There are many reasons for the fire of PV power station. The equipment with high fire risk include inverter, combiner box, cable and components. As long as it is an electrical system, there is a risk of fire due to current. In addition, with the progress of PV technology, the power level and current voltage of PV products continue to improve. The PV system has been improved from the initial 600V design to 1000V, and recently gradually upgraded to 1500V. Higher voltage is more likely to cause fire. The fire of PV power station poses a great challenge to the fire brigade. After a fire occurs in the system, high voltage of hundreds or even thousands of volts will still be generated. If firefighters rush to rescue, it will threaten the lives of firefighters. With thePV Panel Level Rapid Shutdown Switch function, firefighters can quickly cut off the connection between components and rescue the power station.
Inverters are mainly divided into centralized inverter, series inverter and micro inverter. Among the three types of inverters, only the micro inverter has this function, and the other two types of inverters do not have the component level fast shutdown function. The micro inverter system adopts full parallel circuit design, which can invert the DC current of each module into AC and then connect it to the power grid. There is only about 60V DC voltage, which has the advantage of natural no DC high voltage. It completely solves the risk of fire caused by high-voltage DC arcing, and also solves the problem that the rescue is hindered by PV power station when the house is on fire. However, micro inverters only occupy a small part in the PV inverter market. Most systems still use conventional centralized or series inverters, so such inverters need to be equipped with specific devices to realize the component level fast shutdown function. The use ofPV Panel Level Rapid Shutdown Switch equipment is the simplest, mature and can meet this requirement.
What is PV Panel Level Rapid Shutdown Switch?
The PV Panel Level Rapid Shutdown Switch of safety guard is a device that can realize PV Panel Level Rapid Shutdown Switch. In case of emergency, the device can quickly shut down the connection between each PV module remotely or manually, so as to eliminate the DC high voltage in the PV system array, reduce the risk of electric shock and solve the rescue risk. The safety guard component level shut-off has many advantages, such as safety and reliability, flexible installation, high efficiency, low noise and so on. Dual channel DC input, greatly reducing the installation cost; Comply with the requirements of NEC 2017 & 2020 (690.12) and sunspec certification; Small size and light weight, which can be directly stuck on the component frame or pasted on the component back plate; Imported chips are adopted, with more powerful functions, higher integration and fewer components; Lower power loss, lower minimum operating voltage (8V) and longer component operating time; The noise of ERP products is much lower than the arc noise, and the arc detection (AFCI) will not be triggered by mistake.
The PV Rapid Shutdown system (ERP) of the safety guard is one of the important safety components of the distributed PV system. Its function is to reduce the voltage beyond 30cm from the PV module to less than 30V within 30s after starting the shutdown equipment. When the building where the PV module is located needs maintenance or fire rescue, it can effectively prevent potential safety hazards such as electric shock and ensure the life safety of maintenance personnel and firefighters. In addition to meeting the requirements of NEC 2017 and 2020 (690.12) fast shutdown regulations, its unique component monitoring function can monitor the component status in real time, find component problems and faults in time, and further improve the intelligence and reliability of components.