Question

What is the size of transmission lines?

Answer 1

The size of transmission lines varies depending on the voltage level, power capacity, and distance of transmission. Transmission lines are classified into different voltage levels, and their conductor sizes increase with higher voltage ratings.

### **Common Transmission Line Sizes**
1. **Low Voltage (LV) Transmission Lines** (up to 1 kV)  
   - Used for local distribution.
   - Typical conductor size: **10 mm² to 50 mm²** (Copper or Aluminum).

2. **Medium Voltage (MV) Transmission Lines** (1 kV – 69 kV)  
   - Used for regional distribution.
   - Conductor size: **50 mm² to 300 mm²**.

3. **High Voltage (HV) Transmission Lines** (69 kV – 220 kV)  
   - Used for long-distance power transmission.
   - Conductor size: **300 mm² to 800 mm²**.

4. **Extra High Voltage (EHV) Transmission Lines** (220 kV – 765 kV)  
   - Used for inter-city and interstate power transmission.
   - Conductor size: **800 mm² to 1600 mm²**.

5. **Ultra High Voltage (UHV) Transmission Lines** (Above 765 kV)  
   - Used for massive power transmission across large distances.
   - Conductor size: **1000 mm² to 2500 mm²**.

### **Common Conductors Used**
- **ACSR (Aluminum Conductor Steel Reinforced)** – Used for long-distance transmission due to strength and conductivity.
- **AAC (All Aluminum Conductor)** – Used for short spans in urban areas.
- **AAAC (All Aluminum Alloy Conductor)** – Lighter and corrosion-resistant.
- **Copper Conductors** – Rarely used in high-voltage lines due to cost.

Would you like more details on conductor selection for a specific application?