Whether the energy storage system needs to install combiner cabinets and the number of installations mainly depends on the scale, design requirements, and specific usage scenarios of the system. For large systems, especially those involving multiple battery modules or photovoltaic modules, it is usually necessary to set up a combiner cabinet. The core function of a combiner cabinet is to gather the currents from multiple power sources (such as battery modules and photovoltaic modules) to form one or more larger current outputs for subsequent inversion, grid connection, or direct power supply. In addition, it can effectively manage and protect the battery pack, thereby improving the efficiency and reliability of the system, while reducing the number of cables and simplifying the overall structure.
1、 Electrical component configuration of combiner cabinet
The electrical component configuration of the combiner cabinet usually includes:
1. Busbar/busbar: responsible for connecting multiple power sources and distributing current.
2. Circuit breakers, fuses, and fuses: used to control circuit switches, provide overcurrent protection, and prevent equipment damage caused by short circuits or overloads, with fuses being the last protective barrier.
3. Current monitor: Real time monitoring of the input and output currents of the system to ensure safety and stability.
4. Voltage converter: Adjust the voltage to an appropriate level as needed.
5. Connector: Used to securely connect input sources such as battery modules and photovoltaic modules to the combiner cabinet.
6. Wiring terminals: provide convenient interfaces for wiring, reducing wiring difficulty and error rates.
7. Protective devices, such as dust covers and insulation boards, protect internal electrical components from external environmental damage.
8. Contactor: Used to control the opening or closing of a circuit.
9. DC meter: monitors DC current and voltage.
10. Isolation knife switch: provides safe isolation for the maintenance of electrical equipment.
11. Surge Protective Devices (SPDs): Protect the system from sudden high voltages such as lightning strikes.
2、Steps for installing the combiner cabinet
1. Determine the optimal location for installing the combiner cabinet based on the specific requirements of the energy storage system, ensuring sufficient space for installation and subsequent maintenance.
2. Ensure that the installation environment meets relevant standards and prepare necessary tools (such as screwdrivers, wrenches, etc.) as well as materials such as cables and terminals.
3. Fix the bracket or foundation structure of the combiner cabinet in the predetermined position.
4. Install busbars, circuit breakers, current monitors, etc. one by one according to the design drawings and instructions.
5. Connect battery modules, photovoltaic modules, etc. to the input end of the combiner cabinet according to the circuit diagram to ensure correct connection.
6. After completing the wiring, conduct a comprehensive inspection to confirm that there are no omissions, and conduct preliminary electrical performance tests to ensure the safe and stable operation of the system.
7. After confirming that everything is normal, start the system and conduct a trial run, continuously monitor the operating status of the system, and keep records of relevant information.

3、The function of the combiner cabinet

1. Through centralized management of combiner cabinets, it is possible to effectively allocate and handle the current of multiple power sources, reduce losses during current transmission, and thereby improve the overall efficiency of the system.
2. The various protective devices built into the combiner cabinet, such as circuit breakers and fuses, can quickly cut off the power supply in case of system failure, effectively reducing the risks of overload and short circuit, thereby ensuring system safety and enhancing system reliability.
3. By centralized management, the number of cables and the complexity of the lines are reduced, making the system structure clearer. Meanwhile, when it is necessary to expand energy storage capacity, it can be easily achieved by adding new energy storage units and connecting them to existing combiner cabinets.
4. The modular design of the combiner cabinet makes system maintenance and upgrades easier. In addition, combiner cabinets are usually equipped with monitoring devices that can track changes in parameters such as current and voltage in real time, making it easy to identify and solve potential problems in a timely manner.
The combiner cabinet is one of the key components of the energy storage system, and its importance in the system is self-evident. Reasonable configuration and standardized installation of combiner cabinets can effectively ensure the stable operation of energy storage systems, improve their work efficiency, enhance reliability, and simplify the system structure. In the actual operation process, it is recommended to have professional technicians execute or guide to ensure compliance with relevant standards and safety regulations.