet 3.5.5 3.5.6 Specification Sheet and 3.5.7 Specification Sheet Specification Sheet Specification Sheet Specification Sheet Specification Sheet Specification Sheet Specification Sheet Specification Sheet Specification Sheet Specification Sheet Specification Sheet Specification Sheet 3.5.8 4.4.1 4.4.2 4.4.3 4.4.13 4.4.4 4.4.5 4.4.6 MIL-W-29606 4.4.7 4.4.8 4.4.13 4.4.13 4.4.9 4.4.18 4.4.10 4.4.11 4.4.12 4.4.14 4.4.15 4.4.16 4.4.17 4.4.18 4.4.19 4.4.20 4.4.21 4.4.22 4.4.23 4.4.24 4.4.25 4.4.26 4.4.27 4.4.28 4.4.29.1 4.4.29.2 4.4.30 4.4.13 P P P P P P P V 100% P V P P 100% P P P P P P P 100% P 1/ P P P P P P P P 100% P P P 1/ Outer Space testing shall be performed at a frequency that has been agreed upon between the customer and Raychem. NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. Page 8 SPECIFICATION 1200, ISSUE 10 4.4.1 Adhesion of Conductor 4.4.1.1 Specimen Preparation Two specimens shall be cut to the length shown in Figure 1 using shear-type cutters to minimize cross-sectional distortion. The jacket and shield shall be cut and carefully removed without bending or flexing the cable. The dielectric shall be removed using a razor blade without disturbing the remaining dielectric. Dielectric Conductor 3.0 0.25 inch 3.0 0.25 inch (76 6.4mm) (76 6.4mm) Figure 1. Conductor Adhesion Dimension 4.4.1.2 Apparatus A test fixture capable of being held in a tensile testing machine and providing a hole for the conductor to pass through shall be used. Clearance holes for conductors shall be no smaller than the diameter of the conductor plus 0.002 inch (0.5 mm) and no larger than the smallest practicable numerical drill size. 4.4.1.3 Procedure With the conductor passing through the appropriate hole, the conductor shall be clamped in one set of jaws while the test fixture is held or supported by the other set of jaws. The jaws shall be separated at a rate of 0.5 inch (13 mm) per minute and the force recorded while the conductor is pulled out of the dielectric. The maximum force recorded shall be designated as the strip force and shall meet the requirements of the applicable specification sheet. 4.4.1.4 Test Method Derivation The preceding test method is derived from the Adhesion of Conductor test method in MIL-C-17. NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. SPECIFICATION 1200, ISSUE 10 Page 9 4.4.2 Attenuation 4.4.2.1 Specimen The specimen shall be of sufficient length to exhibit at least 3 dB of attenuation at the lowest frequency required. The specimen shall be short enough to ensure that the measured signal is at least 10 dB higher than the measuring system noise floor. If the frequency range is such that one specimen cannot fulfill this requirement, then an additional specimen of suitable length shall be used. For coaxial-type cables, suitable connectors shall be attached to both ends of the cable. For twisted pairs, a connector board with insulation displacement connectors may be used. 4.4.2.2 Procedure An appropriate test set shall be used to measure the attenuation of the sample. Calibration and specimen measurements shall be made in accordance with the analyzer or system procedures. The attenuation at any frequency shall be expressed by the formula: Attenuation in dB / 100 feet (or dB / 100 m) = 4.4.2.3 Measured Attenuation ( dB) x100 Specimen length in feet (meters) Determination of Compliance Within the frequency range(s) specified on the applicable specification sheet, the attenuation shall not exceed the specified value. Due to reflections, it may be necessary to perform an standard regression analysis on the raw data. The regression polynomial used shall be: A( f ) = a1 f + a 2 f Where: f = Frequency in MHz a1, a2 = Coefficients determined by regression analysis A(f) = Attenuation in dB/100 feet (or dB/100 m) at frequency (f) The regression analysis is used to smooth out SWR effects. To determine compliance, the frequency (or frequencies) listed on the specification sheet shall be substituted into the above equation, along with the regression coefficients a1 and a2, and the attenuation A(f) calculated. 4.4.2.4 Test Method Derivation The preceding test method is derived from the Attenuation test methods in MIL-C-17 and ASTM D4566. NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. Page 10 SPECIFICATION 1200, ISSUE 10 4.4.3 Blocking One end of a continuous length of finished cable shall be fixed to a mandrel specified in the applicable specification sheet. The cable shall then be spirally wound around the mandrel so at least three turns are in close contact with one another. The winding shall be continued until there are three layers of turns with each layer in close contact with one another. The mandrel and cable shall then be placed within an air oven for the time and at the temperature specified in the applicable specification sheet. After removal from the oven, the mandrel and cable shall be cooled to room temperature and the cable shall be unwound. There shall be no adhesion or sticking of adjacent turns or layers during the unwinding process. 4.4.3.1 Test Method Derivation The preceding test method is derived from the Blocking test method in NEMA WC27500. 4.4.4 Capacitance 4.4.4.1 Specimen Preparation For measuring a frequency of 1 MHz, the specimen shall consist of an approximate 10foot (3-m) length of finished cable with all shields removed for a distance of 1 inch (25 mm) from each end and the insulation removed for a distance of 0.5 inch (13 mm) from the end of all conductors. The length of the specimen shall be the shielded length. For measuring frequencies other than 1 MHz, the sample shall be prepared as above except that the specimen length shall be less than 1/40 wavelength. 4.4.4.2 Configuration For coaxial and triaxial cables only, capacitance shall be measured with a capacitance bridge at 1 kHz unless otherwise specified on the applicable specification sheet. For pair and triad cables, the frequency shall be 1 MHz unless otherwise specified. If the frequency specified for shielded or unshielded pairs or triads is 1 kHz, an appropriate capacitance bridge that performs measurements in accordance with ASTM D4566 may be used. 4.4.4.3 Procedure 4.4.4.3.1 Coaxial Cables The capacitance (C) shall be measured between the inner conductor and outer conductor (shield) with the outer shield grounded. NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. SPECIFICATION 1200, ISSUE 10 4.4.4.3.2 Page 11 Shielded Pair Cables The capacitance between the two inner conductors shall be measured by the two-terminal method. With the outer conductor (shield) connected to the ground terminal of the capacitance bridge, the mutual capacitance shall be determined as follows: Designate: Ca = Capacitance between no. 1 conductor and no. 2 conductor, with no. 2 conductor connected to the outer conductor. Cb = Capacitance between no. 2 conductor and no. 1 conductor, with no. 1 conductor connected to the outer conductor. Cc = Capacitance between no. 1 and no. 2 conductors connected together and the outer conductor. The mutual capacitance (Cm) per unit length for each shielded pair shall be determined by the formula: Cm = 4.4.4.3.3 2(Ca + Cb ) - Cc 4(Length of specimen) Shielded Triad Cables The capacitance shall be measured by the two-terminal method. With the outer conductor (shield) connected to the ground terminal of the capacitance bridge, the mutual capacitance shall be determined as follows: Designate: Ca = Capacitance between no. 1 conductor and all other conductors connected to the outer conductor. Cb = Capacitance between no. 2 conductor and all other conductors connected to the outer conductor. Cc = Capacitance between no. 3 and all other conductors connected together and the outer conductor. Cd = Capacitance between no. 1, no. 2 and no. 3 conductors connected together and the outer conductor. The mutual capacitance (Cm) per unit length for each shielded triad shall be determined by the formula: Cm = NOTE: 3(Ca + Cb + Cc ) - Cd 12(Length of specimen) ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. Page 12 SPECIFICATION 1200, ISSUE 10 4.4.4.3.4 Unshielded Pair Cables For unshielded pairs, the procedure shall be the same as given for shielded pair cables except that the overall shield, if any, and all the conductors of the specimen, except the pair under test, shall be connected together and treated as the outer conductor when making measurements. The mutual capacitance (Cm) for each pair shall be determined by the formula specified for the shielded pairs. 4.4.4.3.5 Unshielded Triad Cables For unshielded triad cables, the procedure shall be the same as given for shielded triads except that the overall shield, if any, and all conductors of the specimen, except those of the triad under test, shall be connected together and treated as the outer conductor when making measurements. The mutual capacitance (Cm) for each triad shall be determined by the formula specified for shielded triads. 4.4.4.4 Test Method Derivation The preceding test methods are derived from the Capacitance test methods in MIL-C-17, MIL-C-915 and ASTM D4566. 4.4.5 Capacitance Unbalance 4.4.5.1 Capacitance Unbalance to Shield 4.4.5.1.1 Capacitance Unbalance Pair-to-Shield The capacitance shall be determined in accordance with 4.4.4. The capacitance unbalance (Cu) in percent shall be determined from the following formula: Cu = 4.4.5.1.2 400 Ca - Cb 2( Ca + Cb ) - Cc % Capacitance Unbalance Triad-to-Shield The capacitance shall be determined in accordance with 4.4.4. The capacitance unbalance (Cu) in percent shall be determined from the following formula: Cu1 = Cu 2 = Cu 3 = NOTE: 200 Ca - Cb (Ca + Cb ) 200 Cb - Cc (Cb + Cc ) 200 Ca - Cc ( Ca + C c ) % % % ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. SPECIFICATION 1200, ISSUE 10 4.4.5.1.2 Page 13 Capacitance Unbalance Triad-to-Shield (cont'd) Where: Cu1 = Percent of capacitance unbalance of conductor no. 1 in relation to conductor no. 2. Cu2 = Percent of capacitance unbalance of conductor no. 2 in relation to conductor no. 3. Cu3 = Percent of capacitance unbalance of conductor no. 3 in relation to conductor no. 1. 4.4.5.1.3 Test Method Derivation The preceding test methods are derived from the Capacitance Unbalance test method in MIL-C-17, and the Capacitance test method in MIL-C-915. 4.4.5.2 Capacitance Unbalance Pair-to-Pair Capacitance unbalance between the pairs of a finished cable shall be measured using a suitable meter or bridge specifically designed for use with telephone cable. The cable sample shall be connected to the measuring instrument in accordance with the instrument manufacturer's procedure. The measurement frequency shall be 1 kHz. The capacitance unbalance of all adjacent and alternate pairs shall be measured as well as the capacitance unbalance between the pairs in adjacent layers. A lesser number of measurements may be made if allowed by the applicable specification sheet. The measured value of the capacitance unbalance for the particular sample under test shall be converted to an unbalance per 1000 feet (or km) by use of the following formula: Cu = CuL 1000 L Where: Cu = Capacitance unbalance in pF/1000 feet (or pF/km). CuL = Measured capacitance unbalance of sample in picofarads (pF). L = Length of sample in feet (or meters). 4.4.5.2.1 Test Method Derivation The preceding test method is derived from the Capacitance Unbalance Pair-to-Pair section of ASTM D4566. 4.4.5.3 Capacitance Unbalance Pair-to-Ground Capacitance unbalance between the pairs of finished cable and ground shall be measured using a suitable meter or bridge specifically designed for use with telephone cable. The cable sample shall be connected to the measuring instrument in accordance with the instrument manufacturer's procedure. The measurement frequency shall be 1 kHz. If a capacitance unbalance bridge is not available, the pair-to-ground capacitance unbalance shall be calculated using the following formula: ( ) ( Cupg = Cag + Cap - Cbg + Cbp NOTE: ) ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. Page 14 SPECIFICATION 1200, ISSUE 10 4.4.5.3 Capacitance Unbalance Pair-to-Ground (cont'd) Where: Cupg = Capacitance unbalance between pair and ground of sample in picofarads (pF). Cag = Capacitance between conductor `a' and ground. Cap = Capacitance between conductor `a' and all other pairs in the cable connected together and grounded. Cbg = Capacitance between conductor `b' and ground. Cbp = Capacitance between conductor `b' and all other pairs in the cable connected together and grounded. The measured value of the capacitance unbalance for the particular sample under test shall be converted to an unbalance per 1000 feet (or km) by use of the following formula: Y1 = 1000Y X Where: Y1 = Unbalance corrected to 1000 feet (or km) Y = Unbalance of cable length X = Cable length in feet (or meters) 4.4.5.3.1 Test Method Derivation The preceding test method is derived from the Capacitance Unbalance Pair-to-Ground section of ASTM D4566. 4.4.6 Characteristic Impedance 4.4.6.1 Characteristic Impedance - Method A This method shall be used for cables whose nominal impedance is within 20 percent of Zref, where Zref is the impedance of the calibrated air line (CRAL). However, if the Time Domain Reflectometer (TDR) has the capability of displaying ohms at cursor, this method may also be used for cables whose nominal impedance falls outside 20 percent of the impedance of the CRAL. 4.4.6.1.1 Specimen Preparation For coaxial cable, attach a suitable connector at one end of the cable. For twisted pairs, the measurement is made wire-to-wire. Designate one wire as the inner conductor and the other wire as the outer conductor and attach a suitable connector at one end. 4.4.6.1.2 Apparatus The apparatus shall consist of a TDR with a maximum rise time of 150 picoseconds. A calibrated reference air line (CRAL) of suitable impedance and suitable connectors shall be used. NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. SPECIFICATION 1200, ISSUE 10 4.4.6.1.3 Page 15 Procedure Attach the CRAL to the TDR output. If the TDR displays ohms at cursor, follow the instrument manufacturer's procedure. If not, designate the resulting trace as Zref and adjust horizontal magnifier control until Zref extends through at least six horizontal divisions. The sample cable shall then be attached and the resulting addition to Zref shall be designated as Zc. With the cable attached, the Reflection Coefficient dial shall be adjusted so that Zref and Zc are both on the graticule portion of the screen, but as far apart vertically as possible. Record the setting on the dial as ARC. Determine the vertical spacing between Zref and Zc in vertical divisions and designate as u. If Zref is higher than Zc, then u is negative. If Zref is lower than Zc, then u is positive. Define as: = u * ARC Characteristic impedance, Zo, shall be determined from the following formula: Zo = Zref 4.4.6.1.4 1+ 1- Test Method Derivation The preceding test method is derived from the Characteristic Impedance test method in MIL-C-17. 4.4.6.2 Characteristic Impedance - Method B This method shall be used for the determination of the characteristic impedance of coaxial cables only. 4.4.6.2.1 Procedure The velocity of propagation (Vp) shall be determined in accordance with 4.4.28. The capacitance (C) shall be determined in accordance with 4.4.4. The characteristic impedance shall be determined from the relation: Zo = 4.4.6.2.2 101670 V p (%) C( pF / ft ) Test Method Derivation The preceding test method is derived from the Characteristic Impedance test method in MIL-C-17. NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. Page 16 SPECIFICATION 1200, ISSUE 10 4.4.6.3 Characteristic Impedance - Method C This method is appropriate for determination of the characteristic impedance of cables at specified frequencies of 1 MHz or higher. 4.4.6.3.1 Procedure Using a 1 MHz bridge, determine the capacitance (C) in accordance with 4.4.4. The end of the specimen used to determine the capacitance shall then be shorted and the inductance (L) of the specimen determined using a 1 MHz bridge. Determination of the capacitance and inductance may also be made at other specified frequencies by use of a suitable bridge. For determining the characteristic impedance at frequencies higher than 1 MHz, the sample length should be shortened in order to minimize the effect of resonance. The characteristic impedance, at the specified frequency, shall be determined from the relation: Zo = L C Where: Zo is the characteristic impedance in ohms when L is the inductance in henries and C is the capacitance in farads For multiconductor cables, the capacitance (C) shall be the mutual capacitance (Cm). 4.4.6.3.2 Test Method Derivation The preceding test method is derived from the Characteristic Impedance test method in MIL-C-915. 4.4.6.4 Characteristic Impedance - Method D This method is appropriate for determination of the characteristic impedance of data bus (balanced pair) cables at specified frequencies of 772 kHz or higher. 4.4.6.4.1 Procedure Using an appropriate bridge or measurement system, the open circuit impedance (Zoc) and short circuit impedance (Zsc) shall be measured. For determining the characteristic impedance at frequencies higher than 1 MHz, the sample length should be shortened in order to minimize the effect of resonance. The characteristic impedance, at the specified frequency, shall be determined from the relation: Z o = Z oc Z sc Where: Zo = Complex characteristic impedance in ohms Zoc = Complex open circuit impedance in ohms Zsc = Complex short circuit impedance in ohms NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. SPECIFICATION 1200, ISSUE 10 4.4.6.4.1 Page 17 Procedure (cont'd) For electrically long lines (more than 1/8 of a wave length), the presence of structural variations influences the impedance observed at the measured end considerably, so that it is not actually Zo but rather an input impedance (Zin). For this situation, least squares function fitting techniques can be used to extract the characteristic impedance from the input impedance. 4.4.6.4.2 Test Method Derivation The preceding test method is derived from the Characteristic Impedance test method in ASTM D4566. 4.4.7 Conductor and Shield Continuity To establish continuity, 25 volts dc maximum shall be applied to both ends of each conductor and shield of the cable through an appropriate indicator, such as an ohmmeter, light, or buzzer. The test voltage may be applied to the conductors and shields individually or in series. 4.4.7.1 Test Method Derivation The preceding test method is derived from the Continuity test method in MIL-C-17. 4.4.8 Conductor and Shield Resistance Electrical resistance shall be determined on conductors or shields, as applicable, as specified on the applicable specification sheet. The test procedure shall be in accordance with ASTM B193. All test results shall be corrected to 20C, unless otherwise specified. 4.4.9 Dielectric Concentricity The concentricity of the dielectric insulation shall be determined by first locating and recording the minimum wall thickness measured on a cross-section of the dielectric insulation. The maximum wall thickness of this same cross-section of dielectric shall also be located and recorded. All wall thickness measurements shall be made under suitable magnification. The wall thickness shall be the shortest distance between the outer rim of the dielectric insulation and the outer rim of the underlying strand of the conductor. The ratio of the minimum wall thickness to the maximum wall thickness, multiplied by 100, shall define the percent concentricity. 4.4.9.1 Test Method Derivation The preceding test method is derived from the Concentricity test method in MIL-W-22759. NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. Page 18 SPECIFICATION 1200, ISSUE 10 4.4.10 Dielectric/Jacket Elongation and Tensile Strength Specimens of the dielectric insulation or cable jacket, as applicable, shall be carefully removed and tested for tensile strength and elongation in accordance with ASTM D3032 using one-inch (25-mm) bench marks, a one-inch (25-mm) initial jaw separation, and a jaw separation speed of two inches (50 mm) per minute, unless specified otherwise on the applicable specification sheet. 4.4.11 Dimensional Stability 4.4. 11.1 Specimen Preparation A 5-foot (1.5-m), minimum, specimen shall be cut. The ends of the specimen shall be cut squarely and the specimen formed into an 18-inch (457-mm) coil. 4.4. 11.2 Procedure Place the specimen in an air-circulating oven and condition for six hours at the applicable test temperature. After the conditioning period, remove the specimen from the oven and condition at room temperature for four hours. Measure both ends of the specimen for protrusion or contraction of the inner conductor. 4.4.11.3 Test Method The preceding test method is derived from the Dimensional Stability test method in MIL-C-17. 4.4.12 Dimensions Measurements shall be made on a 12-inch (305-mm), minimum, length of cable. Inner components shall be made accessible by stripping and removing the outer components carefully so as not to nick, cut, or otherwise damage the component to be measured. Four points for measurement shall be located 3 to 4 inches (76 to 102 mm) apart along the component or finished cable specimen length, as applicable. Measurements shall be made at each point at two approximately perpendicular planes or as required to assure that the minimum and maximum reading is attained at each point. A total of eight measurements shall be performed on each specimen. The minimum, maximum, and average values shall be recorded, as applicable. Measurements shall be made with a micrometer caliper or any other instrument of equal accuracy. 4.4.12.1 Test Method Derivation The preceding test method is derived from the Diameter Measurements test method in MIL-C-17. 4.4.13 Examination of Product All samples shall be examined carefully to determine conformance to this specification and to applicable specification sheets with regard to requirements not covered by specific test methods. NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. SPECIFICATION 1200, ISSUE 10 4.4.14 Page 19 Flammability Flammability shall be tested in accordance with one of the following procedures, as specified in the applicable specification sheet. 4.4.14.1 Flammability - Method A, Vertical Test, Inclined Burner (VW-1) The test shall be performed in accordance with Underwriters Laboratories Subject 1581, Section 1080. 4.4.14.2 Flammability - Method B, 60 Test, Inclined Burner 4.4.14.2.1 Test Apparatus The test shall be performed within a test chamber approximately 1 foot (0.3 m) square by 2 feet (0.6 m) in height, open at the top and front to provide adequate ventilation for combustion but to prevent drafts. The specimen holder shall be so designed that the lower end of a 24-inch (610-mm) specimen is held by a clamp, while the upper end of the specimen passes over a pulley and can be suitably weighted to hold the specimen taut at an angle of 60 degrees with the horizontal, in a plane parallel to and approximately 6 inches (152 mm) from the back of the chamber. The test flame shall originate from a Bunsen-type gas burner with a 0.250-inch (6.4-mm) inlet, a needle valve in the base for gas adjustment, a nominal bore of 0.375 inch (9.5 mm), and a barrel length of approximately 4 inches (102 mm) above the air inlets. The burner shall be adjusted to furnish a 3-inch (76-mm) high conical flame with an inner cone approximately 1 inch (25 mm) in length and a flame temperature not less than 954C at its hottest point, as measured with an accurate thermocouple pyrometer. A sheet of facial tissue conforming to UU-T-450 shall be suspended taut and horizontal 9.5 inches (241 mm) below the point of application of the flame to the specimen and at least 0.50 inch (13 mm) from the chamber floor, so that any material dripping from the specimen shall fall upon the tissue. Pulley 3 in. (75 mm) W eight 8 in. (200 mm) 60 Specimen clamped in place Figure 2. Flammability, Test Apparatus -- Method B, 60 Test, Inclined Burner NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. Page 20 SPECIFICATION 1200, ISSUE 10 4.4.14.2.2 Test Procedure A 24-inch (610-mm) specimen shall be marked at a distance of 8 inches (203 mm) from its lower end to indicate the point for flame application, and shall be placed in the specified 60-degree position in the test chamber. The lower end of the specimen shall be clamped in position in the specimen holder and the upper end shall be passed over the pulley of the holder and the appropriate weight shall be attached. Weight shall be sufficient to hold the specimen taut throughout the test. With the burner held perpendicular to the specimen and at an angle of 30 degrees from the vertical plane of the specimen (see Figure 2), the hottest portion of the flame shall be applied to the lower side of the specimen at the test mark. The period of test flame application shall be 30 seconds and the test flame shall be withdrawn immediately at the end of that period. The distance of flame travel upward along the specimen from the test mark and the time of burning after removal of the test flame shall be recorded; also the presence or absence of flame in the facial tissue due to incendiary dripping from the specimen. Charred holes or charred spots in the tissue shall be ignored in the absence of actual flame. Breaking of the specimens shall not be considered as failure, provided the requirements for flame travel limits, duration of flame, and the absence of incendiary dripping are met. 4.4.14.2.3 Test Method Derivation The preceding test method conforms to FAR Part 25, Appendix F, Part I, and includes a provision for the detection of incendiary dripping. 4.4.14.3 Flammability - Method C, Horizontal Test, Vertical Burner 4.4.14.3.1 Apparatus The test shall be performed within a test chamber approximately 14 inches (365 mm) square by 24 inches (610 mm) in height, open at the top and front to provide adequate ventilation for combustion but to prevent drafts. The chamber shall be equipped with supports 12 inches (305 mm) apart, designed to hold a 15-inch (381-mm) specimen in a taut, horizontal position during the test, and located in a plane parallel to and approximately 6 inches (152 mm) from the back of the chamber. The test flame shall originate from a Tirrill-type gas burner with an 0.25-inch (6.4-mm) inlet, a needle valve in the base for gas adjustment, a nominal bore of 0.38 inch (9.5 mm) and a barrel length of approximately 4 inches (102 mm) above the air inlets. The burner shall be adjusted to furnish a 5-inch (127-mm) high conical flame with an inner cone approximately 1.5 inches (38 mm) in height. NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. SPECIFICATION 1200, ISSUE 10 4.4.14.3.2 Page 21 Procedure A 15-inch (381-mm) specimen shall be placed in a horizontal position in the chamber on supports 12 inches (305 mm) apart. Two strips of indicator paper shall be attached to the specimen 10 inches (254 mm) apart, each paper being 5 inches (127 mm) from the point on the specimen where the inner blue cone of the flame is to be applied. The indicator paper shall be moistened sufficiently for proper adhesion and wrapped once around the specimen, with the gummed side towards the specimen, and the ends pasted evenly together and projected 0.75 inch (19 mm) from the specimen on the opposite side to which the flame is to be applied. The Tirrill burner shall be placed in a vertical position and the flame adjusted to 5 inches (127 mm) in height with the inner blue cone 1.5 inches (38 mm) in height. The burner, in a vertical position, shall be placed so that the inner cone just touches the underside of the specimen at a point midway between the two indicator papers. The flame shall be directed against the specimen for exactly 30 seconds and then removed. After flaming of the specimen has ceased, the indicator papers shall be examined to determine the maximum distance the flame extended in either direction from the center point of application of the flame. 4.4.14.3.3 Test Method Derivation The preceding test method is derived from the Flame Retardance Horizontal test method of CSA Standard C22.2 No. 0.3. 4.4.14.4 Flammability - Method D, 45 Test, Inclined Burner 4.4.14.4.1 Apparatus A gas burner having a 0.5-inch (13-mm) inlet, a nominal core of 0.4 inches (10 mm), and a length of 4 inches (102 mm) above the primary inlets shall be used. The gas burner shall be adjusted to produce a 4-inch (102-mm) gas flame with an inner cone one-half of its height. 4.4.14.4.2 Procedure Suspend a 24-inch (610-mm) test specimen in a draft-free chamber such that the specimen is at a 45-degree angle to the vertical wall of the test chamber. The burner shall perpendicular and in the plane of the specimen. The tip of the inner cone shall be positioned 4 inches (102 mm) from the bottom of the specimen. The flame shall be applied to the specimen for 15 seconds. The afterburn time shall be recorded. 4.4.14.4.3 Test Method Derivation The preceding test method is derived from the Flame Resistance test method in SAE J1128. NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. Page 22 SPECIFICATION 1200, ISSUE 10 Figure 3. Flammability, Test Apparatus -- Method D, 45 Test, Inclined Burner 4.4.15 Heat Shock A 4-inch (102-mm) specimen of finished cable shall be suspended for four hours in an aircirculating oven at the temperature specified in the applicable specification sheet. The oven shall have between 8-20 or 100-200 air changes per hour, and the velocity of air past the specimens shall be between 100 and 200 feet (30 and 61 m) per minute. After conditioning, the specimen shall be removed, cooled to room temperature, and visually examined for evidence of melting or flowing. NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. SPECIFICATION 1200, ISSUE 10 4.4.16 Page 23 Insulation Resistance Insulation resistance shall be measured on samples of finished cable at least 25 feet (7.6 m) in length. A dc potential between 200 and 500 volts shall be applied between each conductor or shield in the cable and all the other conductors and shields. The leakage current shall be measured after a 2-minute electrification period. However, a stable, or an increasing reading indicating compliance with the specification requirement obtained before the 2-minute period shall be acceptable. The insulation resistance of the test specimen shall be calculated from the formula: R= MxL 1000 Where: R = Insulation resistance for 1000 feet in megohms. M = Reading in megohms. L = Test specimen length, in feet, measured between outer conductor ends. 4.4.16.1 Test Method Derivation The preceding test method is derived from the Insulation Resistance test method in MIL-C-17. 4.4.17 Jacket Concentricity and Wall Thickness The concentricity and wall thickness of the cable jacket shall be determined by first locating and recording the minimum wall thickness measured on a cross-section of the jacket. The maximum wall thickness of this same cross-section of jacket shall also be measured and recorded. The wall thickness shall be the radial distance between the inner and outer rim of the jacket as measured under suitable magnification. The ratio of the minimum wall thickness to the maximum wall thickness, multiplied by 100, shall define the percent concentricity. 4.4.17.1 Test Method Derivation The preceding test method is derived from the Concentricity test method in NEMA WC27500. 4.4.18 Jacket Flaws 4.4.18.1 Impulse Test Finished cable shall be tested in accordance with ASTM D3032 at the voltage specified in the applicable specification sheet with the conductor and shield, as applicable, grounded at one end or both ends. When specified in the contract or order, dielectric or jacket failure, untested portions, or portions which have been exposed to fewer or more than the specified pulses may be marked by stripping the insulation or jacket or by any other suitable method of marking as specified in the contract in lieu of being cut out of the cable. NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. Page 24 SPECIFICATION 1200, ISSUE 10 4.4.18.2 Spark Test Finished cable shall be passed through a bead chain electrode spark test device using the voltage and frequency specified in the applicable specification sheet. (Note: 3000 Hz may be used as an alternative for specification sheets specifying a test frequency of 60 Hz. If no frequency is specified, then either 60 or 3000 Hz may be used.) The conductor and shield, as applicable, shall be grounded at one or both ends. The electrode shall be of a suitable bead chain or fine mesh construction that will give intimate metallic contact with practically all the jacket surface. Electrode length and speed of specimen movement shall be such that the jacket is subjected to the test voltage for a minimum of 0.2 second. Any portion showing jacket breakdown shall be cut out including at least 2 inches (51 mm) of cable on each side of the failure. 4.4.18.2.1 Test Method Derivation The preceding test method is derived from the Jacket Flaws test method in NEMA WC27500. 4.4.19 Low Temperature Cold Bend One end of the cable specimen shall be secured to the mandrel specified in the applicable specification sheet and placed in the cold chamber. One full turn shall be wrapped around the mandrel and the opposite end shall have sufficient weight attached to keep the cable vertical and tangent to the mandrel during the bending operation. The chamber shall be lowered to the temperature specified in the applicable specification sheet at a rate not to exceed 50C per minute. The specimen and the mandrel shall be conditioned at this temperature for four hours. At the end of this period, and while both the specimen and mandrel are still at this low temperature, the cable shall be wrapped around the mandrel for 180 degrees without opening the chamber. The time for bending around 180 degrees of the mandrel shall be one-half minute at a uniform rate of speed. A revolving mandrel operated externally from the chamber shall be used. The specimen shall then be removed from the mandrel and visually examined, without magnification, for cracks. The specimen shall then be subjected to the voltage withstand test specified in 4.4.29.2. 4.4.19.1 Test Method Derivation The preceding test method is derived from the Cold Bend test method in NEMA WC27500. 4.4.20 Outer Space Environmental Testing 4.4.20.1 Radiation Resistance A specimen of the finished cable shall be subjected to the electron radiation dosage specified in the applicable specification sheet at an average rate of between 5 and 10 megarads per minute. Following exposure, the center portion of the specimen shall be wound around a mandrel whose diameter is specified in the applicable specification sheet. The ends of the specimen shall extend at least 6 inches (152 mm) beyond the wound portion. The specimen shall be removed from the mandrel without unwinding and shall be subjected to the voltage withstand test of 4.4.29.2. 4.4.20.2 Vacuum Stability Specimens of finished cable shall be tested in accordance with ASTM E595. NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. SPECIFICATION 1200, ISSUE 10 4.4.21 Page 25 Partial Discharge (Corona) Partial discharge extinction voltage (PDEV) shall be defined for this test method as the voltage at which the apparent discharge level falls to 5 picocoulombs or less as the applied voltage is decreased from a value exceeding the inception voltage. 4.4.21.1 Specimen Preparation A length of cable shall be selected such that the sensitivity of the detecting equipment will permit observation of discharges of 5 picocoulombs or less. The specimen shall be as shown in Figure 4. Similar preparation should be made on triaxial cables. Figure 4. Partial Discharge (Corona) Sample Preparation 4.4.21.2 Procedure Connect the specimen to the voltage source so that the voltage is between the conductor and the shield. Triaxial cables shall be connected between the conductor and the first braid. In all cases, the high voltage shall be connected to the conductor or inner shield of the triaxial cable. The frequency of the test voltage shall be between 48 and 62 Hz. The specimen shall be connected to the detecting equipment with the specimen ends immersed in oil until the shield is at least 0.25 inch (6.4 mm) below the surface of the oil. Measurements shall not be made with air bubbles still visible in the oil. Apply the voltage at a maximum rate of 50 volts per second to specimens having a specified PDEV of 3 kV or less, and 100 volts per second for specimens having a specified PDEV above 3 kV. Increase the voltage until partial discharges are detected by the equipment. Then lower the voltage at the same rate until the partial discharges cease. This voltage shall be recorded as the PDEV. NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. Page 26 SPECIFICATION 1200, ISSUE 10 4.4.21.3 Test Method Derivation The preceding test is derived from the Corona Extinction Voltage test method in MIL-C-17. 4.4.22 Propagation Delay Using an appropriate set-up, follow the equipment manufacturer's procedure for measuring propagation delay in nanoseconds per unit length at the frequency specified in the applicable specification sheet. 4.4.23 Shield Coverage 4.4.23.1 Braided Shields The percent optical coverage (OC) of the braided shields shall be determined by the following formula: ( ) OC = 2 F - F 2 x100 Where: F= EPd ECd = sin 2 L sin Where: E P d C L = = = = = = Number of strands per carrier Angle of strands with axis of cable Picks per inch of cable length Diameter of strands (or width, if flat strands are used) Number of carriers Length of lay of strands along cable and tan = 2 ( D +2b) P ( D +2b) = C L Where: b = Diameter of strands (or thickness, if flat strands are used) D = Average diameter of cable under shield (see 4.4.12) NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. SPECIFICATION 1200, ISSUE 10 4.4.23.2 Page 27 Spiral Shields The percent optical coverage (OC) of the spiral shield shall be determined by the following formula: OC = Fx100 Where: F= Ed L sin Where: E d L = = = = Number of strands Diameter of strands (or width, if flat strands are used) Length of lay of strands along the cable Angle of strands with axis of cable and tan = ( D + b) L Where: b = Diameter of strands (or thickness, if flat strands are used) D = Average diameter of cable under the shield (see 4.4.12) 4.4.23.3 Tape Shields The coverage of a tape shield shall be expressed as the percentage by which one turn of the tape overlaps the previous turn, and shall be determined by the following formula: Overlap = a x100% b Where: a = Distance, measured perpendicular to the edge of the tape, by which one turn of the tape overlaps the next b = Width of the tape Alternatively: c Overlap = 1 - x100% d Where: c = Distance between adjacent visible tape edges measured along the axis of the cable d = Width of the tape measured along the axis of the cable NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. Page 28 SPECIFICATION 1200, ISSUE 10 4.4.23.4 Test Method Derivation The preceding test methods are derived from the Shield Coverage test method in NEMA WC27500. 4.4.24 Skew A sample of appropriate length shall be tested for skew in accordance with the equipment manufacturer's procedure. Skew shall be reported in nanoseconds per unit length at the frequency shown in the specification sheet. 4.4.25 Structural Return Loss 4.4.25.1 Specimen Preparation The specimen shall be of sufficient length to exhibit at least 3 dB attenuation at the lowest frequency required, unless otherwise specified. The specified connectors shall be attached to both ends of the specimen and the assembly connected to a TDR that is capable of producing a step-function rise-time of 150 picoseconds or less. With the far end of the specimen connected to a matched load, the impedance variation exhibited by each cable connector-cable interface shall not be greater than the maximum impedance variation permitted for the cable itself. 4.4.25.2 Procedure An appropriate test set shall be used to measure the structural return loss of the sample. Calibration and specimen measurements shall be made in accordance with the analyzer or system procedures. The return loss shall be recorded over the specified frequency range. 4.4.25.3 Determination of Compliance Within the frequency range(s) specified on the applicable specification sheet, the structural return loss shall not be greater than the specified value. (Note: Structural Return Loss is measured in dB. This measurement may be reported as SWR or VSWR and expressed as a ratio.) 4.4.25.4 Test Method Derivation The preceding test method is derived from the Structural Return Loss test method in MIL-C-17. 4.4.26 Surface Transfer Impedance 4.4.26.1 Sample Preparation Approximately 4 feet (1.2 m) of the cable shall be prepared in the manner described below. Any method of shield termination may be used provided the method is shown to produce results of equal accuracy to that obtained with the method described below. NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. SPECIFICATION 1200, ISSUE 10 4.4.26.1.1 Page 29 End A Preparation (See Figure 5). Approximately 3 inches (75 mm) of the cable jacket shall be removed from one end of the cable and the shield pushed back to expose the insulated conductor. The insulation shall be removed from the conductor to within 1 inch (25 mm) of the pushed-back shield as shown in Figure 5, Step 1. For a multiconductor cable, connect all the conductors together to form a single "conductor". The shield shall then be pulled forward over the remaining insulation and soldered to the conductor. The shield shall completely enclose the insulated conductor, shall be soldered around 360 degrees of the conductor, and all disturbed portions of the shield shall be well soldered. The conductor shall extend beyond the soldered joint with the shield and shall be formed and trimmed so as to be able to be soldered into the center pin of a BNC female-female adapter as shown in Figure 5, Step 2. Excess shield beyond the solder joint shall be removed, and the center pin of the adapter shall be attached to the conductor so that the pin is within 0.5 inch (12.5 mm) of the soldered joint. From the soldered joint, measure 1 meter and make an appropriate mark on the jacket insulation. A piece of shrink tubing or other appropriate material shall be applied over the soldered joint to insulate the joint as shown in Figure 5, Step 3. The adapter pin shall then be inserted into the BNC adapter as shown in Figure 5, Step 4. A metallic outer braid shall be pulled over the entire length of cable and shall extend one-third over the BNC adapter. The outer braid shall then be soldered to the BNC adapter, making sure that a 360-degree solder joint is formed as shown in Figure 5, Step 5. 4.4.26.1.2 End B Preparation (See Figure 6). At the other end of the cable, push back the outer braid, over the cable, to expose the mark made 1 meter from the end A conductor solder joint. At the mark, the cable jacket shall be window-stripped for a distance of 0.5 inch (12.5 mm), 0.25 inch (6 mm) on either side of the mark as shown in Figure 6, Step 1. The outer shield shall then be pulled taut back over the cable and twisted at the end of the cable to hold the outer braid in place. The outer braid shall be soldered to the underlying exposed shield for 360degrees around the cable at the window cut. Excess outer braid between the solder joint and the end of the cable shall be removed as shown in Figure 6, Step 2. Shrink tubing shall be applied over the entire length of outer braid ensuring that the braid is pressed firmly to the jacket as shown in Figure 5, Step 6. Excess heat shrink tubing shall be removed. The end of the cable shall then be cut and prepared for termination to the Nmale connector such that the distance from the installed connector to the window in the cable jacket is as close as possible as shown in Figure 6, Step 3 and Figure 6, Step 4. For multiconductor cables, one conductor shall be prepared for termination to the N connector, the other conductors shall be floating. (Floating conductors in a multiconductor cable is achieved by applying shrink tubing to the exposed ends of the unused conductors.) NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. Page 30 SPECIFICATION 1200, ISSUE 10 Figure 5. Preparation of Cable End A NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. SPECIFICATION 1200, ISSUE 10 Page 31 Step 1 Step 2 Step 3 Step 4 Figure 6. Preparation of Cable End B 4.4.26.2 Configuration An appropriate test set shall be used to measure the surface transfer impedance of the sample. Signal Generator 10 dB Pad Detector Specimen A B Figure 7. Configuration of the measurement system for determining surface transfer impedance. The letters "A" and "B" refer to the A and B ends of the specimen as described in paragraph 4.4.26.1. NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. Page 32 SPECIFICATION 1200, ISSUE 10 4.4.26.3 Procedure This measurement procedure is suitable for use with a spectrum analyzer and tracking generator. The measurement procedure may be modified as needed if other instruments are used, provided the results are shown to be of equal accuracy to those obtained when the measurements are performed as described below. With the measuring system configured as shown in Figure 7, adjust the output of the signal generator to produce a trace on the spectrum analyzer, which at its highest point is near the top graticule line on the screen. Remove the specimen and insert a calibrated variable attenuator in its place. Adjust the attenuator until a trace is obtained which approximates the top graticule on the screen. The position of the trace shall be recorded, either by storage on the screen or in any other suitable manner. Designate this trace A0, where A0 is the setting of the attenuator in dB. Increase the attenuator setting by 20 dB, and record the position of this trace, designated A20, where A20 is the setting of the attenuator in dB. Increase the attenuator further by 20 dB, and record the position of a trace designated A40. Continue in this manner until the calibration traces have covered the entire height of the screen. Remove the attenuator, and reconnect the specimen as shown in Figure 7. Designate the resulting trace on the screen as S and record its position. The value of S at any frequency shall then be calculated using the following equation: y S = Au + 20 dB m h Where: Au = Attenuator setting used to produce the calibration trace immediately above trace S. y = Distance on the screen between the traces Au and S. h = Distance on the screen between trace Au and the calibration trace immediately below trace S. The power of attenuation P of the shield is: P = 10 S 10 The surface transfer impedance Zt, at the frequency chosen, is given by: Zt = Z0 2 P ohms / meter Where: Z0 = Characteristic impedance of the spectrum analyzer and tracking generator. Unless otherwise specified, 100 points uniformly spaced throughout the decade of frequency, and including the beginning and end of the decade, shall be taken for each decade of frequency range specified on the specification sheet. NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. SPECIFICATION 1200, ISSUE 10 4.4.26.4 Page 33 Determination of Compliance The values of Zt, as determined from measurements made in accordance with 4.4.26.3, shall not exceed the maximum specified values of Zt as shown on the applicable specification sheet in any of the following ways: a. A single maximum value of Zt may be specified at a discrete frequency or over a range of frequencies. b. The maximum value of Zt over a range of frequencies may be specified by a plot of the maximum value of Zt versus frequency. c. The maximum value of Zt over a range of frequencies specified by a curve defined by the maximum value of Zt at given frequencies. d. The maximum value of Zt over a range of frequencies may be specified by the equation: Maximum specified Z t = Az ( f ) Bz milliohms / meter, Where: f = Frequency in MHz Az, Bz = Zt calculation parameters given on the specification sheet 4.4.26.5 Test Method Derivation The preceding test method is derived from the Surface Transfer Impedance test method in MIL-C-85485. 4.4.27 Time Delay Time delay (TD), in nanoseconds per foot, shall be determined by the formula: TD = 10167 . Vp(%) Where: Vp = Velocity of propagation as determined by 4.4.28. 4.4.28 Velocity of Propagation 4.4.28.1 Specimen Preparation The sample cable shall be of suitable length, 10 feet (3 m), minimum. At one end of the cable, the center conductor and shield shall be connected together. For a twisted pair, the conductors shall be twisted together and the shield left unconnected. At the other end of the cable, one conductor shall be designated as the center conductor and the other conductor as the outer conductor. The sample length shall be defined as the length of cable covered by the shield. For an unshielded twisted pair, tape the components together one-half inch (12.5 mm) from each end of the cable. The sample length shall be defined as the length of cable between the outside edges of the tape. The sample length shall be measured and designated as L. NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. Page 34 SPECIFICATION 1200, ISSUE 10 4.4.28.2 Procedure The free end of the cable shall be attached to a `T'-type connector. One leg of the T shall be attached to a detector and the other leg to a signal generator. The signal generator shall be adjusted to a frequency of 1 MHz and the frequency shall then be increased until a sharp decrease in the detector reading is observed. The frequency generator shall be adjusted until a minimum in the detector reading is achieved. This frequency shall be recorded to the nearest 0.1 MHz. Designate this reading as f1. The frequency of the signal generator shall be increased further until another decrease in the detector reading is observed. The frequency of the minimum detector reading shall be recorded as f2. This procedure shall be repeated until at least four different frequencies are recorded. 4.4.28.3 Calculations At each recorded frequency, the frequency in MHz shall be divided by the subscript number and the results recorded. f 1 1= f 01 f 2 2 = f 02 f 3 3 = f 03 f 4 4 = f 04 etc. _ The mean value of all the resulting frequencies shall be calculated and designated as f . The velocity of propagation (Vp) shall be determined from the formula: Vp = _ _ 2 Lm f 299.8 2 Lf f or 983.6 % Where: Lm = Specimen length in meters Lf = Specimen length in feet 4.4.28.4 Test Method Derivation The preceding test method is derived from the Time Delay test method in MIL-C-17. 4.4.29 Voltage Withstand Voltage withstand tests shall be made using an ac source with a frequency of 50 to 60 Hz. The voltage applied shall be as specified on the applicable specification sheet and shall be applied for one minute. NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. SPECIFICATION 1200, ISSUE 10 4.4.29.1 Page 35 Voltage Withstand (Dielectric) Voltage withstand (dielectric) tests shall be performed upon finished cable by applying the specified voltage between each conductor or shield in turn, and all other conductors and shields which shall be tied together and grounded. 4.4.29.2 Voltage Withstand (Post-Environmental) Voltage withstand (post-environmental) tests on the outer jacket shall be performed after the finished cable has been immersed in water for at least one hour and while the cable is still immersed. The specified voltage shall be applied between all the conductors and shields, tied together, and the water bath which shall be grounded. 4.4.29.3 Test Method Derivation The preceding test methods are derived from the Dielectric Withstand and Voltage Withstand, Jacket, test methods in NEMA WC27500. 4.4.30 Weight The weight of each lot of finished cable shall be determined by Procedure I (4.4.30.1). Lots failing to meet the weight requirement of the applicable specification sheet when tested in accordance with Procedure I shall be subjected to Procedure II (4.4.30.2). All reels or spools failing to meet the requirements of the applicable specification sheet when tested by Procedure II shall be rejected. 4.4.30.1 Procedure I A length of cable, sufficient to produce a measured weight to at least 3 significant figures, shall be weighed and converted to the weight per unit length shown on the applicable specification sheet. 4.4.30.2 Procedure II The net weight of the finished cable on each reel or spool shall be obtained by subtracting the tare weight of the reel or spool from the gross weight of the reel or spool containing the finished cable. The net weight of cable on each reel or spool shall be divided by the accurately determined length of finished cable on that reel or spool and the resultant figure converted to pounds per 1000 feet (kg/km). When wood or other moisture absorbent materials are used for reel or spool construction, weight determinations shall be made under substantially uniform conditions of relative humidity. 4.4.30.3 Test Method Derivation The preceding test methods are derived from the Wire Weight test methods in MIL-W-22759. NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. Page 36 SPECIFICATION 1200, ISSUE 10 5 PREPARATION FOR DELIVERY 5.1 PACKAGING AND PACKING Cable shall be delivered wound on reels or spools in accordance with 5.1.1 and in such a manner that all ends are accessible. Only identical type cable lengths shall be contained in any one package unit. 5.1.1 Reels and Spools Reels and spools shall be of a nonreturnable type. Each reel and spool shall have an appropriate diameter for the respective cable size. In no case shall the barrel of the reel or spool have a diameter less than 3 inches (76 mm). Reels and spools shall be suitably finished to prevent corrosion under typical storage and handling conditions. 5.1.2 Containers Unless otherwise specified (see 6.1), cable shall be delivered in standard commercial containers, so constructed as to ensure acceptance by common or other carrier for safe transportation at the lowest rate to the point of delivery. 5.2 MARKING OF SHIPMENTS Unless otherwise specified in the contract or purchase order, each reel or spool shall be legibly marked with the following information: Manufacturer's Part Number Lot Number Quantity in Feet (or Meters) Name of Manufacturer 6 NOTES 6.1 ORDERING DATA Procurement documents should specify the following: a. b. c. d. 6.2 Title and number of this specification Applicable specification sheet part number Quantity Special preparation for delivery requirements, if applicable METRIC UNITS Metric units, where shown in parentheses, are for information only. 6.3 TEST METHOD DERIVATIONS Test method derivations contained in test methods are shown for information only. NOTE: ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. SPECIFICATION 1200, ISSUE 10 6.4 Page 37 SYMBOLS The following symbols and prefixes are used in this specification and are listed below for information. 6.4.1 6.4.2 Standard Prefixes Symbol Prefix M k d c m n p f mega kilo deci centi milli micro nano pico femto Multiplier 106 103 10-1 10-2 10-3 10-6 10-9 10-12 10-15 Standard Symbols Symbol B Bm C C F eV ft. F g Hz in. m psi s V NOTE: Name bel bel (relative to 1 milliwatt) coulomb degrees, Celsius degrees, Fahrenheit electron-volt foot farad gram hertz inch meter pounds per square inch second volt ohm ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY. Page 38 SPECIFICATION 1200, ISSUE 10 6.4.4 Electrical Symbols Symbol a1, a2 ac A0, A20,... A(f) Au Az Bz C Ca, Cb, Cc, Cd Cag, Cbg Cap, Cbp Cm Cu Cu1, Cu2, etc. CuL Cupg CRAL dc f f1, f2,... h L M P PDEV R S SWR TD TDR VSWR Vp y Y Y1 Zin Zo Zos Zsc Zref Zt u NOTE: Description Attenuation formula coefficients Alternating current Calibrated attenuator settings, dB Attenuation at frequency (f) Calibrated attenuator setting, dB Zt calculation parameter Zt calculation parameter Calculated or measured capacitance Measured capacitances Measured capacitance, conductor to ground Measured capacitance, conductor to pair Mutual capacitance, calculated Capacitance unbalance, calculated Capacitance unbalance, % Pair-to-pair capacitance unbalance, measured Pair-to-ground capacitance unbalance, calculated Calibrated reference air line Direct current Frequency (MHz) Resonant frequency (MHz) Measurement on spectrum analyzer screen Calculated or measured inductance Leakage current reading in megohms Power ratio Partial discharge extinction voltage Insulation resistance, calculated Calculated attenuation Standing wave ratio Time delay Time domain reflectometer Voltage standing wave ratio Velocity of propagation, % Measurement on spectrum analyzer screen Pair-to-ground capacitance unbalance, measured Pair-to-ground capacitance unbalance per 1000 feet (km) Input impedance Characteristic impedance Open circuit impedance, measured Short circuit impedance, measured Reference characteristic impedance Surface transfer impedance Reflection coefficient, calculated Reflection coefficient, un-scaled ANY COPY OF THIS DOCUMENT THAT DOES NOT HAVE A RED "CONTROL" STAMP IS AN UNCONTROLLED COPY.