Project
This project involved designing a compact, single-channel battery data logger to monitor and log the performance of lead-acid batteries powering surveillance systems in large warehouse environments.
Product Overview
The Single Channel Voltage and Current Data Logger is a battery-powered logging device designed to continuously monitor the voltage, charging/discharging current, and temperature of a single lead-acid battery.
A standout feature of this device is that it runs directly on the monitored battery itself, consuming extremely low current so that it does not drain the battery significantly. In addition, an optional 9 V external input is provided, allowing flexible power options depending on the installation scenario.
Key highlights:
- Hall-effect current sensing to measure DC current and detect charging/discharging cycles.
- Local SD card storage (FAT32, Windows-compatible) for secure data logging.
- LCD alphanumeric display showing live voltage, current, and temperature readings.
- USB interface for PC connectivity and configuration.
- Ultra-low power design for efficient standalone battery monitoring.
Working Principle
-
Battery Connection: The positive and negative terminals of the battery connect to the BAT port on the logger.
-
Current Measurement:
- A Hall-effect current transformer (CT) is installed on the negative cable.
- The CT senses magnetic flux when current flows, converts it into a proportional voltage, and the onboard ADC digitizes it into real current readings.
- Current direction is also detected to differentiate between charging and discharging cycles.
-
Voltage & Temperature Measurement:
- Voltage readings are digitized via the ADC.
- Temperature is captured by integrated sensor channels.
-
Data Logging:
- Logged values (voltage, current, temperature, timestamp) are saved in CSV format on the SD card.
- Logs can be read directly in Windows or via USB using the utility software.
-
Power Flexibility:
- Primary Mode: Operates directly on the monitored battery.
- Optional Mode: Can be powered externally using a 9 V input.
- A wakeup button turns the LCD display ON temporarily, which automatically shuts off to conserve energy.
Software Utility
A custom Windows-based software utility was developed to make the device easy to configure and operate:
- Log Retrieval: Access and download recorded log files directly via USB.
- Log Export: Export logged data in csv formats for further analysis and reporting.
- Live Monitoring: View real-time voltage, current, and temperature values.
- Parameter Settings: Configure scanning/logging interval, synchronize RTC (date and time), and adjust system parameters.
- User-Friendly Interface: Intuitive design for easy operation, making it suitable for both technical and non-technical users.
This software ensures that data retrieval and device configuration are seamless, providing a complete monitoring solution when paired with the logger.
Product Specifications
| Feature | Specification |
|---|---|
| Voltage Channels | 1 (0–20 V DC) |
| Current Channels | 1 (Hall-effect CT, ±30 A DC) |
| Voltage Accuracy | ±50 mV |
| Temperature Measurement | Supported |
| Local Storage | micro-SD (up to 16 GB, FAT32) |
| Display | LCD Alphanumeric display |
| Power Supply | Runs directly on monitored battery, optional 9 V input |
| Indicators | LED for power and logging |
| Connectivity | USB port for PC access and configuration |
| Timekeeping | Onboard RTC (Real-Time Clock) |
| Software | Windows utility for log retrieval, live display & configuration |
Benefits & Applications
- Warehouse surveillance battery monitoring – Ensures reliable backup power for critical systems.
- Smart battery management – Detects charge/discharge cycles and provides alerts for failures.
- Standalone operation – Works directly on the battery, with optional external power if needed.
- User-friendly – Local LCD display + PC utility for easy setup and monitoring.
- Reliable logging – SD card storage ensures data integrity even without external connectivity.
Product Photos/Videos
