Application
Changing to high temperature conductors (Hot and Black conductors) has approved as an excellent technical and economical solution for revitalisation of old overhead lines or for bottleneck applications.
Product Description Hot Conductors
Starting from high grade aluminium (99,7 % purity) an alloy containing, among other elements, small amounts of zirconium is produced. With additional processing, a structure with a high recrystallization temperature is attained, thereby the mechanical properties of this material are maintained in continuous operation at higher temperatures (150 °C). In this way the current carrying capacity could be increased by over 50%.
Because of the combination of temperature resistant aluminium (TAL) and aluminium clad steel wires (ACS) the stranding can be done without grease. The mechanical properties of the temperature resistant aluminium (TAL) wires correspond to those of pure aluminium (99,5%)
Product Description Black Conductors
Coated hot conductors are a further development. These are blackened by a patented spray process with a permanent layer of black polyurethane coating on their surface. The black surface means a higher radiation of temperature, so the current carrying capacity could be increased by up to 70% in total.
The coating of the conductors fulfils all requirements:
Mechanical and Electrical Properties
Due to the higher temperature tolerance of the conductors up to 150 °C more energy can be transmitted compared to standard aluminium steel conductors (ACSR) of the same section.
This advantage is achieved by the special properties of the temperature resistant aluminium (TAL) wire:
conductivity [S*m/mm²] | min. tensile strength [N/mm²] | modulus of elasticity [N/mm²] | coefficient of expansion [1/°C] | permissible maximum operating temperature [°C] | |||
continuous operation | short-time < 30 min | short-circuit | |||||
TAL | 34,8 | 160 - 190 | 60.000 | 2,3 * 10E-5 | 150 | 180 | 260 |
E-AL | 35,38 | 160 - 190 | 60.000 | 2,3 * 10E-5 | 80 | 80 | 160 |
Using black conductors (BTAL/ACS) increases the transmission power additionally. The comparison of several sections shows this advantage:
nominal section [mm²] | linear weight [kg/km] | calculated tensile strength [kN] | resistivity at 20 °C [Ω/km] | permissible continuous current [A] | |||||
ACSR | TAL/ACS | ACSR | TAL/ACS | ACSR | TAL/ACS | ACSR | TAL/ACS | BTAL/ACS | |
120/20 | 491 | 467 | 44,50 | 45,09 | 0,2376 | 0,2286 | 410 | 645 | 690 |
240/40 | 980 | 932 | 85,12 | 87,49 | 0,1188 | 0,1144 | 640 | 1010 | 1090 |
300/50 | 1227 | 1167 | 105,09 | 108,06 | 0,0949 | 0,0914 | 740 | 1170 | 1270 |
560/50 | 1940 | 1879 | 146,28 | 149,25 | 0,0515 | 0,0508 | 1040 | 1715 | 1870 |
*) | AL/St = ACSR | = aluminium/steel (standard conductor) |
TAL/ACS | = temperature resistant aluminium/ACS (Hot Conductor) | |
BTAL/ACS | = temperature resistant aluminium/ACS, black coating (Black Conductor) |