The Fnirsi FNB58 is a professional digital USB voltmeter and cable tester designed to monitor voltage, amperage, and wattage in real-time. By connecting this device between a power source and your electronics, you can accurately measure electrical parameters including volts, amps, watts, ohms, and temperature, while also tracking total energy transfer. It features a 2-inch LCD display with multiple interface views and supports connectivity with Windows software and Android applications for advanced data analysis.
Advantages
This versatile tester provides comprehensive diagnostic capabilities for various USB standards, including USB-C, Micro USB, and USB-A. It excels at identifying fast-charging protocols such as QC2.0/3.0, FCP/SCP, AFC, USB PD2.0/3.0, and VOOC/WARP, while also reading E-marker chips in USB-C cables to verify cable quality and performance. Its ability to store data and interface with external software makes it an essential tool for troubleshooting complex charging issues and verifying power delivery efficiency.
Suitable for
- Monitoring real-time charging voltage and current
- Testing cable quality and data transfer capabilities
- Verifying fast-charging protocol compatibility
- Diagnosing power delivery issues in chargers and power banks
- Reading E-marker chip information in USB-C cables
When it may not be suitable
This device is intended for technical diagnostic purposes and may be overly complex for casual users who only require basic charging status. It is not designed for high-voltage industrial power systems outside of standard USB specifications.
Key specifications
- Display: 2-inch LCD
- Supported connections: USB Type-A, USB-C, Micro USB
- Measured parameters: Voltage, amperage, wattage, resistance, temperature, energy capacity
- Protocol support: QC2.0/3.0, FCP/SCP, AFC, USB PD2.0/3.0, VOOC/WARP, Super VOOC 1.0/2.0
- Connectivity: Windows software and Android app support
How to use
To use the Fnirsi FNB58, connect the tester directly into your power source or charger, then plug your USB cable and device into the tester. The device will automatically begin measuring the electrical flow. Use the interface buttons to toggle between the different display views on the LCD screen to view specific metrics. For advanced data logging and analysis, connect the tester to a Windows computer or a compatible Android device using the provided software or application.
What to consider before purchase
- Ensure your devices utilize the supported USB standards
- Check compatibility with your specific operating system for software features
- Verify if you require advanced protocol testing or simple voltage monitoring
Usage recommendations: Always ensure the tester is securely connected to both the power source and the device to prevent intermittent readings. When testing high-power devices, ensure the cable being tested is rated for the required amperage to avoid inaccurate results or potential overheating.
