Introduction
The KINGBOLEN BM520 is a professional automotive battery analyzer designed to test 6V, 12V, and 24V lead-acid batteries, including ordinary flooded, AGM flat plate, AGM wound, ACM spatial, EFB, and Gel batteries. It provides comprehensive analysis of battery health, cranking performance, and charging system efficiency. This manual will guide you through the features, setup, operation, and maintenance of your BM520 device.

Key Features
- Professional advanced testing and measuring algorithm applied.
- Enhanced hardware with improved insulation and high-quality current amplifier for stable and reliable results.
- Supports 6V, 12V, and 24V batteries, including cranking and charging system tests. Designed to withstand up to 50V.
- KINGBOLEN patented self-designed clamps for easy and accurate connection.
- Voltage waveform recording, playback, and deep analysis on a computer.
- Easy one-click lifetime free software updates via Mini USB interface.
- Multi-language interface support (English, Russian, German, French, Japanese, Dutch, Spanish, Italian, Portuguese, Polish, Simplified Chinese, Traditional Chinese).
- Large 2.8-inch HD TFT color screen display with backlight.
- Rugged keypad design with physical buttons for fast response and excellent tactile feedback.
- Non-slip design for comfortable one-handed operation.
- Integrated line machine design for stable connection and durable wire.
- High-quality pure copper wire with insulation, anti-interference layer, and outer silicone for durability.
- Reverse polarity protection: device operates normally even with incorrect polarity, preventing damage to the device and battery.
- Screenshot function to capture and save important data (up to 10 pictures).

Package Contents
Verify that all items are present in your package:
- 1x KINGBOLEN BM520 Battery Tester with Alligator Clips
- 1x User Manual
- 1x Leather Box (carrying case)
- 1x Product Packaging Box

Specifications
| Parameter | Value |
|---|---|
| Product Name | Battery Tester |
| Product Color | Black |
| Model Number | BM520 |
| Product Size | 7.50 x 3.55 x 1.02 inches |
| Connection Method | Big bite force alligator clip |
| Screen Size | 2.8 Inch TFT color screen |
| Test Range | 6V/12V/24V Battery (100-2000 CCA) |
| Operating Voltage | 5~32V |
| Operating Temperature | -20°C~65°C |
| Product Material | PVC Industrial Material |
| Supported Battery Types | EPS lead-acid, Car start, AGM/EFB start-stop, Electric vehicle, UPS lead-acid, Gel battery |
| Supported Test Standards | CCA, BCI, CA, MCA, JIS, DIN, IEC, EN, SAE, GB |
| Language Support | English, Russian, German, French, Japanese, Dutch, Spanish, Italian, Portuguese, Polish, Simplified Chinese, Traditional Chinese |
Note: All data are measured in the laboratory with reasonable errors. Please refer to the actual product.


Setup and Connection
- Prepare the Battery: Ensure the battery terminals are clean and free of corrosion for accurate readings.
- Connect the Clips:
- Connect the red alligator clip to the positive (+) terminal of the battery.
- Connect the black alligator clip to the negative (-) terminal of the battery.
The BM520 features reverse polarity protection, meaning the device will still function and will not be damaged even if the clips are connected incorrectly. However, always strive for correct connection for best practice.
- Power On: The device will automatically power on once connected to the battery.
- Language Selection: If needed, navigate to the 'Setup' menu to select your preferred language. The device supports multiple languages including English, Russian, German, French, Japanese, Dutch, Spanish, Italian, Portuguese, Polish, Simplified Chinese, and Traditional Chinese.


Operating Instructions
The BM520 offers several testing functions accessible via the main menu. Use the navigation buttons (Up, Down, Left, Right) and the 'OK' button to select options.
Main Test Functions:
- Battery Test: Measures battery life, voltage, Cold Cranking Amps (CCA), and internal resistance.
- Cranking Test (Start The Test): Evaluates the battery's discharge performance during engine startup.
- Charging Test (Load Test): Assesses the engine's charging system performance.
- Ripple Test: Checks the stability of the charging system by measuring waveform fluctuations. A smaller fluctuation indicates a healthier charging system.

Detailed Test Procedures:
Battery Test
- From the main menu, select "Check" or "Battery Test".
- Follow the on-screen prompts to input battery type (e.g., Flooded, AGM, Gel) and CCA rating if required.
- The tester will display results for Voltage, CCA, Internal Resistance, and Battery Life/Health.
Cranking Test
- From the main menu, select "Cranking Test" or "Start The Test".
- Ensure the engine is off.
- Follow the on-screen instructions to start the engine. The tester will monitor the battery voltage during cranking.
- Results will indicate the cranking voltage and overall cranking performance.
Charging Test
- From the main menu, select "Charging Test" or "Load Test".
- Ensure the engine is running.
- The tester will measure the alternator's output voltage and ripple.
- Results will indicate if the charging system is functioning correctly.
Ripple Test
This test is typically part of the Charging Test. The device analyzes the AC ripple voltage generated by the alternator. High ripple voltage can indicate issues with the alternator's rectifier diodes.

Note on Ripple Test Results: If the test result is normal, the battery is charged normally. If the voltage reading is greater than 15.0V (for a 24V system, greater than 30.00V), please check the voltage regulator. If the voltage reading is less than 13.3V (for a 24V system, less than 26.60V), please check the connection points, wires, and engine.
Advanced Functions:
Voltage Waveform Monitoring
The BM520 can monitor battery voltage in real-time, displaying the current floating size of the battery voltage. It automatically stores and allows playback of up to 10 waveform data sets for deep analysis.

Screenshot Function
To capture and save important data displayed on the screen, long-press the "Up Arrow" and "Down Arrow" buttons simultaneously. The device can store up to 10 screenshots.

Maintenance
- Cleaning: Wipe the device with a soft, dry cloth. Do not use abrasive cleaners or solvents.
- Storage: Store the BM520 in its protective leather box in a cool, dry place when not in use.
- Cable Care: Avoid sharp bends or excessive pulling on the integrated cable to prevent damage. The high-quality wire is designed for durability but proper handling extends its lifespan.
- Software Updates: The BM520 supports lifetime free software updates. Connect the device to a computer via the Mini USB interface for updates. No driver installation is needed; the process is simple and easy to operate.


Troubleshooting
| Problem | Possible Cause | Solution |
|---|---|---|
| Device does not power on. | Poor connection to battery terminals; battery voltage too low. | Ensure alligator clips are securely connected to clean battery terminals. Check if the battery has sufficient voltage (min 5V operating voltage). |
| Inaccurate readings. | Corroded battery terminals; incorrect battery type/CCA input; extreme temperatures. | Clean battery terminals. Verify correct battery type and CCA values are entered. Operate within specified temperature range (-20°C to 65°C). |
| Ripple Test shows abnormal results (voltage too high/low). | Faulty voltage regulator; loose connections; engine issues. | Check the voltage regulator. Inspect all connection points and wires. Consult a professional for engine diagnostics if necessary. |
| Software update fails. | Loose USB connection; corrupted update file. | Ensure a stable USB connection. Re-download the update file from the official KINGBOLEN website if available. |
| Screen is blurry or unreadable. | Screen protector still on; display settings. | Remove any protective film from the screen. Check display settings in the 'Setup' menu if applicable. |
User Tips
- For consistent results, always test the battery when it is fully charged and at a stable temperature.
- When performing the Cranking Test, ensure all non-essential electrical loads are turned off in the vehicle.
- Utilize the screenshot function to save important test results for future reference or sharing with a mechanic.
- Regularly check for software updates to ensure your device has the latest features and improved algorithms.
- The device's ability to test 6V, 12V, and 24V batteries makes it versatile for various vehicles, from motorcycles to heavy-duty trucks.
Warranty and Support
The KINGBOLEN BM520 comes with a manufacturer's warranty. Please refer to the warranty card included in your package or contact KINGBOLEN customer support for details regarding warranty coverage and service.
For technical support, software updates, or any inquiries, please visit the official KINGBOLEN website or contact their customer service department.





