AVOCAB is one of the largest manufacturer of variety of cables and an established name in India as well as abroad. AVOCAB Wires and Cables are most preferred with numerous installations throughout the country. The range of products includes Power Cables, High tension cables XLPE , LT XLPE And PVC Cables, Instrumentation Cables, House wires and Flexibles. AVOCAB High Tension Cables up to 66 KV are manufactured at its modern manufacturing set up at Chattral. Technological up gradation and Polymer revolution has Replaced the conventional paper insulated cables and thermoplastic insulated cables with cross linked Polyethelene (XLPE) having Better electrical, mechanical and thermal properties with reduced cable weight and dimensions. Worldwide acceptable trends are adopted by AVOCAB’S aim is to manufacture cables of highest quality and to provide customer satisfaction that is unparalleled in the industry.
SIZE
Flame Retardant (FR), Flame Retardant Low Smoke (FRLS) and Flame Retardant Zero Halogen (FRZH) Sheathed HT XLPE cables are also manufactured.
The High Tension cables are manufactured on sophisticated triple Extrusion line, in highly quality conscious environment with Testing and Inspection from raw material to finished cables. The assurance of quality is further ensured by ISI certification on cables.
Nominal area Of conductor ( sq.mm) |
P. V .C Cable | XLPE Cable | ||
Single phase | Three phase | Single phase | Three phase | |
1.5 | 43.44 | 37.62 | 46.34 | 40.13 |
2.5 | 29.04 | 25.15 | 30.98 | 26.83 |
4 | 17.78 | 15.40 | 18.98 | 16.44 |
6 | 11.06 | 9.58 | 11.80 | 10.22 |
10 | 7.40 | 6.41 | 7.88 | 6.82 |
16 | 4.58 | 3.97 | 4.90 | 4.24 |
25 | 2.89 | 2.50 | 3.08 | 2.67 |
35 | 2.10 | 1.80 | 2.23 | 1.94 |
50 | 1.55 | 1.30 | 1.65 | 1.44 |
70 | 1.10 | 0.94 | 1.15 | 1.00 |
95 | 0.79 |
The conductor size in the cables for any installation is also governed by its ability to carry short circuit current of system. For L.V Distribution cable may be selected on the basis of continuous load current. But in case of MV /HV distribution it is always safer to select the cable on the basis of ability of conductor to carry expected short circuit current. Short circuit current rating of cable should in line with short circuit capacity of demanding apparatus such as circuit breakers, Transformer & Reactor etc. beside its capacity to carry desired load current . Short circuits rating of cables each size are given in relevant tables & have been calculated on the basis of IEC -949 & IEC -986 & on the following assumption
A) Temperature of conductor just prior to short circuit
B) Maximum permissible conductor temperature during short circuit
C) Volumetric specified heat of the conductor
D) Reciprocal of temperature co –efficient of resistance of resistance at 9 Deg. C
Short Circuit current rating at different duration may be calculated as
Nominal area of conductor | PVC CABLE | XLPE CABLE | ||
Single phase | Three phase | Single phase | Three phase | |
120 | 0.63 | 0.55 | 0.66 | 0.56 |
150 | 0.52 | 0.46 | 0.55 | 0.48 |
185 | 0.42 | 0.37 | 0.44 | 0.40 |
240 | 0.34 | 0.30 | 0.35 | 0.30 |
300 | 0.28 | 0.26 | 0.30 | 0.26 |
400 | 0.24 | 0.22 | 0.24 | 0.22 |
500 | 0.23 | 0.20 | 0.23 | 0.20 |
630 | 0.20 | 0.18 | 0.21 | 0.18 |
800 | 0.90 | – | 0.20 | – |
1000 | 0.18 | – | 0.18 | – |
REQUIRED DATAS |
FOR EXAMPLE | |
1 | Nominal system voltage at H.T.side | 11 KV |
2 | Short Circuit level for H.T. system | 2.5 KA |
3 | Fault withstands time for H.T. CBs | 0.5 Sec |
4 | Formula for calculating H.T. cable size |