OVERHEAD LINES FOR HIGH AND MEDIUM VOLTAGE
ENEL/ TERNA’S ALUMINIUM (AAC) AND ALUMINIUM STEEL (A.C.S.R.) CONDUCTORS
Aluminium conductors ( AAC) and Aluminium Steel conductors (A.C.S.R.) are widely used in high and medium voltage for electricity transmission and distribution networks, in accordance with the technical specifications of ENEL and TERNA
1. AAC conductors (All Aluminium Conductor)
AAC conductors consist of high-conductivity hard aluminum wires (typically 1350-H19 alloy) twisted together to form a strand. These conductors are characterized by:
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High electrical conductivity
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Good corrosion resistance, ideal in coastal or industrial environments
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Lightweight, makes the installation easier
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Low mechanical strength, which limits its use to short spans or urban networks
Gli AAC vengono usati principalmente nelle reti di distribuzione urbana aerea, dove i carichi meccanici non sono elevati e si richiede una buona capacità di conduzione.
2. ACSR conductors (Aluminium Conductor Steel Reinforced)
ACSR conductors are made of one or more layers of aluminium wires arranged around a central galvanized steel core. The steel core provides the conductor with:
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High mechanical resistance, suitable for long spans and installations in harsh environmental conditions
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Greater tensioning capacity, useful in high-voltage transmission lines
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Good electrical conductivity, thanks to the aluminum outer layer
ACSRs are primarily used in national and interregional transmission grids (high and extra-high voltage), in accordance with TERNA’s standards and specifications. The number of aluminum strands and the percentage of steel vary depending on the mechanical and electrical requirements of the route.
3. Regulations and Technical Specifications
ENEL and TERNA adopt specific standards for the design and supply of conductors:
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CEI and UNI EN standards for dimensional, mechanical, and performance characteristics
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ENEL Technical Specifications (ST) and TERNA Specifications for coding, identification and testing.
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Permanent marking for traceability and compliance with operational requirements
4. Typical Applications
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AAC: Overhead lines for Medium and low voltage, Urban areas, connections in corrosive environments
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ACSR: HV and EHV transmission lines, special crossings, and high-stress mechanical systems
| CATEGORY/ PROGRESSIVE | DIAMETER MM | FORMATION | DESCRIPTION | SECTION | WEIGHT | LENGHT | ||
|---|---|---|---|---|---|---|---|---|
 |  | 1009897 | 10,7 | 19X2.14 | Aluminium alloy conductor for high speed contact line | 68,34 mmq. | 1.878 Kg/Km | |
 |  | 1009903 | 13,32 | (26X2.10)+(7X1.64) | Aluminium/steel bi-metallic conductor for primary lines | 100,00 mmq. | 3.688 Kg/Km | |
 |  | 1009898 | 15,85 | (26X2.50)+(7X1.95) | Aluminium alloy conductor for high speed contact line | 148,50 mmq. | 5.162 Kg/Km | drums of 2.000 mt |
 |  | 1009919 | 17,1 | (26X2.70)+(7X2.10) | Aluminium/ steel bi-metallic conductor for primary lines | 173,00 mmq. | 5.760 Kg/Km | |
 |  | 1009928 | 17,5 | (30X2.50)+(7X2.50) | Aluminium alloy conductor for high speed contact line | 181,62 mmq. | 6.830 Kg/Km | drums of 2.000 mt |
 |  | 1009907 | 17,74 | (26X2.80)+(7X2.18) | Aluminium/ steel bi-metallic conductor for primary lines | 186,20 mmq. | 6.540 Kg/Km | |
 |  | 1009925 | 18,9 | (54X2.10)+(7X2.10) | Aluminium alloy conductor for high speed contact line | 211,90 mmq. | 7.940 Kg/Km | |
 |  | 1009926 | 19,02 | (26X3.00)+(7X2.34) | Aluminium/ steel bi-metallic conductor for primary lines | 213,88 mmq. | 7.430 Kg/Km | drums of 2.000 mt |
 |  | 1009927 | 19,38 | (26X3.06)+(7X2.38) | Aluminium/ steel bi-metallic conductor for primary lines | 222,35 mmq. | 7.720 Kg/Km | drums of 2.000 mt |
 |  | 1009909 | 19,6 | (30X2.80)+(7X2.80) | Aluminium/ steel bi-metallic conductor for primary lines | 227,83 mmq. | 8.480 Kg/Km | drums of 2.000 mt |
 |  | 1009908 | 21 | (30X3.00)+(7X3.00) | Aluminium/ steel bi-metallic conductor for primary lines | 261,50 mmq. | 9.850 Kg/Km | |
 |  | 0 | 22,5 | (54X3.50)+(7X2.50) | Aluminium/ steel bi-metallic conductor for primary lines | 299,28 mmq. | 1.005 Kg/Km | |
 |  | 1004200 | 22,8 | (26X3.60)+(7X2.80) | Aluminium/ steel bi-metallic conductor for primary lines | 307,70 mmq. | 1.068 Kg/Km | drums of 2.000 mt |
 |  | 0 | 24,84 | (54X2.76)+(7X2.76) | Aluminium/ steel bi-metallic conductor for primary lines | 364,95 mmq. | 1.221 Kg/Km | drums of 2.000 mt |
 |  | 1009905 | 26,9 | (30X3.85)+(19X2.30) | Aluminium/ steel bi-metallic conductor for primary lines | 428,20 mmq. | 1.586 Kg/Km | drums of 2.000 mt |
 |  | 1009936 | 27 | (54X3.00)+(7X3.00) | Aluminium/ steel bi-metallic conductor for primary lines | 431,18 mmq. | 1.490 Kg/Km | drums of 2.000 mt |
 |  | 1009913 | 29,3 | (30X4.20)+(19X2.50) | Aluminium/ steel bi-metallic conductor for primary lines | 508,90 mmq. | 1.906 Kg/Km | |
 |  | 1004201 | 31,5 | (54X3.50)+(19X2.10) | Aluminium/ steel bi-metallic conductor for primary lines | 585,30 mmq. | 1.953 Kg/Km | drums of 2.000 mt |
 |  | 1004202 | 34,6 | (54X3.80)+(19X2.30) | Aluminium/ steel bi-metallic conductor for primary lines | 707,58 mmq. | 2.358 Kg/Km | drums of 2.000 mt |
 |  | 314210 | 36 | 61X4 | Aluminium/ steel bi-metallic conductor for primary lines | 766,50 mmq. | 2.118 Kg/Km | drums of 2.000 mt |
 |  | 1004203 | 40,5 | (54X4.50)+(19X2.70) | Aluminium/ steel bi-metallic conductor for primary lines | 967,60 mmq. | 3.230 Kg/Km | drums of 2.000 mt |
 |  | 1011960 | 41,1 | 91x3.74 | Aluminium/ steel bi-metallic conductor for primary lines | 999,70 mmq. | 2.770 Kg/Km | drums of 2.000 mt |
ENEL/TERNA’S ALUMINIUM ALLOYS CONDUCTORS (AAAC)
| CATEGORY / PROGRESSIVE | DIAMETER MM | FORMATION | DESCRIPTION | SECTION | WEIGHT | LENGHT | ||
|---|---|---|---|---|---|---|---|---|
 |  | 315204 | 10,7 | 19X2.14 | Aluminium alloy conductor | 68,34 mmq. | 1.878 Kg/Km | drums of 2.000 mt |
 |  | 26,9 | (30X3.85)+(19X2.30) | Aluminium alloy conductor | 428,19 mmq. | 1.607 Kg/Km | drums of 2.000 mt | |
 |  | 317121 | 31,5 | (54X3.50)+(19X2.10) | Aluminium alloy conductor | 585,30 mmq. | 1.951 Kg/Km | drums of 2.000 mt |