Telephone Cables

 Foam Skin Insulated & AP Sheathed (ALPETH) Jelly Filled Cables to ICEA S-84-608

Application

The cables are designed for use in access or trunk networks, from telephone exchange to subscriber area. The cables are suitable for installation in ducts, direct burial in the ground and also for aerial installation with integral suspension strand.Jelly filled option is for subscriber’s cables installed underground or along the edge of pavement. An armoured option is offered for direct burial installations where additional mechanical or rodent protection is required. A figure-8 self support option is offered for aerial installation.

Standards

• ANSI/ICEA S-84-608

 

 

 

Construction

Conductors
Solid annealed bare copper, 0.4/0.5/0.63/0.9mm as per ASTM B-3/class 1 of IEC 60228

Insulation
Foam skin which is a composite polyethylene insulation made of an inner cellular layer and an outer solid skin as per ASTM D 1248/IEC 60708

Twisted Pairs
Insulated conductors are twisted into pairs with varying lay length to minimize crosstalk

Cabling Element
Twisted Pairs

Cable Core Assembly
Cables of 25 pairs or less are assembled into cylindrical core. Cables larger than 25 pairs are assembled into units, which are then used to form the core. Units are identified by colour coded binders. Standard construction is per ICEA S-84-608 given in Cable Make Up Diagram

Core Wrapping
One or more non-hygroscopic polyester tapes are helically or longitudinally laid with an overlap. These tapes furnish thermal, mechanical as well as high dielectric protection between shielding and individual conductors

Moisture Barrier
A layer of corrugated bare aluminium tape (0.2mm/8mil) is applied longitudinally with overlap over the cable core to provide 100% electrical shielding coverage and ensures a barrier against water vapor

Filling
The cable core interstices are filled with petroleum jelly to avoid longitudinal water penetration within the cable.
The water resistant filling compound is applied to the air space between non-hygroscopic tape and shield, shield and sheath within the cable core

Sheath
Black low density polyethylene as per ASTM D 1248/IEC 60708, being able to withstand exposure to sunlight,
temperature variations, ground chemicals and other environmental contaminants

Ripcord(optional)
Ripcord may be provided for slitting the sheath longitudinally to facilitate its removal

Spare Pairs (optional)
Spare pairs may be incorporated for large pair cables

Continuity Wire (optional)
One tinned copper drain wire may be longitudinally laid to ensure electrical continuity of the screen

 

 

 

 

 

Optional Construction

Armoured Cable
0.15mm/6mil thick corrugated steel tape armour is applied with an overlap over an optional inner polyethylene sheath. An outer polyethylene sheath is applied over the armour

Self-Support Cables
A 7-strand galvanized steel strand is used as support wire. Black polyethylene sheath covers both core and support wire in a figure-8 construction

Shield Options
There are 8 different shield options which can be offered in this standard:
1) 8 mil bare aluminium tape
2) 8 mil coated aluminium tape
3) 5 mil copper tape
4) 5 mil copper clad alloy steel tape
5) 5 mil copper clad stainless steel tape
6) 6 mil & 7 mil 194 copper alloy tape
7) 6 mil bare steel tape
8) 6 mil coated steel tape

Electrical Properties

Nominal Conductor Diameter

mm

0.4

0.5

0.63

0.9

Conductor Gauge Size

AWG

26

24

22

19

Maximum Average DC Resistance

Ω/km / Ω/mile

140/225

87/140

55/88.6

27.0/43.4

Maximum Individual DC Resistance

Ω/km / Ω/mile

144.2/232

89.5/144

56.5/91.0

28.0/45.0

Minimum Insulation Resistance @500V DC

MΩ.km / MΩ.mile

1600/1000

1600/1000

1600/1000

1600/1000

Maximum Average Resistance Unbalance

%

1.5

1.5

1.5

1.5

Maximum Individual Resistance Unbalance

%

5

5

5

5

Average Mutual Capacitance nF/km / nF/kft 48.5-54.0
/14.8-16.5
48.5-54.0
/14.8-16.5
48.5-54.0
/14.8-16.5
48.5-54.0
/14.8-16.5
Maximum Individual Mutual Capacitance nF/km / nF/kft 57/17.4 57/17.4 57/17.4 57/17.4
Maximum Individual Capacitance Unbalance pair-to-pair pF/km / pF/kft 145/44 145/44 145/44 145/44
Capacitance Unbalance RMS pair-to-pair pF/km / pF/kft 45/13.7 45/13.7 45/13.7 45/13.7
Maximum Individual Capacitance Unbalance
pair-to-ground
pF/km / pF/kft 2625/800 2625/800 2625/800 2625/800
Maximum Average Capacitance Unbalance
pair-to-ground
pF/km / pF/kft 574/175 574/175 574/175 574/175
Maximum Conductor Loop Resistance @20°C Ω/km / Ω/mile 300/482 192/309 114/183.6 60/96.4
Impedance @1KHz Ω 994 796 660 445
Impedance @100KHz Ω 147 134 125 122
Impedance @512KHz Ω 120 118 117 116
Impedance @1MHz Ω 117 115 114

113

Maximum Average Attenuation @0.8KHz

dB/km / dB/kft

1.64/0.5

1.30/0.39

1.04/0.32

0.74/0.22

Maximum Average Attenuation @1KHz

dB/km / dB/kft

1.68/0.51

1.35/0.41

1.08/0.33

0.76/0.23

Maximum Average Attenuation @3KHz

dB/km / dB/kft

3.18/0.97

2.52/0.77

2.01/0.61

1.42/0.43

Maximum Average Attenuation @150KHz

dB/km / dB/kft

11.4/3.47

8.3/2.53

6.2/1.89

4.4/1.34

Maximum Average Attenuation @772KHz

dB/km / dB/kft

24.3/7.4

19.4/5.9

15.4/4.7

10.8/3.3

Maximum Average Attenuation @1000KHz

dB/km / dB/kft

27.1/8.25

21.4/6.52

17.5/5.33

12.8/3.89

Dielectric Strength          
Conductor to Conductor (3secs) V DC

2400

3000

4000

5000

Conductor to Screen (3secs) V DC

10000

10000

10000

10000

Minimum EL Far-end Cross-talk-Mean Power Sum          

           @150KHz

dB/305m / dB/kft

61

63

63

65

           @772KHz

dB/305m / dB/kft

47

49

49

57

           @1.6MHz

dB/305m / dB/kft

41

42

43

44

           @3.15MHz

dB/305m / dB/kft

35

37

37

39

           @6.3MHz

dB/305m / dB/kft

29

31

31

33

Minimum Far-end Cross-talk-Worst Pair Power Sum          

           @150KHz

dB/305m / dB/kft

57

57

57

59

           @772KHz

dB/305m / dB/kft

43

43

43

45

           @1.6MHz

dB/305m / dB/kft

37

37

37

39

           @3.15MHz

dB/305m / dB/kft

31

31

31

33

           @6.3MHz

dB/305m / dB/kft

25

25

25

27

Minimum Near-end Cross-talk-Mean Power Sum          

           @150KHz

dB/305m / dB/kft

58

58

58

58

           @772KHz

dB/305m / dB/kft

47

47

47

47

           @1.6MHz

dB/305m / dB/kft

43

43

43

43

           @3.15MHz

dB/305m / dB/kft

38

38

38

38

           @6.3MHz

dB/305m / dB/kft

34

34

34

34

Minimum Near-end Cross-talk-Worst Pair Power Sum          

           @150KHz

dB/305m / dB/kft

53

53

53

53

           @772KHz

dB/305m / dB/kft

42

42

42

42

           @1.6MHz

dB/305m / dB/kft

38

38

38

38

           @3.15MHz

dB/305m / dB/kft

33

33

33

33

           @6.3MHz

dB/305m / dB/kft

29

29

29

29

Nominal Insulation Thickness

mm

0.175

0.2

0.26

0.3

Nominal Insulated Conductor Diameter

mm

0.75

0.9

1.15

1.5

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