UNITED STATES DEPARTMENT OF AGRICULTURE

Rural Electrification Administration

BULLETIN 1753F-207(PE-87)

RD-GD-1994-16

Wally Beyer 7/14/94

________________________________________ ___________________

Administrator Date

SUBJECT: REA Specification for Terminating Cables

TO: All Telephone Borrowers

REA Telephone Staff

EFFECTIVE DATE: July 14, 1994.

EXPIRATION DATE: Date of change in 7 CFR 1755.870 by rulemaking.

OFFICE OF PRIMARY INTEREST: Outside Plant Branch,

Telecommunications Standards Division.

PREVIOUS INSTRUCTIONS: This bulletin replaces REA Bulletin

345-87, REA Specification for Terminating (TIP) Cable, PE-87,

issued December 19, 1983.

FILING INSTRUCTIONS: Discard REA Bulletin 345-87, REA

Specification for Terminating (TIP) Cable, PE-87, dated

December 19, 1983, and replace with this bulletin. File with 7

CFR 1755 and on REANET.

PURPOSE: This specification covers REA requirements for

terminating cables intended primarily to connect incoming outside

plant cable to the vertical side of the main distributing frame

in a telephone central office. This bulletin is a user friendly

guide and a reformat of the text codified in 7 CFR 1755.870

published at 59 FR 30505, dated June 14, 1994.

Every effort has been made to ensure the accuracy of this

document. However, in case of discrepancies, the regulations at

7 CFR 1755.870 are the authorized sources.

Disclaimer: The contents of this guidance document does not 

have the force and effect of law and is not meant to bind the 

public in any way. This document is intended only to provide 

clarity to the public regarding existing requirements under 

the law or agency policies.
Bulletin 1753F-207(PE-87)

Page 2

TABLE OF CONTENTS

CFR to Bulletin Conversion Table..........................3

Abbreviations.............................................5

1. Scope.....................................................6

2. Conductors and Conductor Insulation.......................6

3. Identification of Pairs and Twisting of Pairs............10

4. Forming of the Cable Core................................11

5. Core Wrap................................................13

6. Shield...................................................13

7. Cable Jacket and Extraneous Material.....................15

8. Electrical Requirements..................................17

9. Mechanical Requirements..................................21

10. Sheath Slitting Cord (Optional)..........................21

11. Identification Marker and Length Marker..................21

12. Preconnectorized Cable (Optional)........................23

13. Acceptance Testing and Extent of Testing.................23

14. Summary of Records of Electrical and Physical Tests......25

15. Manufacturing Irregularities.............................25

16. Preparation for Shipment.................................25

APPENDIX A: Qualification Test Methods......................27

APPENDIX B: Sheath Slitting Cord Qualification..............35

INDEX:

Cable, Terminating, Telephone
Bulletin 1753F-207(PE-87)

Page 3

CFR TO BULLETIN CONVERSION TABLE

7 CFR Bulletin 7 CFR Bulletin 7 CFR Bulletin

1755.870 1753F-207 1755.870 1753F-207 1755.870 1753F-207

 (a) 1. (d)(3) 4.3 (h)(1)(iii) 8.1.3

 (a)(1) 1.1 (d)(4) 4.4 (h)(2) 8.2

 (a)(1)(i) 1.1.1 (d)(5) 4.5 (h)(3) 8.3

 (a)(1)(ii) 1.1.2 (d)(6) 4.6 (h)(3)(i) 8.3.1

 (a)(1)(iii) 1.1.3 (d)(7) 4.7 (h)(3)(ii) 8.3.2

 (a)(2) 1.2 (d)(8) 4.8 (h)(3)(iii) 8.3.3

 (a)(3) 1.3 (e) 5. (h)(4) 8.4

 (a)(4) 1.4 (e)(1) 5.1 (h)(4)(i) 8.4.1

 (b) 2. (e)(2) 5.2 (h)(4)(ii) 8.4.2

 (b)(1) 2.1 (e)(3) 5.3 (h)(4)(iii) 8.4.3

 (b)(2) 2.2 (f) 6. (h)(5) 8.5

 (b)(3) 2.3 (f)(1) 6.1 (h)(6) 8.6

 (b)(4) 2.4 (f)(2) 6.2 (h)(6)(i) 8.6.1

 (b)(5) 2.5 (f)(3) 6.3 (h)(6)(ii) 8.6.2

 (b)(5)(i) 2.5.1 (f)(4) 6.4 (h)(7) 8.7

 (b)(5)(ii) 2.5.2 (f)(4)(i) 6.4.1 (h)(8) 8.8

 (b)(5)(iii) 2.5.3 (f)(4)(ii) 6.4.2 (h)(8)(i) 8.8.1

 (b)(5)(iv) 2.5.4 (f)(4)(iii) 6.4.3 (h)(8)(ii) 8.8.2

 (b)(5)(v) 2.5.5 (f)(4)(iv) 6.4.4 (h)(9) 8.9

 (b)(6) 2.6 (f)(4)(v) 6.4.5 (h)(9)(i) 8.9.1

 (b)(7) 2.7 (f)(4)(vi) 6.4.6 (h)(9)(ii) 8.9.2

 (b)(8) 2.8 (f)(5) 6.5 (h)(9)(iii) 8.9.3

 (b)(8)(i) 2.8.1 (f)(6) 6.6 (i) 9.

 (b)(8)(ii) 2.8.2 (f)(7) 6.7 (i)(1) 9.1

 (b)(8)(iii) 2.8.3 (f)(8) 6.8 (i)(2) 9.2

 (b)(8)(iv) 2.8.4 (f)(8)(i) 6.8.1 (i)(3) 9.3

 (b)(8)(v) 2.8.5 (f)(8)(ii) 6.8.2 (j) 10.

 (b)(9) 2.9 (f)(9) 6.9 (j)(1) 10.1

 (b)(10) 2.10 (f)(9)(i) 6.9.1 (j)(2) 10.2

 (b)(11) 2.11 (f)(9)(ii) 6.9.2 (j)(3) 10.3

 (b)(12) 2.12 (f)(9)(iii) 6.9.3 (k) 11.

 (b)(12)(i) 2.12.1 (g) 7. (k)(1) 11.1

 (b)(12)(ii) 2.12.2 (g)(1) 7.1 (k)(2) 11.2

 (b)(12)(iii) 2.12.3 (g)(2) 7.2 (k)(3) 11.3

 (b)(12)(iv) 2.12.4 (g)(3) 7.3 (k)(4) 11.4

 (b)(12)(v) 2.12.5 (g)(4) 7.4 (k)(5) 11.5

 (b)(13) 2.13 (g)(5) 7.5 (k)(6) 11.6

 (c) 3. (g)(5)(i) 7.5.1 (k)(7) 11.7

 (c)(1) 3.1 (g)(5)(ii) 7.5.2 (k)(8) 11.8

 (c)(2) 3.2 (g)(5)(iii) 7.5.3 (k)(9) 11.9

 (c)(3) 3.3 (g)(6) 7.6 (k)(10) 11.10

 (c)(4) 3.4 (g)(6)(i) 7.6.1 (k)(11) 11.11

 (c)(5) 3.5 (g)(6)(ii) 7.6.2 (l) 12.

 (c)(6) 3.6 (g)(7) 7.7 (l)(1) 12.1

 (c)(7) 3.7 (g)(8) 7.8 (l)(2) 12.2

 (c)(8) 3.8 (h) 8. (m) 13.
Bulletin 1753F-207(PE-87)

Page 4

 (d) 4. (h)(1) 8.1 (m)(1) 13.1

 (d)(1) 4.1 (h)(1)(i) 8.1.1 (m)(2) 13.2

 (d)(2) 4.2 (h)(1)(ii) 8.1.2 (m)(3) 13.3

CFR TO BULLETIN CONVERSION TABLE

7 CFR Bulletin 7 CFR Bulletin

1755.870 1753F-207 1755.870 1753F-207

(m)(4) 13.4 (II)(1) 2.1

(m)(5) 13.5 (II)(1)(a) 2.1.1

(m)(5)(i) 13.5.1 (II)(1)(b) 2.1.2

(m)(5)(ii) 13.5.2 (II)(1)(c) 2.1.3

(m)(5)(iii) 13.5.3 (II)(2) 2.2

(m)(5)(iv) 13.5.4 (III) 3.

(m)(5)(v) 13.5.5 (III)(1) 3.1

(m)(5)(vi) 13.5.6 (III)(1)(a) 3.1.1

(m)(5)(vii) 13.5.7 (III)(1)(b) 3.1.2

(m)(6) 13.6 (III)(1)(c) 3.1.3

(m)(6)(i) 13.6.1 (III)(1)(d) 3.1.4

(m)(6)(ii) 13.6.2 (III)(1)(e) 3.1.5

(m)(6)(iii) 13.6.3 (III)(2) 3.2

(m)(6)(iv) 13.6.4 (III)(2)(a) 3.2.1

(m)(6)(v) 13.6.5 (III)(2)(b) 3.2.2

(m)(6)(vi) 13.6.6 (III)(3) 3.3

(m)(6)(vii) 13.6.7 (III)(3)(a) 3.3.1

(m)(6)(viii) 13.6.8 (III)(3)(b) 3.3.2

(n) 14. (III)(3)(c) 3.3.3

(n)(1) 14.1 (IV) 4.

(n)(2) 14.2 (IV)(1) 4.1

(o) 15. (IV)(2) 4.2

(o)(1) 15.1 (IV)(3) 4.3

(o)(2) 15.2 (IV)(3)(a) 4.3.1

(p) 16. (IV)(3)(b) 4.3.2

(p)(1) 16.1 (IV)(3)(c) 4.3.3

(p)(2) 16.2 (V) 5.

(p)(3) 16.3 APPENDIX B APPENDIX B

(p)(4) 16.4 (I) 1.

(p)(5) 16.5 (II) 2.

(p)(6) 16.6 (III) 3.

(p)(7) 16.7 (III)(1) 3.1

(p)(8) 16.8 (III)(2) 3.2

APPENDIX A APPENDIX A (III)(3) 3.3

(I) 1. (III)(4) 3.4

(II) 2. (III)(5) 3.5
Bulletin 1753F-207(PE-87)

Page 5

ABBREVIATIONS

ANSI American National Standards Institute

ASTM American Society For Testing and Materials

AWG American Wire Gauge

°C Centigrade temperature scale

CMR Communication Riser Cable

dB Decibel

dB/1000 ft Decibels per 1000 feet

dB/km Decibels per 1 kilometer

dc Direct current

EIA Electronic Industries Association

Fo Known frequency

Fx New frequency

FEXT Far-end crosstalk

ft Feet

in. Inches

in./min Inches per 1 minute

IR Insulation resistance

Ko Known far-end crosstalk

Kx New far-end crosstalk

km Kilometer

kHz Kilohertz

Lo Known length

Lx New length

lbf Pound force

m Meter

M-S Mean minus sigma

Max. Maximum

Min. Minimum

micromhos/km Micromhos per 1 kilometer

MPa Megapascals

mm Millimeter

mm/min Millimeters per 1 minute

N Newton

NEXT Near-end crosstalk

nF/km Nanofarad per 1 kilometer

nF/mile Nanofarad per 1 mile

ohms/1000 ft Ohms per 1000 feet

% Percent

pF/km Picofarads per 1 kilometer

pF/1000 ft Picofarads per 1000 feet

psi Pounds per square inch

PVC Polyvinyl Chloride

REA Rural Electrification Administration

rms Root mean square

UL Underwriters Laboratory
Bulletin 1753F-207(PE-87)

Page 6

1. SCOPE

1.1 This specification establishes the requirements for

terminating cables used to connect incoming outside plant cables

to the vertical side of the main distributing frame in a

telephone central office.

1.1.1 The conductors are solid tinned copper, individually

insulated with extruded solid dual insulating compounds.

1.1.2 The insulated conductors are twisted into pairs which are

then stranded or oscillated to form a cylindrical core.

1.1.3 The cable structure is completed by the application of a

core wrap, a shield, and a polyvinyl chloride jacket.

1.2 The number of pairs and gauge size of conductors which are

used within the REA program are provided in the following table:

American Wire Gauge (AWG) 22 24

Pairs 12 12

50 50

100 100

200 200

300 300

400 400

600 600

800 800

Note: Cables larger in pairs from those shown in this table

shall meet all the requirements of this specification.

1.3 All cables sold to REA borrowers for projects involving REA

loan funds under this specification must be accepted by REA

Technical Standards Committee "A" (Telephone). For cables

manufactured to this specification, all design changes to an

accepted design must be submitted for acceptance. REA will be

the sole authority on what constitutes a design change.

1.4 Materials, manufacturing techniques, or cable designs not

specifically addressed by this specification may be allowed if

accepted by REA. Justification for acceptance of modified

materials, manufacturing techniques, or cable designs shall be

provided to substantiate product utility and long term stability

and endurance.

2. CONDUCTORS AND CONDUCTOR INSULATION

2.1 Each conductor shall be a solid round wire of commercially

pure annealed tin coated copper. Conductors shall meet the
Bulletin 1753F-207(PE-87)

Page 7

requirements of the American Society for Testing and Materials

(ASTM) B 33-91 except that requirements for Dimensions and

Permissible Variations are waived.

2.2 Joints made in conductors during the manufacturing process

may be brazed, using a silver alloy solder and nonacid flux, or

they may be welded using either an electrical or cold welding

technique. In joints made in uninsulated conductors, the two

conductor ends shall be butted. Splices made in insulated

conductors need not be butted but may be joined in a manner

acceptable to REA.

2.3 The tensile strength of any section of a conductor,

containing a factory joint, shall not be less than 85 percent of

the tensile strength of an adjacent section of the solid

conductor of equal length without a joint.

2.4 Engineering Information: The sizes of wire used and their

nominal diameters shall be as shown in the following table:

Nominal Diameter

AWG millimeters (inches)

22 0.643 (0.0253)

24 0.511 (0.0201)

2.5 Each conductor shall be insulated with a primary layer of

natural or white solid, insulating grade, high density

polyethylene or crystalline propylene/ethylene copolymer and an

outer skin of colored, solid, insulating grade, polyvinyl

chloride (PVC) using one of the insulating materials listed in

Paragraphs 2.5.1 through 2.5.3 of this specification.

2.5.1 The polyethylene raw material selected to meet the

requirements of this specification shall be Type III,

Class A, Category 4 or 5, Grade E9 in accordance with

ASTM D 1248-84(1989).

2.5.2 The crystalline propylene/ethylene raw material selected

to meet the requirements of this specification shall be

Class PP 200B 40003 E11 in accordance with ASTM D 4101-82(1988).

2.5.3 The PVC raw materials selected to meet the requirements of

this specification shall be either Type PVC-64751E3X0,

Type PVC-76751E3X0, or TYPE PVC-77751E3X0 in accordance with

ASTM D 2287-81(1988).

2.5.4 Raw materials intended as conductor insulation furnished

to these requirements shall be free from dirt, metallic

particles, and other foreign matter.

2.5.5 All insulating raw materials shall be accepted by REA

prior to their use.
Bulletin 1753F-207(PE-87)

Page 8

2.6 All conductors in any single length of cable shall be

insulated with the same type of material.

2.7 A permissible overall performance level of faults in

conductor insulation when using the test procedures in Paragraph

2.8 of this specification shall average not greater than one

fault per 12,000 conductor meters (40,000 conductor feet) for

each gauge of conductor.

2.8 The test used to determine compliance with Paragraph 2.7 of

this specification shall be conducted as follows:

2.8.1 Samples tested shall be taken from finished cables

selected at random from standard production cable. The samples

tested shall contain a minimum of 300 conductor meters (1,000

conductor feet) for cable sizes less than 50 pairs and 1,500

conductor meters (5,000 conductor feet) for cable sizes greater

than or equal to 50 pairs. No further sample need be taken from

the same cable production run within 6,000 cable meters (20,000

cable feet) of the original test sample from that run.

2.8.2 The cable sample shall have its jacket, shield, and core

wrap removed and its core shall be immersed in tap water for a

minimum period of 6 hours. In lieu of removing the jacket,

shield, and core wrap from the core, the entire cable may be

tested. In this case, the core shall be completely filled with

tap water, under pressure; then the cable assembly shall be

immersed for a minimum period of 6 hours. With the cable core

still fully immersed, except for end connections, the insulation

resistance (IR) of all conductors to water shall be measured

using a direct current (dc) voltage of 100 volts to 550 volts.

2.8.3 An IR value of less than 500 megohms for any individual

insulated conductor tested at or corrected to a temperature of

23°C is considered a failure. If the cable sample is more than

7.5 meters (25 feet) long, all failing conductors shall be

retested and reported in 7.5 meter (25 foot) segments.

2.8.4 The pair count, gauge, footage, and number of insulation

faults shall be recorded. This information shall be retained on

a 6 month running basis for review by REA when requested.

2.8.5 A fault rate, in a continuous length in any one reel, in

excess of one fault per 3,000 conductor meters (10,000 conductor

feet) due to manufacturing defects is cause for rejection. A

minimum of 6,000 conductor meters (20,000 conductor feet) is

required to develop a noncompliance in a reel.

2.9 Repairs to the conductor insulation during manufacturing are

permissible. The method of repair shall be accepted by REA prior

to its use. The repaired insulation shall be capable of meeting

the relevant electrical requirements of this specification.
Bulletin 1753F-207(PE-87)

Page 9

2.10 All repaired sections of insulation shall be retested in

the same manner as originally tested for compliance with the

Paragraph 2.7 of this specification.

2.11 The colored composite insulating material removed from or

tested on the conductor, from a finished cable, shall be capable

of meeting the following performance requirements:

Property Composite Insulation

Tensile Strength

Minimum, Megapascals

(MPa) (Pounds per square

inch (psi)) 16.5 (2,400)

Ultimate Elongation

Percent, Minimum 125

Cold Bend

Failures, Maximum 0/10

Shrinkback

Maximum, Millimeters

(mm) (Inches (in.)) 9.5 (3/8)

Adhesion

Maximum, Newtons (N)

(Pound-force (lbf)) 13.3 (3)

Compression

Minimum, N (lbf) 1780 (400)

2.12 Testing Procedures: The procedures for testing the

composite insulation samples for compliance with Paragraph 2.11

of this specification shall be as follows:

2.12.1 Tensile Strength and Ultimate Elongation: Samples of the

insulation material, removed from the conductor, shall be tested

in accordance with ASTM D 2633-82(1989), except that the speed of

jaw separation shall be 50 millimeters/minute (50 mm/min)

(2 inches/minute (2 in./min)).

Note: Quality assurance testing at a jaw separation speed

of 500 mm/min (20 in./min) is permissible. Failures at this rate

shall be retested at the 50 mm/min (2 in./min) rate to determine

specification compliance.

2.12.2 Cold Bend: Samples of the insulation material on the

conductor shall be tested in accordance with ASTM D 4565-90a at a

temperature of -40 ± 1°C with a mandrel diameter of 6 mm

(0.25 in.). There shall be no cracks visible to normal or

corrected-to-normal vision.
Bulletin 1753F-207(PE-87)

Page 10

2.12.3 Shrinkback: Samples of insulation shall be tested for

four hours at a temperature of 115 ± 1°C in accordance with

ASTM D 4565-90a.

2.12.4 Adhesion: Samples of the insulation material on the

conductor shall be tested in accordance with ASTM D 4565-90a with

a crosshead speed of 50 mm/min (2 in./min).

2.12.5 Compression: Samples of the insulation material on the

conductor shall be tested in accordance with ASTM D 4565-90a with

a crosshead speed of 5 mm/min (0.2 in./min).

2.13 Other methods of testing may be used if acceptable to REA.

3. IDENTIFICATION OF PAIRS AND TWISTING OF PAIRS

3.1 The PVC skin shall be colored to identify:

a. The tip and ring conductor of each pair; and

b. Each pair in the completed cable.

3.2 The colors used to provide identification of the tip and

ring conductor of each pair shall be as shown in the following

table:

Color

Pair No. Tip Ring

1 White Blue

2 White Orange

3 White Green

4 White Brown

5 White Slate

6 Red Blue

7 Red Orange

8 Red Green

9 Red Brown

10 Red Slate

11 Black Blue

12 Black Orange

13 Black Green

14 Black Brown

15 Black Slate

16 Yellow Blue

17 Yellow Orange

18 Yellow Green

19 Yellow Brown

20 Yellow Slate
Bulletin 1753F-207(PE-87)

Page 11

21 Violet Blue

22 Violet Orange

23 Violet Green

24 Violet Brown

25 Violet Slate

3.3 Standards of Color: The colors of the insulated conductors

supplied in accordance with this specification are specified in

terms of the Munsell Color System (ASTM D 1535-89) and shall

comply with the "Table of Wire and Cable Limit Chips" as defined

in ANSI/EIA-359-A-84. (Visual color standards meeting these

requirements may be obtained directly from the Munsell Color

Company, Inc., 2441 North Calvert Street, Baltimore, Maryland

21218).

3.4 Positive identification of the tip and ring conductors of

each pair by marking each conductor of a pair with the color of

its mate is permissible. The method of marking shall be accepted

by REA prior to its use.

3.5 Other methods of providing positive identification of the

tip and ring conductors of each pair may be employed if accepted

by REA prior to its use.

3.6 The insulated conductors shall be twisted into pairs.

3.7 In order to provide sufficiently high crosstalk isolation,

the pair twists shall be designed to enable the cable to meet the

capacitance unbalance and the crosstalk loss requirements of

Paragraphs 8.2, 8.3, and 8.4 of this specification.

3.8 The average length of pair twists in any pair in the

finished cable, when measured on any 3 meter (m) (10 foot (ft))

length, shall not exceed 152 mm (6 in.).

4. FORMING OF THE CABLE CORE

4.1 Twisted pairs shall be assembled in such a way as to form a

substantially cylindrical group.

4.2 When desired for lay-up reasons, the basic group may be

divided into two or more subgroups called units.

4.3 Each group, or unit in a particular group, shall be enclosed

in bindings of the colors indicated for its particular pair

count. The pair count, indicated by the color of insulation,

shall be consecutive as indicated in Paragraph 4.5 of this

specification through units in a group.

4.4 Threads or tapes used as binders shall be nonhygroscopic and

nonwicking. The threads shall consist of a suitable number of

ends of each color arranged as color bands. When tapes are used
Bulletin 1753F-207(PE-87)

Page 12

as binders, they shall be colored. Binders shall be applied with

a lay of not more than 100 mm (4 in.). The colored binders shall

be readily recognizable as the basic intended color and shall be

distinguishable from all other colors.

4.5 The colors of the bindings and their significance with

respect to pair count shall be as shown in the following table:

Group No. Color of Bindings Group Pair Count

1 White-Blue 1-25

2 White-Orange 26-50

3 White-Green 51-75

4 White-Brown 76-100

5 White-Slate 101-125

6 Red-Blue 126-150

7 Red-Orange 151-175

8 Red-Green 176-200

9 Red-Brown 201-225

10 Red-Slate 226-250

11 Black-Blue 251-275

12 Black-Orange 276-300

13 Black-Green 301-325

14 Black-Brown 326-350

15 Black-Slate 351-375

16 Yellow-Blue 376-400

17 Yellow-Orange 401-425

18 Yellow-Green 426-450

19 Yellow-Brown 451-475

20 Yellow-Slate 476-500

21 Violet-Blue 501-525

22 Violet-Orange 526-550

23 Violet-Green 551-575

24 Violet-Brown 576-600

4.6 The use of the white unit binder in cables of 100 pair or

less is optional

4.7 When desired for manufacturing reasons, two or more 25 pair

groups may be bound together with nonhygroscopic and nonwicking

threads or tapes into super-units. The group binders and the

super-unit binders shall be colored such that the combination of

the two binders shall positively identify each 25 pair group from

every other 25 pair group in the cable.

4.8 Super-unit binders shall be of the colors shown in the

following table:

Pair No. Binder Color

1-600 White

600-1200 Red
Bulletin 1753F-207(PE-87)

Page 13

5. CORE WRAP

5.1 The core shall be completely covered with a layer of

nonhygroscopic and nonwicking dielectric material. The wrap

shall be applied with an overlap.

5.2 The core wrap shall provide a sufficient heat barrier to

prevent visible evidence of conductor insulation deformation or

adhesion between conductors, caused by adverse heat transfer

during the jacketing operation.

5.3 Engineering Information: If required for manufacturing

reasons, white or uncolored binders of nonhygroscopic and

nonwicking material may be applied over the core and/or core

wrap.

6. SHIELD

6.1 An aluminum shield, plastic coated on one side, shall be

applied longitudinally over the core wrap.

6.2 The shield may be applied over the core wrap with or without

corrugations (smooth) and shall be bonded to the outer jacket.

6.3 The shield overlap shall be a minimum of 3 mm (0.125 in.)

for cables with core diameters of 15 mm (0.625 in.) or less and a

minimum of 6 mm (0.25 in.) for cables with core diameters greater

than 15 mm (0.625 in.). The core diameter is defined as the

diameter under the core wrap and binding.

6.4 General requirements for application of the shielding

material shall be as follows:

6.4.1 Successive lengths of shielding tapes may be joined during

the manufacturing process by means of cold weld, electric weld,

soldering with a nonacid flux, or other acceptable means;

6.4.2 The metal shield with the plastic coating shall have the

coating removed prior to joining the metal ends together. After

joining, the plastic coating shall be restored without voids

using good manufacturing techniques;

6.4.3 The shields of each length of cable shall be tested for

continuity. A one meter (3 ft) section of shield containing a

factory joint shall exhibit not more than 110 percent of the

resistance of a shield of equal length without a joint;

6.4.4 The breaking strength of any section of a shield tape

containing a factory joint shall not be less than 80 percent of

the breaking strength of an adjacent section of the shield of

equal length without a joint;
Bulletin 1753F-207(PE-87)

Page 14

6.4.5 The reduction in thickness of the shielding material due

to the corrugating or application process shall be kept to a

minimum and shall not exceed 10 percent at any spot; and

6.4.6 The shielding material shall be applied in such a manner

as to enable the cable to pass the bend test as specified in

Paragraph 9.1 of this specification.

6.5 The dimensions of the uncoated aluminum tape shall be

0.2030 ± 0.0254 mm (0.0080 ± 0.0010 in.).

6.6 The aluminum tape shall conform to either Alloy AA-1100-0,

AA-1145-0, or AA-1235-0 as covered in the latest edition of

Aluminum Standards and Data, issued by the Aluminum Association,

except that the requirements for tensile strength are waived.

6.7 The singled-sided plastic coated aluminum shield shall

conform to the requirements of ASTM B 736-92a, Type I Coating,

Class 1 or 2, or Type II Coating, Class 1. The minimum thickness

of the Type I Coating shall be 0.038 mm (0.0015 in.). The

minimum thickness of the Type II Coating shall be 0.008 mm

(0.0003 in.).

6.8 The plastic coated aluminum shield shall be tested for

resistance to water migration by immersing a one meter (3 ft)

length of tape under a one meter (3 ft) head of water containing

a soluble dye plus 0.25 percent (%) wetting agent.

6.8.1 After a minimum of 5 minutes, no dye shall appear between

the interface of the shield tape and the plastic coating.

6.8.2 The actual test method shall be acceptable to REA.

6.9 The bond between the plastic coated shield and the jacket

shall conform to the following requirements:

6.9.1 Prepare test strips approximately 200 mm (8 in.) in

length. Slit the jacket and shield longitudinally to produce 4

strips evenly spaced and centered in 4 quadrants on the jacket

circumference. One of the strips shall be centered over the

overlapped edge of the shielding tape. The strips shall be 13 mm

(0.5 in.) wide. For cable diameters less than 19 mm (0.75 in.)

make two strips evenly spaced.

6.9.2 Separate the shield and jacket for a sufficient distance

to allow the shield and jacket to be fitted in the upper and

lower jaws of a tensile machine. Record the maximum force

required to separate the shield and jacket to the nearest newton

(pound-force). Repeat this action for each test strip.
Bulletin 1753F-207(PE-87)

Page 15

6.9.3 The force required to separate the jacket from the shield

shall not be less than 9 N (2 lbf) for any individual strip when

tested in accordance with Paragraph 6.9.2 of this specification.

The average force for all strips of any cable shall not be less

than 18 N (4 lbf).

7. CABLE JACKET AND EXTRANEOUS MATERIAL

7.1 The jacket shall provide the cable with a tough, flexible,

protective covering which can withstand stresses reasonably

expected in normal installation and service.

7.2 The jacket shall be free from holes, splits, blisters, or

other imperfections and shall be as smooth and concentric as is

consistent with the best commercial practice.

7.3 The raw material used for the cable jacket shall be one of

the following four types:

a. Type PVC-55554E0X0 in accordance with

ASTM D 2287-81(1988);

b. Type PVC-65554E0X0 in accordance with

ASTM D 2287-81(1988);

c. Type PVC-55556E0X0 in accordance with

ASTM D 2287-81(1988); or

d. Type PVC-66554E0X0 in accordance with

ASTM D 2287-81(1988).

7.4 The jacketing material removed from or tested on the cable

shall be capable of meeting the following performance

requirements:

Property Jacket Performance

Tensile Strength-Unaged

Minimum, MPa (psi) 13.8 (2,000)

Ultimate Elongation-Unaged

Minimum, Percent (%) 200

Tensile Strength-Aged

Minimum, % of Original 80

Ultimate Elongation-Aged

Minimum, % of Original 50

Impact

Failures, Maximum 2/10
Bulletin 1753F-207(PE-87)

Page 16

7.5 Testing Procedures: The procedures for testing the jacket

samples for compliance with Paragraph 7.4 of this specification

shall be as follows:

7.5.1 Tensile Strength and Ultimate Elongation-Unaged: The test

shall be performed in accordance with ASTM D 2633-82(1989), using

a jaw separation speed of 50 mm/min (2 in./min).

Note: Quality assurance testing at a jaw separation speed

of 500 mm/min (20 in./min) is permissible. Failures at this rate

shall be retested at the 50 mm/min (2 in./min) rate to determine

specification compliance.

7.5.2 Tensile Strength and Ultimate Elongation-Aged: The test

shall be performed in accordance Paragraph 7.5.1 of this

specification after being aged for 7 days at a temperature of

100 ± 1°C in a circulating air oven conforming to ASTM D 2436-85.

7.5.3 Impact: The test shall be performed in accordance with

ASTM D 4565-90a using an impact force of 4 newton-meter

(3 pound force-foot) at a temperature of -10 ± 1°C. The cylinder

shall strike the sample at the shield overlap. A crack or split

in the jacket constitutes failure.

7.6 Jacket Thickness: The nominal jacket thickness shall be as

specified in the following table. The test method used shall be

either the End Sample Method (Paragraph 7.6.1 of this

specification) or the Continuous Uniformity Thickness Gauge

Method (Paragraph 7.6.2 of this specification):

Nominal Jacket Thickness

No. of Pairs mm (in.)

25 or less 1.4 (0.055)

50 1.5 (0.060)

100 1.7 (0.065)

200 1.9 (0.075)

300 2.2 (0.085)

400 2.4 (0.095)

600 2.9 (0.115)

800 and over 3.3 (0.130)

7.6.1 End Sample Method: The jacket shall be capable of meeting

the following requirements:

Minimum Average Thickness 90 % of nominal thickness

Minimum Thickness 70 % of nominal thickness
Bulletin 1753F-207(PE-87)

Page 17

7.6.2 Continuous Uniformity Gauge Method:

7.6.2.1 The jacket shall be capable of meeting the following

requirements:

Minimum Average Thickness 90 % of nominal thickness

Minimum (Min.) Thickness 70 % of nominal thickness

Maximum (Max.) Eccentricity 55 %

Eccentricity = Max. Thickness - Min. Thickness x 100 Percent

Average Thickness

7.6.2.2 Maximum and Minimum Thickness Values: The maximum and

minimum thickness values shall be based on the average of each

axial section.

7.7 The color of the jacket shall be either black or dark grey

in conformance with the Munsell Color System specified in

ASTM D 1535-89.

7.8 There shall be no water or other contaminants in the

finished cable which would have a detrimental effect on its

performance or its useful life.

8. ELECTRICAL REQUIREMENTS

8.1 Mutual Capacitance and Conductance:

8.1.1 The average mutual capacitance (corrected for length) of

all pairs in any reel shall not exceed the following when tested

in accordance with ASTM D 4566-90 at a frequency of 1.0 ± 0.1

kilohertz (kHz) and a temperature of 23 ± 3°C:

Mutual Capacitance

Number of Cable Pairs nanofarad/kilometer (nanofarad/mile)

12 52 ± 4 (83 ± 7)

Over 12 52 ± 2 (83 ± 4)

8.1.2 The root mean square (rms) deviation of the mutual

capacitance of all pairs from the average mutual capacitance of

that reel shall not exceed 3.0 % when calculated in accordance

with ASTM D 4566-90.

8.1.3 The mutual conductance (corrected for length and gauge) of

any pair shall not exceed 3.7 micromhos/kilometer (micromhos/km)

(6.0 micromhos/mile) when tested in accordance with

ASTM D 4566-90 at a frequency of 1.0 ± 0.1 kHz and a temperature

of 23 ± 3°C.
Bulletin 1753F-207(PE-87)

Page 18

8.2 Pair-to-Pair Capacitance Unbalance: The capacitance

unbalance as measured on the completed cable shall not exceed

45.3 picofarad/kilometer (pF/km) (25 picofarad/1000 ft

(pF/1000ft)) rms when tested in accordance with ASTM D 4566-90 at

a frequency of 1.0 ± 0.1 kHz and a temperature of 23 ± 3°C.

8.3 Pair-to-Ground Capacitance Unbalance:

8.3.1 The average capacitance unbalance as measured on the

completed cable shall not exceed 574 pF/km (175 pF/1000 ft) when

tested in accordance with ASTM D 4566-90 at a frequency of

1.0 ± 0.1 kHz and a temperature of 23 ± 3°C.

8.3.2 When measuring pair-to-ground capacitance unbalance all

pairs except the pair under test are grounded to the shield

except when measuring cable containing super-units in which case

all other pairs in the same super-unit shall be grounded to the

shield.

8.3.3 Pair-to-ground capacitance unbalance may vary directly

with the length of the cable.

8.4 Crosstalk Loss:

8.4.1 The rms output-to-output far-end crosstalk loss (FEXT)

measured on the completed cable in accordance with ASTM D 4566-90

at a test frequency of 150 kHz shall not be less than

68 decibel/kilometer (dB/km) (73 decibel/1000 ft (dB/1000 ft)).

The rms calculation shall be based on the combined total of all

adjacent and alternate pair combinations within the same layer

and center to first layer pair combinations.

8.4.2 The FEXT crosstalk loss between any pair combination of a

cable shall not be less than 58 dB/km (63 dB/1000 ft) at a

frequency of 150 kHz . If the loss Ko at a frequency Fo for

length Lo is known, then Kx can be determined for any other

frequency Fx or length Lx by:

Fx Lx

FEXT loss (Kx) = Ko -20 log10  -10 log10 

Fo Lo

8.4.3 The near-end crosstalk loss (NEXT) as measured within and

between units of a completed cable in accordance with

ASTM D 4566-90 at a frequency of 772 kHz shall not be less than

the following mean minus sigma (M-S) crosstalk requirement for

any unit within the cable:

Unit Size M-S decibel (dB)

Within Unit:

12 and 13 Pairs 56
Bulletin 1753F-207(PE-87)

Page 19

18 and 25 Pairs 60

Between Unit:

Adjacent 13 Pairs 65

Adjacent 25 Pairs 66

Nonadjacent (all) 81

Where M-S is the Mean near-end coupling loss based on the

combined total of all pair combinations, less one Standard

Deviation, Sigma, of the mean value.

8.5 Insulation Resistance: Each insulated conductor in each

length of completed cable, when measured with all other insulated

conductors and the shield grounded, shall have an insulation

resistance of not less than 152 megohm-kilometer (500 Megohmmile) at 20 ± 1°C. The measurement shall be made in accordance

with the procedures of ASTM D 4566-90.

8.6 High Voltage Test:

8.6.1 In each length of completed cable, the dielectric strength

of the insulation between conductors shall be tested in

accordance with ASTM D 4566-90 and shall withstand, for 3

seconds, a direct current (dc) potential whose value is not less

than:

a. 3.6 kilovolts for 22-gauge conductors, or

b. 3.0 kilovolts for 24-gauge conductors.

8.6.2 In each length of completed cable, the dielectric strength

between the shield and all conductors in the core shall be tested

in accordance with ASTM D 4566-90 and shall withstand, for

3 seconds, a dc potential whose value is not less than 10

kilovolts.

8.7 Conductor Resistance: The dc resistance of any conductor

shall be measured in the completed cable in accordance with

ASTM D 4566-90 and shall not exceed the following values when

measured at or corrected to a temperature of 20 ± 1°C:

Maximum Resistance

AWG ohms/kilometer (ohms/1000 ft)

22 60.7 (18.5)

24 95.1 (29.0)

8.8 Resistance Unbalance:

8.8.1 The difference in dc resistance between the two conductors

of a pair in the completed cable shall not exceed the values

listed in this paragraph when measured in accordance with the

procedures of ASTM D 4566-90:
Bulletin 1753F-207(PE-87)

Page 20

Resistance Unbalance - Maximum for any Reel

AWG Average Percent Individual Pair Percent

22 1.5 4.0

24 1.5 5.0

8.8.2 The resistance unbalance between tip and ring conductors

shall be random with respect to the direction of unbalance. That

is, the resistance of the tip conductors shall not be

consistently higher with respect to the ring conductors and vice

versa.

8.9 Electrical Variations:

8.9.1 Pairs in each length of cable having either a ground,

cross, short, or open circuit condition shall not be permitted.

8.9.2 The maximum number of pairs in a cable which may vary as

specified in Paragraph 8.9.3 of this specification from the

electrical parameters given in this specification are listed in

this paragraph. These pairs may be excluded from the arithmetic

calculation:

Nominal Maximum Number of Pairs

Pair Count with Allowable Electrical Variation

12-100 1

101-300 2

301-400 3

401-600 4

601 and above 6

8.9.3 Parameter Variations:

8.9.3.1 Capacitance Unbalance-to-Ground: If the cable fails

either the maximum individual pair or average capacitance

unbalance-to-ground requirement and all individual pairs are 3280

pF/km (1000 pF/1000 ft) or less the number of pairs specified in

Paragraph 8.9.2 of this specification may be eliminated from the

average and maximum individual calculations.

8.9.3.2 Resistance Unbalance: Individual pair of not more than

7 percent for all gauges.

8.9.3.3 Far-end Crosstalk Loss: Individual pair combination of

not less than 52 dB/km (57 dB/1000 ft).

Note: REA recognizes that in large pair count cables (600

pair and above) a cross, short, or open circuit condition

occasionally may develop in a pair which does not affect the

performance of the other cable pairs. In theses circumstances

rejection of the entire cable mat be economically unsound or
Bulletin 1753F-207(PE-87)

Page 21

repairs may be impractical. In such circumstances the

manufacturer may desire to negotiate with the customer for

acceptance of the cable. No more than 0.5 percent of the pairs

may be involved.

9. MECHANICAL REQUIREMENTS

9.1 Cable Cold Bend Test: The completed cable shall be capable

of meeting the requirements of ASTM D 4565-90a after conditioning

at -20 ± 2°C except that the mandrel diameters shall be as

specified below:

Cable Outside Diameter Mandrel Diameter

<40 mm (1.5 in.) 15x

>40 mm (1.5 in.) 20x

9.2 Cable Flame Test: The completed cable shall be capable of

meeting a maximum flame height of 3.7 m (12.0 ft) when tested in

accordance with Underwriters Laboratories (UL) 1666 dated

January 22, 1991.

9.3 Cable Listing: All cables manufactured to this specification

at a minimum shall be listed as Communication Riser Cable (Type

CMR) in accordance with Sections 800-50 and 800-51(b) of the 1993

National Electrical Code.

10. SHEATH SLITTING CORD (OPTIONAL)

10.1 Sheath slitting cords may be used in the cable structure at

the option of the manufacturer.

10.2 When a sheath slitting cord is used it shall be nonhygroscopic and nonwicking, continuous throughout a length of

cable, and of sufficient strength to open the sheath without

breaking the cord.

10.3 Sheath slitting cords shall be capable of consistently

slitting the jacket and/or shield for a continuous length of 0.6

m (2 ft) when tested in accordance with the procedure specified

in Appendix B of this specification.

11. IDENTIFICATION MARKER AND LENGTH MARKER

11.1 Each length of cable shall be permanently identified as to

manufacturer and year of manufacture.

11.2 The number of conductor pairs and their gauge size shall be

marked on the jacket.
Bulletin 1753F-207(PE-87)

Page 22

11.3 The marking shall be printed on the jacket at regular

intervals of not more than 1.5 m (5 ft).

11.4 An alternative method of marking may be used if accepted by

REA prior to its use.

11.5 The completed cable shall have sequentially numbered length

markers in FEET OR METERS at regular intervals of not more than

1.5 m (5 ft) along the outside of the jacket.

11.6 The method of length marking shall be such that for any

single length of cable, continuous sequential numbering shall be

employed.

11.7 The numbers shall be dimensioned and spaced to produce good

legibility and shall be approximately 3 mm (0.125 in.) in height.

An occasional illegible marking is permissible if there is a

legible marking located not more than 1.5 m (5 ft) from it.

11.8 The method of marking shall be by means of suitable surface

markings producing a clear, distinguishable, contrasting marking

acceptable to REA. Where direct or transverse printing is

employed, the characters should be indented to produce greater

durability of marking. Any other method of length marking shall

be acceptable to REA as producing a marker suitable for the

field. Size, shape and spacing of numbers, durability, and

overall legibility of the marker will be considered in acceptance

of the method.

11.9 The accuracy of the length marking shall be such that the

actual length of any cable section is never less than the length

indicated by the marking and never more than one percent greater

than the length indicated by the marking.

11.10 The color of the initial marking for a black colored

jacket shall be either white or silver. The color of the initial

marking for a dark grey colored jacket shall be either red or

black. If the initial marking of the black colored jacket fails

to meet the requirements of the preceding paragraphs, it will be

permissible to either remove the defective marking and re-mark

with the white or silver color or leave the defective marking on

the cable and re-mark with yellow. If the initial marking of the

dark grey colored jacket fails to meet the requirements of the

preceding paragraphs, it will be permissible to either remove the

defective marking and re-mark with the red or black color or

leave the defective marking on the cable and re-mark with yellow.

No further re-marking is permitted. Any re-marking shall be on a

different portion of the cable circumference than any existing

marking when possible and have a numbering sequence differing

from any other existing marking by at least 5,000.
Bulletin 1753F-207(PE-87)

Page 23

11.11 Any reel of cable which contains more than one set of

sequential markings shall be labeled to indicate the color and

sequence of marking to be used. The labeling shall be applied to

the reel and also to the cable.

12. PRECONNECTORIZED CABLE (OPTIONAL)

12.1 At the option of the manufacturer and upon request by the

purchaser, cables 100 pairs and larger may be factory terminated

in 25 pair splicing modules.

12.2 The splicing modules shall meet the requirements of REA

Bulletin 345-52, REA Specification for Telephone Splicing

Connectors (Incorporated by Reference at § 1755.97), and be

accepted by REA prior to their use.

13. ACCEPTANCE TESTING AND EXTENT OF TESTING

13.1 The tests described in Appendix A of this specification are

intended for acceptance of cable designs and major modifications

of accepted designs. REA decides what constitutes a major

modification. These tests are intended to show the inherent

capability of the manufacturer to produce cable products having

long life and stability.

13.2 For initial acceptance, the manufacturer shall submit:

a. An original signature certification that the product

fully complies with each section of this specification;

b. Qualification Test Data, per Appendix A of this

specification;

c. To periodic plant inspections;

d. A certification that the product does or does not comply

with the domestic origin manufacturing provisions of the

"Buy American" requirements of the Rural Electrification

Act of 1938 (7 U.S.C. 901 et seq.);

e. Written user testimonials concerning performance of the

product, and;

f. Other nonproprietary data deemed necessary by the Chief,

Outside Plant Branch (Telephone).

13.3 For requalification acceptance, the manufacturer shall

submit an original signature certification that the product fully

complies with each section of the specification, excluding the

Qualification Section, and a certification that the product does

or does not comply with the domestic origin manufacturing
Bulletin 1753F-207(PE-87)

Page 24

provisions of the "Buy American" requirements of the Rural

Electrification Act of 1938 (7 U.S.C. 901 et seq.) for acceptance

by June 30 every three years. The required data and

certification shall have been gathered within 90 days of the

submission.

13.4 Initial and requalification acceptance requests should be

addressed to: Chairman, Technical Standards Committee "A"

(Telephone), Telecommunications Standards Division, Rural

Electrification Administration, Washington, DC 20250-1500.

13.5 Tests on 100 Percent of Completed Cable:

13.5.1 The shield of each length of cable shall be tested for

continuity using the procedures of ASTM D 4566-90.

13.5.2 Dielectric strength between all conductors and the shield

shall be tested to determine freedom from grounds in accordance

with Paragraph 8.6.2 of this specification.

13.5.3 Each conductor in the completed cable shall be tested for

continuity using the procedures of ASTM D 4566-90.

13.5.4 Dielectric strength between conductors shall be tested to

ensure freedom from shorts and crosses in accordance with

Paragraph 8.6.1 of this specification.

13.5.5 Each conductor in the completed preconnectorized cable

shall be tested for continuity.

13.5.6 Each length of completed preconnectorized cable shall be

tested for split pairs.

13.5.7 The average mutual capacitance shall be measured on all

cables. If the average mutual capacitance for the first 100

pairs tested from randomly selected groups is between 50 and 53

nanofarad/kilometer (nF/km) (80 to 85 nanofarad/mile (nF/mile)),

the remainder of the pairs need not be tested on the 100 percent

basis. (See Paragraph 8.1 of this specification).

13.6 Capability Tests: Tests on a quality assurance basis shall

be made as frequently as is required for each manufacturer to

determine and maintain compliance with:

13.6.1 Performance requirements for conductor insulation and

jacket material;

13.6.2 Bonding properties of coated or laminated shielding

materials;

13.6.3 Sequential marking and lettering;

13.6.4 Capacitance unbalance and crosstalk;
Bulletin 1753F-207(PE-87)

Page 25

13.6.5 Insulation resistance;

13.6.6 Conductor resistance and resistance unbalance;

13.6.7 Cable cold bend and cable flame tests; and

13.6.8 Mutual conductance.

14. SUMMARY OF RECORDS OF ELECTRICAL AND PHYSICAL TESTS

14.1 Each manufacturer shall maintain suitable summary of

records for a period of at least 3 years for all electrical and

physical tests required on completed cable by this specification

as set forth in Paragraphs 13.5 and 13.6 of this specification.

The test data for a particular reel shall be in a form that it

may be readily available to the purchaser or to REA upon request.

14.2 Measurements and computed values shall be rounded off to

the number of places of figures specified for the requirement

according to ASTM E 29-90.

15. MANUFACTURING IRREGULARITIES

15.1 Repairs to the shield are not permitted in cable supplied

to the end user under this specification.

15.2 No repairs or defects in the jacket are allowed.

16. PREPARATION FOR SHIPMENT

16.1 The cable shall be shipped on reels unless otherwise

specified or agreed to by the purchaser. The diameter of the

drum shall be large enough to prevent damage to the cable from

reeling or unreeling. The reels shall be substantial and so

constructed as to prevent damage to the cable during shipment and

handling.

16.2 A waterproof corrugated board or other means of protection

acceptable to REA shall be applied to the reel and shall be

suitably secured in place to prevent damage to the cable during

storage and shipment.

16.3 The outer end of the cable shall be securely fastened to

the reel head so as to prevent the cable from becoming loose in

transit. The inner end of the cable shall be securely fastened

in such a way as to make it readily available if required for

electrical testing. Spikes, staples, or other fastening devices

which penetrate the cable jacket shall not be used. The method

of fastening the cable ends shall be accepted by REA prior to it

being used.
Bulletin 1753F-207(PE-87)

Page 26

16.4 Each length of cable shall be wound on a separate reel

unless otherwise specified or agreed to by the purchaser.

16.5 The arbor hole shall admit a spindle 63 mm (2.5 in.) in

diameter without binding. Steel arbor hole liners may be used

but shall be acceptable to REA prior to their use.

16.6 Each reel shall be plainly marked to indicate the direction

in which it should be rolled to prevent loosening of the cable on

the reel.

16.7 Each reel shall be stenciled or labeled on either one or

both sides with the name of the manufacturer, year of

manufacture, actual shipping length, an inner and outer end

sequential length marking, description of the cable, reel number

and the REA cable designation.

CABLE DESIGNATION

CT

Cable Construction

Pair Count

Conductor Gauge

A = Coated Aluminum Shield

P = Preconnectorized Cable

Example: CTAP 100-22

Terminating Cable, Coated Aluminum Shield,

Preconnectorized, 100 pairs, 22 AWG

16.8 When preconnectorized cable is shipped, the splicing

modules shall be protected to prevent damage during shipment and

handling. The protection method shall be acceptable to REA prior

to its use.
Bulletin 1753F-207(PE-87)

Appendix A

Page 27

UNITED STATES DEPARTMENT OF AGRICULTURE

Rural Electrification Administration

APPENDIX A

TERMINATING CABLE

Qualifications Test Methods Bulletin 1753F-207(PE-87)

1. The test procedures described in this appendix are for

qualification of initial designs and major modifications of

"accepted" designs. Included in Paragraph 5 of this appendix are

suggested formats that may be used in submitting test results to

REA.

2. SAMPLE SELECTION AND PREPARATION

2.1 All testing shall be performed on lengths removed

sequentially from the same 25 pair, 22 gauge jacketed cable.

This cable shall not have been exposed to temperatures in excess

of 38°C since its initial cool down after sheathing. The lengths

specified are minimum lengths and if desirable from a laboratory

testing standpoint longer lengths may be used.

2.1.1 Length A shall be 12 ± 0.2 meters (40 ± 0.5 feet) long.

Prepare the test sample by removing the jacket, shield, and core

wrap for a sufficient distance on both ends to allow the

insulated conductors to be flared out. Remove sufficient

conductor insulation so that appropriate electrical test

connections can be made at both ends. Coil the sample with a

diameter of 15 to 20 times its sheath diameter. Two lengths are

required.

2.1.2 Length B shall be 300 millimeters (1 foot) long. Three

lengths are required.

2.1.3 Length C shall be 3 meters (10 feet) long and shall

maintained at 23 ± 3°C for the duration of the test. Two lengths

are required.

2.2 Data Reference Temperature: Unless otherwise specified, all

measurements shall be made at 23 ± 3°C.
Bulletin 1753F-207(PE-87)

Appendix A

Page 28

3. ENVIRONMENTAL TESTS

3.1 Heat Aging Test

3.1.1 Test Samples: Place one sample each of lengths A and B in

an oven or environmental chamber. The ends of sample A shall

exit from the chamber or oven for electrical tests. Securely

seal the oven exit holes.

3.1.2 Sequence of Tests: Sample B referenced in Paragraph 3.1.1

of this appendix shall be subjected to the insulation compression

test outlined in Paragraph 3.2 of this appendix.

3.1.3 Initial Measurements

3.1.3.1 For sample A, measure the open circuit capacitance and

conductance for each odd pair at 1, 150, and 772 kHz after

conditioning the sample at the data reference temperature for 24

hours. Calculate the average and standard deviation for the

data of the 13 pairs on a per kilometer (per mile) basis.

3.1.3.2 Record on suggested formats attached in Paragraph 5 of

this appendix or on other easily readable formats.

3.1.4 Heat Conditioning

3.1.4.1 Immediately after completing the initial measurements,

condition the sample for 14 days at a temperature of 65 ± 2°C.

3.1.4.2 At the end of this period measure and calculate the

parameters given in Paragraph 3.1.3 of this appendix. Record on

suggested formats in Paragraph 5 of this appendix or on other

easily readable formats.

3.1.5 Overall Electrical Deviation

3.1.5.1 Calculate the percent change in all average parameters

between the final parameters after conditioning with the initial

parameters in Paragraph 3.1.3 of this appendix.

3.1.5.2 The stability of the electrical parameters after

completion of this test shall be within the following prescribed

limits:

a. Capacitance: The average mutual capacitance shall be

within 10 percent of its original value;

b. The change in average mutual capacitance shall be less

than 10 percent over the frequency range of 1 to 150

kilohertz; and
Bulletin 1753F-207(PE-87)

Appendix A

Page 29

c. Conductance: The average mutual conductance shall not

exceed 3.7 micromhos/kilometer (6 micromhos/mile) at a

frequency of 1 kilohertz.

3.2 Insulation Compression Test

3.2.1 Test Sample B: Remove jacket, shield, and core wrap being

careful not to damage the conductor insulation. Remove one pair

from the core and carefully separate and straighten the insulated

conductors. Retwist the two insulated conductors together under

sufficient tension to form 10 evenly spaced 360 degree twists in

a length of 100 millimeters (4 inches).

3.2.2 Sample Testing: Center the mid 50 millimeters (2 inches)

of the twisted pair between two smooth rigid parallel metal

plates measuring 50 millimeters (2 inches) in length or diameter.

Apply a 1.5 volt direct current potential between the conductors,

using a light or buzzer to indicate electrical contact between

the conductors. Apply a constant load of 67 newtons

(15 pound-force) on the sample for one minute and monitor for

evidence of contact between the conductors. Record results on

suggested formats attached in Paragraph 5 of this appendix or on

other easily readable formats.

3.3 Temperature Cycling

3.3.1 Repeat Paragraphs 3.1.1 through 3.1.3.2 of this appendix

for separate set of samples A and B which have not been subjected

to prior environmental conditioning.

3.3.2 Immediately after completing the measurements, subject the

test samples to 10 cycles of temperature between -40°C and +60°C.

The test samples shall be held at each temperature extreme for a

minimum of 1.5 hours during each cycle of temperature. The air

within the temperature cycling chamber shall be circulated

throughout the duration of the cycling.

3.3.3 Repeat Paragraphs 3.1.4.2 through 3.2.2 of this appendix.

4. CONTROL SAMPLE

4.1 Test Samples: One length of sample B shall have been

maintained at 23 ± 3°C for at least 48 hours before the testing.

4.2 Repeat Paragraphs 3.2 through 3.2.2 of this appendix.

4.3 Surge Test
Bulletin 1753F-207(PE-87)

Appendix A

Page 30

4.3.1 One length of sample C shall be used to measure the

breakdown between conductors while the other length of C shall be

used to measure core to shield breakdown.

4.3.2 The samples shall be capable of withstanding, without

damage, a single surge voltage of 20 kilovolts peak between

conductors, and 35 kilovolts peak between conductors and the

shield as hereinafter described. The surge voltage shall be

developed from a capacitor discharge through a forming resistor

connected in parallel with the dielectric of the test sample.

The surge generator constants shall be such as to produce a surge

of 1.5 x 40 microseconds wave shape.

4.3.3 The shape of the generated wave shall be determined at a

reduced voltage by connecting an oscilloscope across the forming

resistor with the cable sample connected in parallel with the

forming resistor. The capacitor bank is charged to the test

voltage and then discharged through the forming resistor and test

sample. The test sample will be considered to have passed the

test if there is no distinct change in the wave shape obtained

with the initial reduced voltage compared to that obtained after

the application of the test voltage.

5. TEST DATA FORMATS

5.1 The following suggested formats may be used for submitting

the test data to REA.
Bulletin 1753F-207(PE-87)

Appendix A

Page 31

Environmental Conditioning____________________________

FREQUENCY 1 KILOHERTZ

Pair Capacitance Conductance

Number nF/km (nF/mile) micromhos/km (micromhos/mile)

Initial Final Initial Final

1 _______ _____ _______ _____

3 _______ _____ _______ _____

5 _______ _____ _______ _____

7 _______ _____ _______ _____

9 _______ _____ _______ _____

11 _______ _____ _______ _____

13 _______ _____ _______ _____

15 _______ _____ _______ _____

17 _______ _____ _______ _____

19 _______ _____ _______ _____

21 _______ _____ _______ _____

23 _______ _____ _______ _____

25 _______ _____ _______ _____

 _

Average x _______ _____ _______ _____

Overall Percent

Difference in

 _

Average x _______________ ___________________
Bulletin 1753F-207(PE-87)

Appendix A

Page 32

Environmental Conditioning____________________________

FREQUENCY 150 KILOHERTZ

Pair Capacitance Conductance

Number nF/km (nF/mile) micromhos/km (micromhos/mile)

Initial Final Initial Final

1 _______ _____ _______ _____

3 _______ _____ _______ _____

5 _______ _____ _______ _____

7 _______ _____ _______ _____

9 _______ _____ _______ _____

11 _______ _____ _______ _____

13 _______ _____ _______ _____

15 _______ _____ _______ _____

17 _______ _____ _______ _____

19 _______ _____ _______ _____

21 _______ _____ _______ _____

23 _______ _____ _______ _____

25 _______ _____ _______ _____

 _

Average x _______ _____ _______ _____

Overall Percent

Difference in

 _

Average x _______________ ___________________
Bulletin 1753F-207(PE-87)

Appendix A

Page 33

Environmental Conditioning____________________________

FREQUENCY 772 KILOHERTZ

Pair Capacitance Conductance

Number nF/km (nF/mile) micromhos/km (micromhos/mile)

Initial Final Initial Final

1 _______ _____ _______ _____

3 _______ _____ _______ _____

5 _______ _____ _______ _____

7 _______ _____ _______ _____

9 _______ _____ _______ _____

11 _______ _____ _______ _____

13 _______ _____ _______ _____

15 _______ _____ _______ _____

17 _______ _____ _______ _____

19 _______ _____ _______ _____

21 _______ _____ _______ _____

23 _______ _____ _______ _____

25 _______ _____ _______ _____

 _

Average x _______ _____ _______ _____

Overall Percent

Difference in

 _

Average x _______________ ___________________
Bulletin 1753F-207(PE-87)

Appendix A

Page 34

INSULATION COMPRESSION

 Failures

 Control ________

 Heat Age ________

 Temperature Cycling ________

SURGE TEST (kilovolts)

 Conductor to Conductor ______________

 Shield to Conductors ______________
 Bulletin 1753F-207(PE-87)

 Appendix B

 Page 35

UNITED STATED DEPARTMENT OF AGRICULTURE

Rural Electrification Administration

APPENDIX B

Sheath Slitting Cord Qualification

1. This test procedure described in this appendix is for

qualification of initial and subsequent changes in sheath

slitting cords.

2. SAMPLE SELECTION: All testing shall be performed on two

1.2 m (4 ft) length of cable removed sequentially from the same

25 pair, 22 gauge jacketed cable. This cable shall not have been

exposed to temperatures in excess of 38°C since its initial cool

down after sheathing.

3. TEST PROCEDURE

3.1 Using a suitable tool, expose enough of sheath slitting cord

to permit grasping with needle nose pliers.

3.2 The prepared test specimens shall be maintained at a

temperature of 23 ± 1°C for at least 4 hours immediately prior to

and during the test.

3.3 Wrap the sheath slitting cord around the plier jaws to

ensure a good grip.

3.4 Grasp and hold the cable in a convenient position while

gently and firmly pulling the sheath slitting cord longitudinally

in the direction away from the cable end. The angle of pull may

vary to any convenient and functional degree. A small starting

notch is permissible.

3.5 The sheath slitting cord is considered acceptable if the

cord can slit the jacket and/or shield for a continuous length

of 0.6 m (2 ft) without breaking the cord.