 Air Core Cables to GR-421_clip_image002.jpg)
Applicazione
The cables are designed for use as subscriber distribution cables and as connection between central offices. The cables are suitable for installation in ducts, direct burial in the ground and also for aerial installation with integral suspension strand. An armoured option is offered for direct burial installations. A figure-8 self support option is offered for aerial installation.
Norme
 Air Core Cables to GR-421_clip_image002.gif)
• Telcordia (Bellcore) GR-421
Costruzione
Conduttori
Solid annealed bare copper, 0.4/0.5/0.63/0.9mm, as per ASTM B-3/class 1 of IEC 60228
Isolamento
Solid medium or high density polyethylene as per ASTM D 1248/IEC 60708
Coppie intrecciate
Insulated conductors are twisted into pairs with varying lay length to minimize crosstalk
Elemento di cablaggio
Twisted Pairs
Cavo Core Assemblea
Cables with up to 400 pairs are composed of 25-pair units or 12/13-pair units; cables with over 400 pairs are composed of 50 or 100-pair units. Any extra pairs form a separate unit. Units are identified by colour coded binders. Construction is per GR-421 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
Umidità Barriera
A layer of 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. In cables with more than 200 pairs, the aluminum tape may be corrugated for improved cable flexibility
Guaina
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
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
Filo di continuità (optional)
One tinned copper drain wire may be longitudinally laid to ensure electrical continuity of the screen
Optional Construction
Cavo armato
0.15mm thick corrugated steel tape armour is applied with an overlap over an optional inner polye-thylene sheath. An outer polyethylene sheath is applied over the armour
Self-Support Cavi
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
 Air Core Cables to GR-421_clip_image002_0000.gif)
Aabbreviations
LAP (CAP):Copolymer coated aluminium tape + PE sheath
LAPSP (CAPSP):LAP sheath + steel tape armour + PE sheath
AP (ALPETH): Bare aluminium tape + PE sheath
PAP:
PE inner sheath + bare aluminium tape + PE sheath
PASP:
PE inner sheath + bare aluminium tape + steel tape armour + PE outer sheath
ASP (STAPETH):
Bare aluminium tape + steel tape armour + PE outer sheath
CACSP: Copolymer coated aluminum tape + copolymer coated steel tape armour + PE outer sheath
LAPSP:
Copolymer coated aluminum tape +PE inner sheath + steel tape armour + PE outer sheath
FIGURE 8 LAP:
Copolymer coated aluminum tape + PE outer sheath + self supporting
Proprietà elettriche
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 Conductor (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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