Low-Code ARM Control Unit in Smart City Street Lighting System

Introduction

With the rapid development of smart city initiatives, the intelligent management of urban infrastructure has become a critical means to enhance city operational efficiency and residents' quality of life. As a vital component of urban infrastructure, street lighting systems are increasingly in need of intelligent upgrades. The solution based on the BL340 ARM control unit combined with Node-Red low-code programming software offers an efficient, flexible, and easy-to-deploy control hub for smart street lighting. This article explores the application of this solution in smart city street lighting systems and its advantages.

System Overview

The BL340 series ARM embedded controller,  is an industrial-grade control unit powered by the Allwinner T507-H quad-core ARM Cortex-A53 processor, with a clock speed of up to 1.4 GHz. It supports 8/16 GB eMMC storage and 1/2 GB DDR4 memory. The controller features a rich set of interfaces, including three 10/100M Ethernet ports, two USB 2.0 ports, a Mini PCIe interface (supporting 4G/WiFi/Bluetooth modules), and flexible X/Y series IO board expansions for RS485, CAN, RS232, DI/DO, and more. Additionally, the BL340 supports multiple operating systems, including Linux, Ubuntu, and Android, and is compatible with the Node-Red low-code development platform, enabling rapid development of Internet of Things (IoT) applications.

Node-Red, an open-source low-code programming tool based on Node.js, simplifies IoT device data flow processing and protocol conversion through a visual drag-and-drop interface. Combined with the BL340’s hardware capabilities, Node-Red enables real-time monitoring, data acquisition, remote control, and seamless integration with cloud platforms for street lighting systems.

Requirements of Smart City Street Lighting Systems

Smart city street lighting systems need to meet the following core requirements:

1. Remote Monitoring and Control: Enable switching, brightness adjustment, and operational status monitoring of streetlights.
2. Energy Efficiency: Reduce energy consumption through ambient light sensing, timed control, or dynamic dimming.
3. Fault Detection and Maintenance: Detect streetlight faults in real time and send alerts for prompt maintenance.
4. Data Acquisition and Analysis: Collect data on light intensity, energy consumption, and environmental conditions to support urban management decisions.
5. Cloud Platform Integration: Seamlessly connect with mainstream IoT cloud platforms (e.g., AWS IoT, Alibaba Cloud IoT) for data storage and remote management.

System Architecture

The architecture of the smart street lighting system based on BL340 and Node-Red is as follows:

• Hardware Layer: The BL340 controller serves as the core control hub, connecting to streetlight sensors (e.g., light sensors, current/voltage sensors) and actuators (e.g., relays, dimming modules). A 4G module via Mini PCIe enables remote communication, while RS485 or CAN interfaces facilitate communication with streetlight devices.
• Software Layer: Node-Red runs on the BL340’s Linux or Ubuntu system, using a visual flow editor to handle data acquisition, processing, control logic, and cloud communication.
• Cloud Platform: The BL340, with BLIoTLink protocol conversion software, supports protocols like Modbus, MQTT, and OPC UA, integrating with cloud platforms such as AWS IoT and ThingsBoard for data storage, analysis, and remote management.
• User Interface: Users can monitor streetlight status, adjust control strategies, or receive fault alerts in real time via a web interface or mobile app.

Implementation

1. Hardware Configuration

Based on the ARMxy BL340 series datasheet, the following configuration meets the needs of the smart street lighting system:

• Model: BL340B-SOM341-X23-Y63
  • Host: BL340B (1×10/100M Ethernet port, 2×USB 2.0, 2×Y-series IO slots, dimensions 48×83×110 mm)
  • SOM Module: SOM341 (16 GB eMMC, 2 GB DDR4, -40~85°C industrial temperature range)
  • X-Series IO Board: X23 (4×RS485 ports, 4×DI, 4×DO, 20 PIN)
  • Y-Series IO Board: Y63 (4×RS485 or RS232 ports)
  • Expansion Module: Mini PCIe 4G module for remote communication.
• Sensors and Actuators:
  • Light Sensor: Connected via RS485 to collect ambient light intensity data.
  • Current/Voltage Sensor: Monitors streetlight energy consumption and operational status.
  • Relay Module: Controls streetlight on/off switching.
  • PWM Dimming Module: Adjusts brightness via PWM output from the Y-series IO board.

2. Node-Red Programming

Node-Red, running on the BL340, provides the following functionalities:

• Data Acquisition: Collects data from light and energy consumption sensors via RS485 nodes, storing it locally on eMMC or uploading it to the cloud.
• Control Logic:
  • Timed Control: Automatically turns streetlights on/off based on time schedules.
  • Ambient Sensing: Dynamically adjusts streetlight brightness based on light intensity.
  • Fault Detection: Monitors current/voltage anomalies and triggers alerts.
• Communication and Integration:
  • Uses MQTT nodes to push data to AWS IoT or Alibaba Cloud IoT.
  • Employs BLIoTLink for Modbus-to-MQTT protocol conversion.
  • Creates a web interface using Node-Red Dashboard nodes to display streetlight status and control options.
• Remote Maintenance: Uses BLRAT software for remote firmware upgrades and configuration management.

3. Deployment and Testing

• Installation: The BL340 supports DIN35 rail mounting, suitable for industrial environments in streetlight control cabinets. Its aluminum alloy casing and IP30 protection ensure reliability in outdoor settings.
• Testing:
  • Electromagnetic Compatibility: Per the datasheet, the BL340 passes GB/T 9254 Class A tests for radiated and conducted emissions, suitable for urban electromagnetic environments.
  • Environmental Suitability: Passes -40°C to 85°C high/low-temperature tests and IP30 protection tests, ensuring stable operation in extreme weather.
  • Functional Testing: Validates the correctness of Node-Red flows, ensuring proper data acquisition, control logic, and cloud communication.

Advantages

1. Low-Code Development, Rapid Deployment: Node-Red’s visual programming reduces the development barrier, allowing developers to implement complex control logic without deep coding expertise, shortening development cycles.
2. Flexible Expansion: The BL340’s X/Y-series IO boards and Mini PCIe interface support various sensors and communication modules, meeting diverse streetlight system customization needs.
3. Industrial-Grade Reliability: The BL340 passes high/low-temperature, vibration, and electromagnetic compatibility tests, making it suitable for urban outdoor environments.
4. Cloud Integration: Supports mainstream IoT protocols and cloud platforms, facilitating data analysis and remote management.
5. Cost Efficiency: The combination of a low-code platform and high-performance hardware reduces development and maintenance costs.

Conclusion

The BL340 ARM control unit, paired with Node-Red low-code programming software, provides an efficient and reliable solution for smart city street lighting systems. Its robust hardware performance, flexible expansion capabilities, and low-code development convenience meet the demands of intelligent, energy-efficient, and maintainable urban infrastructure. In the future, this solution can be extended to other smart city applications, such as intelligent transportation and environmental monitoring, offering greater possibilities for urban management.