1. YJV Cable Models and Specifications
YJV cable cores mainly include single-core, 2-core, 3-core, 4-core, 5-core, 3+1, 3+2, and 4+1. 3+1 represents 3 phase conductors + 1 ground conductor, 3+2 represents 3 phase conductors + 2 ground conductors, and 4+1 represents 4 phase conductors + 1 ground conductor.
Based on the standard model, specific sizes include: 1 square, 1.5 square, 2.5 square, 4 square, 6 square, 10 square, 16 square, 25 square, 35 square, 50 square, 70 square, 95 square, 120 square, 150 square, 185 square, 240 square, and 300 square. For example, a YJV 3*185+2*95 cable consists of three 185 square phase conductors and two 95 square ground conductors. Since the phase and ground conductor combinations are standardized, the 95 square at the end of the YJV 3*185+2*95 cable can be omitted.
YJV cables range in size from 1 square to 240 square (customization is also possible). They are used for transmitting and distributing electrical energy. They are most commonly used in urban underground power grids, outbound lines for power stations, internal power supplies for industrial and mining enterprises, and underwater transmission lines across rivers and seas. The proportion of cables in power lines is increasing. Power cables are used to transmit and distribute high-power electrical energy within the main lines of power systems. These cables include power cables with voltages ranging from 1 to 500 kV and above, and with various insulation levels.
2. Cable model numbers consist of eight components:
1) Application code - not marked as power cable, K for control cable, P for signal cable;
2) Insulation code - Z for oil-impregnated paper, X for rubber, V for polyvinyl chloride, YJ for cross-linked polyethylene
3) Conductor material code - not marked as copper, L for aluminum;
4) Sheath code - Q for lead sheath, L for aluminum sheath, H for rubber sheath, V for polyvinyl chloride sheath
5) Derivative code - D for non-drip, P for dry insulation;
6) Outer sheath code
7) Special product code - TH for wet tropical zone, TA for dry tropical zone;
8) Rated voltage - in kV
YJV is a cross-linked polyethylene insulated and polyvinyl chloride sheathed cable.
3. Structure of YJV Cables
YJV cables are categorized from the inside out as follows: core, conductor insulation, filler layer, shield, steel tape armor, and sheath.
Among them, the wire core of YJV is mainly copper core, and aluminum core is less used; the conductor insulation layer is polyvinyl chloride insulation; the filling layer is made of softer nylon material to fill the gaps between the wire cores and protect the wire cores at the same time; generally, power cables of 15KV and above generally have conductor shielding layer and insulation shielding layer; steel belt armor is a steel protective layer wrapped around the outside of the wire core, which prevents the cable from being squeezed and deformed. Armored YJV cable is mostly used for underground burial; the sheath layer is the outermost layer of the YJV cable, made of polyethylene, which plays the role of insulation and protection.
