PV String Monitoring (NSM8) provides high-precision current and voltage monitoring, wide compatibility, and intelligent data management. It can monitor 8-24 solar cell strings in real time, with a single string current accuracy of 20A and support for 1500VDC, meeting the needs of large power stations. It uses direct power supply from the solar array, without the need for an additional power supply, to improve energy efficiency. The RS485 interface and MODBUS protocol are seamlessly connected, supporting remote data acquisition and fault diagnosis, and reducing operation and maintenance costs. With 1500VDC high-voltage compatibility, multi-channel parallel monitoring, and MODBUS RTU protocol, it is suitable for distributed, industrial and commercial rooftops, and ground power stations. The modular design is flexibly adapted to projects of different sizes, facilitating refined power generation efficiency management, and is a core component for building smart photovoltaic pv sensor system.