Question

Draw the symbols and state their function of components used in substation (any six).

Answer 1

Certainly! Substations are crucial in electrical power systems, as they help in transforming voltage levels and managing the flow of electricity. Here are six key components used in substations, including their symbols and functions:

### 1. **Circuit Breaker**

**Symbol:**
```
  ____
 |    |
 |____|
```

**Function:**
A circuit breaker is a protective device that automatically switches off the electrical circuit when a fault is detected, such as an overload or short circuit. This prevents damage to the electrical system and ensures safety.

### 2. **Transformer**

**Symbol:**
```
  ___
 |___|
 |___|
```

**Function:**
A transformer is used to change the voltage level of electricity. It steps up (increases) or steps down (decreases) the voltage according to the needs of the power system. This adjustment helps in efficient power transmission and distribution.

### 3. **Busbar**

**Symbol:**
```
 ____
|    |
|____|
```

**Function:**
A busbar is a conductive material that serves as a common connection point for multiple circuits. It distributes electrical power to different outgoing feeders or equipment, allowing for efficient and organized distribution.

### 4. **Disconnect Switch (Isolator)**

**Symbol:**
```
  _____
 |     |
 |_____|_____
           |
           |
```

**Function:**
A disconnect switch, or isolator, is used to isolate a section of the electrical system for maintenance or emergency purposes. It ensures that no electrical current flows through the section, providing safety for maintenance personnel.

### 5. **Current Transformer (CT)**

**Symbol:**
```
 ____
|    |
|____|
   |
   |
```

**Function:**
A current transformer is used to measure the current flowing through a circuit. It provides a scaled-down current proportional to the actual current, which is then used by protection devices and metering equipment.

### 6. **Voltage Transformer (VT)**

**Symbol:**
```
  _____
 |     |
 |_____|  
    |
    |
```

**Function:**
A voltage transformer is used to measure the voltage in a circuit. It steps down the high voltage to a lower, manageable level, which can be safely used by protective relays and metering equipment.

---

**Note:** The symbols used above are simplified for clarity and might differ in different standards or diagrams. In practice, substation schematics and electrical diagrams will use more detailed and standardized symbols.

Answer 2

Certainly! Substations are critical components in electrical power systems, and various components within a substation each have specific functions. Here are six common components found in substations, along with their symbols and functions:

### 1. **Circuit Breaker (CB)**
- **Symbol**:
  
- **Function**: Circuit breakers are used to protect the electrical circuit from overloads and short circuits by automatically interrupting the flow of current when an abnormal condition is detected.

### 2. **Transformer (TR)**
- **Symbol**:
  
- **Function**: Transformers are used to step up or step down the voltage levels in the electrical system. They are essential for efficient transmission and distribution of electrical power.

### 3. **Disconnect Switch (DS)**
- **Symbol**:
  
- **Function**: Disconnect switches are used to isolate parts of the electrical system for maintenance or in case of faults. They ensure that the section of the system is completely de-energized before work is carried out.

### 4. **Current Transformer (CT)**
- **Symbol**:
  
- **Function**: Current transformers are used to measure the current flowing through a circuit. They provide a scaled-down current to meters and relays for monitoring and protection purposes.

### 5. **Voltage Transformer (VT)**
- **Symbol**:
  
- **Function**: Voltage transformers are used to measure the voltage in a circuit and provide a reduced voltage to instruments and relays for monitoring and protection.

### 6. **Earth Switch (ES)**
- **Symbol**:
  
- **Function**: Earth switches are used to safely ground electrical equipment for maintenance. They are crucial for ensuring that any residual or fault current is safely discharged to the ground.

These symbols and their functions are essential for understanding and operating substations efficiently and safely.