Reverse Power Protection Device

When a photovoltaic (PV) power station is designed for irreversible grid connection, a reverse power protection device (also known as an anti-reverse current protection device) should be configured at the grid connection point. Our company's SMR-4910BG reverse power protection device is a microprocessor-based device specifically designed for this purpose. It monitors the low-voltage side of the distribution transformer in real time, enabling necessary control of the clean power supply.

Three-stage current protection: includes instantaneous overcurrent, delayed instantaneous overcurrent, and overcurrent protection; all three stages have undervoltage and directional blocking functions, and can be individually enabled or disabled;

Six-time-limit reverse power protection tripping output;

Six-time-limit reverse power recovery function;

Undervoltage protection: alarm;

Overvoltage protection: alarm;

PT disconnection detection.

**High Integration and Modular Design:** Core functional modules (such as power supply and CPU modules) are clearly defined, facilitating production, debugging, and subsequent maintenance. If a component fails, the corresponding module can be quickly located and replaced.

**Compact Housing and Standardized Installation:** The robust housing effectively shields against electromagnetic interference, ensuring stable operation in complex industrial electromagnetic environments.

**User-Friendly Human-Machine Interface:** Real-time display of all key electrical parameters, including three-phase current, voltage, active power, reactive power, and frequency, as well as device status, setting information, and event logs. All protection settings can be set and queried via panel buttons, eliminating the need for external computers or specialized debugging tools, making on-site debugging extremely convenient.

**Powerful Terminal Blocks and Isolation Design:** Opto-isolation or transformer isolation is used between analog inputs (PT/CT secondary side) and internal low-voltage circuits, as well as between digital input/output circuits, effectively preventing field interference from entering the core of the device and ensuring its safety.

Primarily used in thermal power plant steam turbines, hydroelectric power station turbines, industrial self-owned power plants, ship power stations, and all other applications requiring protection against "generator-to-motor" operation. Features include precise reverse power protection, comprehensive auxiliary protection functions, a standard communication interface, complete fault logging, and high environmental adaptability.

Baoding Simaier Electric Co., Ltd. was established on July 1, 2009 and is located in the National High-tech Industrial Development Zone of Baoding City, Hebei Province. It is a high-tech enterprise focusing on the research and development of power system automation, relay protection and instrumentation.