What are the components of a box - type substation?

The packaged substation (prefabricated substation) is an integrated power distribution device, mainly composed

 of the following modules. Each part works in coordination to achieve the functions of high-voltage power distribution, 

voltage transformation, and low-voltage distribution:

### I. High-voltage Power Distribution Unit

1. **High-voltage Switchgear**

   - Ring main unit or circuit breaker cabinet: Used to control the high-voltage incoming line, including vacuum circuit 

breakers, load switches, and disconnectors.

   - Lightning arrester: Protects the equipment from damage caused by lightning overvoltage.

   - Voltage/current transformer: Monitors the electrical parameters on the high-voltage side.

2. **Protection Devices**

   - Relay protection module: Achieves protection against short circuits, overloads, and grounding faults.

### II. Transformer Unit

1. **Transformer Body**

   - Oil-immersed transformer (commonly used outdoors) or dry-type transformer (for indoor/environmentally 

friendly scenarios).

   - The capacity is usually between 315kVA and 2500kVA, and the common voltage levels are 10kV/0.4kV.

2. **Temperature Control and Cooling System**

   - Oil-immersed type: Radiators, oil temperature gauges, and fans (optional).

   - Dry type: Natural air cooling or forced air cooling devices.

### III. Low-voltage Power Distribution Unit

1. **Low-voltage Power Distribution Cabinet**

   - Main circuit breaker: Controls the total output and has overload and short-circuit protection.

   - Branch circuit breakers/fuses: Distributes power to different electrical circuits (such as lighting and power).

   - Reactive power compensation device: Capacitor banks to improve the power factor.

2. **Monitoring and Metering**

   - Electric energy meters, ammeters, voltmeters, and multi-functional power meters.

### IV. Shell and Structure

1. **Enclosure**

   - Materials: Cold-rolled steel plates (with anti-corrosion spraying), stainless steel, or composite materials.

   - Protection level: IP54~IP65, meeting the outdoor requirements for water and dust prevention.

2. **Internal Layout**

   - Modular design: The high-voltage room, transformer room, and low-voltage room are independently separated.

   - Maintenance passage: Equipped with openable doors, lighting, and safety locks.

### V. Auxiliary Equipment

1. **Intelligent Components**

   - Remote monitoring system (RTU): Supports functions such as remote measurement, remote signaling,

 and remote control.

   - Temperature and humidity sensors: Automatically starts and stops the fans or heaters.

2. **Accessories**

   - Cable terminals: High-voltage cable joints, low-voltage busbars.

   - Grounding system: Main grounding terminals and lightning protection grounding devices.

### Application Scenarios

- **Power Distribution Field**: Residential communities, commercial complexes, industrial parks.

- **Temporary Power Supply**: Construction sites, large-scale event venues.

- **Special Environments**: Remote areas such as islands and mountainous areas (optional solar complementary

 systems).

### Summary of Features

- **Integration**: Integration of high-voltage power distribution, voltage transformation, and low-voltage power

 distribution, reducing civil engineering costs.

- **Flexibility**: Capacity, number of outgoing circuits, and intelligent functions can be customized according to

 requirements.

- **Reliability**: Fully sealed design, adaptable to harsh climates, and long maintenance cycle.

Through modular design and intelligent upgrades, the packaged substation has become an efficient and flexible 

key node in the modern power distribution network.