KONNWEI BK400 Wireless Battery Monitor 6V–48V

The KONNWEI BK400 is a wireless Bluetooth battery monitor and electrical-system tester designed to provide real-time visibility of battery voltage and vehicle electrical performance.

Supporting 6V, 12V, 24V and 48V systems, the BK400 is compatible with a wide range of battery types, including regular flooded, AGM flat plate, AGM spiral, EFB, GEL and lithium batteries.

The BK400 connects wirelessly to compatible Android and iOS devices through the dedicated BK400 app. Users can monitor real-time voltage, view waveform data, perform cranking and charging tests, monitor temperature and review battery information from their mobile device.

Up to six BK400 devices can be monitored simultaneously, making the system useful for monitoring multiple batteries or vehicles.

An integrated GPS location feature can also record the last location where the vehicle was parked or switched off.

Performance

• Voltage Range: 6V / 12V / 24V / 48V
• Input Range: 3–60V
• Input Current: Approximately 3mA
• Bluetooth: 5.2
• Wireless Range: Up to 32.8ft / 10m
• Real-Time Voltage Monitoring
• Voltage Waveform Display
• Cranking Test
• Charging Test
• Temperature Monitoring
• GPS Vehicle Location Feature
• Simultaneous Monitoring: Up to 6 devices
• Firmware Updates: Through the BK400 app
• Wireless Operation: Android and iOS devices

Battery Compatibility

The BK400 supports six battery types:

• Regular flooded lead-acid
• AGM flat plate
• AGM spiral
• EFB
• GEL
• Lithium

Its broad voltage range allows it to be used across different vehicle and battery applications, subject to the battery system's voltage and the manufacturer's recommended installation method.

Important: Compatibility with lithium batteries refers to monitoring and testing supported electrical parameters. The BK400 should not be treated as a comprehensive lithium battery pack diagnostic system.

Real-Time Monitoring

The BK400 provides continuous access to battery voltage information through the mobile application.

The app can display:

• Real-time voltage
• Voltage waveform
• Voltage collection data
• Temperature information
• Cranking test results
• Charging test results

Waveform data can help users observe changes in battery voltage during different operating conditions.

Cranking Test

The cranking test monitors battery voltage behaviour during vehicle starting.

This can help users assess the battery's electrical performance during engine cranking and identify unusual voltage drops that may warrant further investigation.

Cranking-test applicability depends on the vehicle and battery configuration.

Charging Test

The BK400 can monitor charging-system voltage to help assess the electrical system while the vehicle is operating.

This can provide useful information when investigating potential charging-system issues involving the battery, alternator or associated electrical components.

Temperature Monitoring

The BK400 can monitor battery temperature through the compatible monitoring system and display the available temperature data in the app.

Temperature information can provide additional context when assessing battery operating conditions.

GPS Location Feature

The integrated GPS location feature is designed to record the last location where the vehicle was parked or switched off.

This can be useful when monitoring multiple vehicles or locating where a monitored vehicle was last parked.

GPS functionality depends on the device, app and applicable permissions.

Multi-Device Monitoring

A single BK400 app can monitor up to six BK400 devices simultaneously.

This allows users to monitor multiple batteries or vehicles from a compatible Android or iOS device without needing to switch between separate monitoring sessions.

BK400 App

The dedicated BK400 application provides access to the monitor's functions.

• Real-time voltage display
• Waveform display
• Voltage collection
• Bluetooth name customisation
• Firmware updates
• Problem feedback
• Report sharing
• Language selection
• Multi-device monitoring

The app supports Android devices through Google Play and iOS devices through the App Store.

Specifications

Supported Languages

The BK400 app supports:

• Chinese

• Korean

• Portuguese

• English

• Italian

• Persian

• Japanese

• French

• Spanish

• Polish

• Russian

• German

• Dutch

Compatibility

The KONNWEI BK400 is designed for compatible 6V, 12V, 24V and 48V battery systems used across automotive and other electrical applications.

Supported battery types include:

• Flooded lead-acid
• AGM
• EFB
• GEL
• Lithium

Compatible mobile platforms:

• Android
• iOS
• iPad

Package Includes

• 1 × KONNWEI BK400 Wireless Battery Monitor

Important Notes

• A compatible Android or iOS device is required to use the BK400 application.
• Bluetooth range is approximately 32.8ft / 10m under suitable conditions.
• Battery monitoring and test functions depend on the battery type, voltage system and installation.
• The BK400 is primarily a monitoring and electrical-system testing device and should not be considered a replacement for professional battery-pack diagnostic equipment.
• Lithium battery support does not imply compatibility with every lithium battery chemistry or battery-management system.
• GPS functionality is intended to record the last vehicle location and may depend on device and application permissions.
• Do not exceed the specified input voltage range of 3–60V.