What communication methods are supported by prepaid smart meters in supermarkets?

Analysis of mainstream communication methods for prepaid smart meters in supermarkets

In the scenario of electricity management in supermarkets, the communication stability, data transmission efficiency, and cost control of prepaid smart meters directly affect the efficiency of electricity management. At present, mainstream communication methods can be divided into two categories: wired communication and wireless communication. Different methods have significant differences in technical characteristics and applicable scenarios. The following is a detailed breakdown:

1、 Wired communication method: stable priority, suitable for fixed scenarios

Wired communication relies on physical lines to transmit data and has the core advantages of strong anti-interference ability and stable data transmission. It is suitable for scenarios where the location of electricity meters in supermarkets is fixed and wiring conditions permit. Common types include:

RS485 bus communication

Technical features: Adopting differential signal transmission, communication distance can reach 1200 meters, supporting parallel networking of multiple meters (up to 32), transmission rate between 9600-115200bps, and low data error rate.

Supermarket adaptability: Suitable for small and medium-sized supermarkets or single story stores. When the electricity meters are installed in fixed areas such as distribution rooms and vertical shafts, they can be directly connected to the management host through a bus to achieve real-time uploading of electricity bill data and issuance of power outage instructions for overdue payments. But it is necessary to plan the wiring in advance, as the cost of later renovation is high, and line failures may cause local electricity meters to go offline.

Typical application: Electricity meters in key power consumption areas such as supermarket refrigeration areas and cash registers, which need to ensure real-time and stable data to avoid deviation in electricity bill statistics due to communication interruptions.

Power Line Carrier Communication (PLC)

Technical features: Utilizing existing power lines to transmit data without the need for additional wiring, the communication distance extends with the power lines (theoretically up to several kilometers), and supports cross station networking (requiring the use of concentrators).

Supermarket adaptability: Suitable for large chain supermarkets or multi-level complexes, it can directly use the existing power supply lines to achieve meter networking, reducing the impact of construction on business. However, due to the significant impact of power grid harmonics and load changes, communication delays may occur during peak electricity consumption periods (such as holiday promotions), and signal amplifiers need to be used to enhance stability.

Advantage scenario: Supermarket zoning electricity metering (such as food and clothing areas) can achieve zoning electricity fee statistics and prepaid management without the need for rewiring.

2、 Wireless communication method: flexible deployment, adaptable to complex scenarios

Wireless communication does not require physical lines and has high deployment flexibility, making it suitable for scenarios where electricity meters are scattered and wiring is difficult within supermarkets. The mainstream types include:

LoRa wireless communication

Technical features: Adopting spread spectrum technology, communication distance can reach 3-5 kilometers (in open environments), strong penetration ability (can penetrate 2-3 layers of walls), low power consumption (a single battery can provide power for 3-5 years), supporting star and mesh networking.

Supermarket adaptability: Perfectly adapted to multi-level scenarios such as large supermarkets and shopping centers, electricity meters can be installed in different floors and areas, and data can be aggregated through LoRa gateway without wiring. Even in environments with dense shelves and many walls, stable communication can still be maintained, and new electricity meters can be quickly connected in the future without the need to modify existing lines.

Core advantages: support remote recharging (users recharge through APP and official account, and data is synchronized to the electricity meter in real time), remote switch on/off, reduce the cost of manual inspection of supermarket operators, especially for convenience stores and supermarkets operating 24 hours a day.

NB IoT (Narrowband Internet of Things) communication

Technical features: Based on operator networks (China Mobile, China Unicom, China Telecom), wide coverage (relying on base station signals, cross regional management can be achieved), low speed (transmission rate 160-250kbps), low power consumption (battery life 3-10 years), supporting massive connections (a single base station can connect 100000 devices).

Supermarket adaptability: Suitable for cross store management of chain supermarkets, the headquarters can monitor the electricity meter data (electricity consumption, remaining electricity fees, equipment status) of various stores across the country in real time through a cloud platform, without the need to build a dedicated gateway. However, SIM card data fees need to be paid, and communication interruptions may occur in areas with weak signals (such as underground supermarkets and remote stores), requiring the use of a signal booster.

Typical application: The headquarters of a chain supermarket can remotely monitor the electricity usage of stores in remote areas to detect any incidents of electricity theft or leakage, and issue timely warnings of overdue payments.

WiFi communication

Technical features: Based on local area network or public WiFi, with high transmission speed (150-600Mbps), strong real-time data, and support for bidirectional communication (electricity meter data upload, remote command issuance).

Supermarket adaptability: Suitable for small and medium-sized supermarkets with stable WiFi networks, the electricity meter can be directly connected to existing WiFi without additional hardware costs. But the communication distance is short (about 100 meters in open environments, greatly affected by wall and shelf obstruction), and data loss may occur when the WiFi network load is too high, which is not suitable for scenarios where electricity meters are scattered and have a wide coverage area.

Applicable scenario: The electricity meter near the supermarket checkout counter needs to synchronize real-time electricity data to the checkout system, making it convenient for users to recharge on site and immediately power on.

3、 Suggestions for selecting communication methods: Match core requirements with supermarket scenarios

Small and medium-sized single store supermarkets: prioritize RS485 bus (low wiring cost, high stability) or WiFi communication (relying on existing networks for quick deployment). If there is a need for expansion in the future, LoRa gateway interface can be reserved.

Large supermarkets/shopping centers: LoRa wireless communication is recommended, which balances coverage, penetration capability, and deployment flexibility. It can achieve centralized management of multi-layer and multi area electricity meters and support remote operation and maintenance.

Chain type cross regional supermarkets: NB IoT communication is preferred, relying on the operator's network to achieve unified control of each store by the headquarters, without the need to build a dedicated network, reducing cross regional management costs.

Upgraded supermarkets (with existing power supply lines): Priority should be given to power line carrier communication (PLC), using the existing lines to reduce the impact of construction on business. If there is power grid interference, LoRa gateway can be used to achieve hybrid networking.

4、 Future Trends: Hybrid Networking and Intelligent Upgrades

With the increasing demand for refined electricity management in supermarkets, a single communication method is gradually developing towards a hybrid network of "wired+wireless" (such as RS485+LoRa, PLC+NB IoT), which not only ensures communication stability in core areas, but also considers flexible deployment in dispersed areas. At the same time, communication technology will be combined with AI algorithms to achieve real-time electricity load prediction and abnormal electricity warning (such as equipment leakage and overload) through electricity meter data, further improving the safety and energy-saving efficiency of supermarket electricity use.