Anti backflow electric meter

With the widespread application of distributed photovoltaic power generation systems, how to safely, compliantly, and efficiently manage photovoltaic grid connection has become a common concern for users and power grid companies. In this context, photovoltaic anti backflow meters (also known as "anti backflow metering meters" or "one-way metering meters") have emerged as key equipment to ensure the safety of distribution networks, meet policy and regulatory requirements, and optimize self use modes.

　　Introduction to Photovoltaic Anti Reverse Current Meter Products

With the widespread application of distributed photovoltaic power generation systems, how to safely, compliantly, and efficiently manage photovoltaic grid connection has become a common concern for users and power grid companies. In this context, photovoltaic anti backflow meters (also known as "anti backflow metering meters" or "one-way metering meters") have emerged as key equipment to ensure the safety of distribution networks, meet policy and regulatory requirements, and optimize self use modes.

　　1、 Working principle: Accurately identify and block "reverse current"

In traditional grid connected photovoltaic systems, if the user's electricity generation exceeds their electricity consumption, excess electricity will flow back into the public grid (i.e. "reverse flow"). However, in some areas (such as old residential areas and areas with limited transformer capacity), the power grid company explicitly prohibits or restricts backflow to prevent local overvoltage, equipment overload, or misoperation of protective devices.

The photovoltaic anti backflow meter uses high-precision bidirectional current sampling and real-time power direction judgment. Once it detects the transmission of electrical energy (i.e. reverse power) to the grid side, it immediately outputs control signals (such as dry contacts or communication commands), links with inverters or intelligent controllers, automatically reduces photovoltaic output or suspends power generation, thereby achieving "zero backflow" or "limited backflow" operation.

In short, only electricity is allowed to flow from the grid to users, and electricity is not allowed to flow from users to the grid.

　　2、 Core functional highlights

1. Bidirectional power monitoring and direction recognition

Real time measurement of active power direction, accurately distinguishing between "electricity consumption" and "power generation on grid" status.

2. The anti backflow threshold can be set

Support setting reverse flow thresholds to meet the policy differences of "prohibiting reverse flow" or "allowing trace reverse flow" in different regions.

3. Local control output interface

Provide control signal outputs such as relay dry contacts, RS485 Modbus, 4G/NB IoT, etc., which can be directly connected to inverters or energy management systems (EMS).

4. High precision measurement and data recording

Compliant with national standards for electric energy meters, with the ability to measure parameters such as forward active power, reverse active power, voltage, current, power factor, etc., and store event logs (such as the time and duration of reverse current occurrence).

5. Multiple security protections

Equipped with overvoltage, overcurrent, voltage loss, and phase interruption abnormal alarm functions, ensuring the safety of the interface between the photovoltaic system and the power grid.

　　3、 Technical advantages

Specially optimized for photovoltaic scenarios: Unlike ordinary bidirectional meters, anti backflow meters focus on the logic of "unidirectional electricity consumption+generation suppression", with simpler and more reliable control logic.

Plug and play, easy to deploy: The installation location is usually located at the user's main incoming line, without the need to modify the original distribution structure.

Strong compatibility: Supports communication protocols or hard wired control for branded inverters.

Remote operation and maintenance capability: supports remote parameter configuration, status monitoring, and fault diagnosis, reducing operation and maintenance costs.

　　4、 Typical application scenarios

1. Residential rooftop photovoltaics (without surplus electricity grid access permit)

In residential or rural areas where surplus electricity is not allowed to be connected to the grid, ensure that the photovoltaic power generation is "fully self used", and the excess is automatically reduced through anti backflow mechanisms.

2. Industrial and commercial distributed photovoltaic projects

For factories, shopping malls, schools and other places with insufficient transformer capacity or clear restrictions on reverse power transmission in the local power grid, ensure compliance with grid connection.

3. Energy storage+photovoltaic hybrid system

In the "integrated light storage" system, in conjunction with energy storage batteries, priority is given to consuming photovoltaic power, and anti backflow meters serve as the last line of defense to prevent the energy storage from being fully charged and still being sent back to the grid.

4. Power grid weak area renovation project

Used in areas with high load rates and aging lines in the substation, to avoid safety hazards caused by large-scale integration of distributed power sources.

　　5、 Compliance and Economic Value

Meet the requirements of grid connection policies: help users pass the acceptance of the power grid company smoothly, and avoid being forced to shut down or fined due to backflow problems.

Avoiding equipment risks: preventing voltage rise and harmonic pollution caused by backflow, and extending the lifespan of household appliances and distribution equipment.

Improve spontaneous self use rate: By implementing the operation strategy of "generating and using as much", increase photovoltaic revenue (especially in areas without grid subsidies).

Supporting green certification: providing reliable measurement basis for carbon footprint accounting and green electricity consumption certification.