# FPV BATTERY → USB-A, Voltmeter + Cell Checker

“Checker USB” Converter Adapter is a compact device designed to convert FPV battery voltage into stable USB power.

Equipped with a built-in voltage tester featuring an LED display and an audible alarm, it allows you to monitor both the total battery voltage and the voltage of each individual cell.

Ideal for standalone operation in field conditions, including powering and charging electronic devices using FPV batteries.

## Technical Specifications

- Input: XT60-M and balance connector.

- Input Voltage: 8–30 V DC.

- Output: USB-A.

- Fast Charging: Supported.

- Power: Up to 65 W (short-term, depending on the installed module's capabilities).

- Display: Digital LED voltmeter.

- Battery Monitoring: Measures total battery voltage and individual cell voltages.

- Audible Alarm: Built-in buzzer with an adjustable voltage alarm threshold.

- Housing Material: PETG.

## Features

### Individual Cell Voltage Monitoring

The built-in checker allows you to monitor the voltage of individual FPV battery cells through the balance connector. This helps detect cell imbalance and monitor the battery's charge level.

### Low-Voltage Audible Warning

When the voltage reaches the preset threshold, the checker emits an audible alarm, warning you to stop using the battery.

### Universal USB-A Output

Allows you to charge smartphones, power banks, radios, tablets, and other compatible USB devices.

### Compact Housing

The lightweight 3D-printed housing makes the device easy to carry and convenient to use in field conditions.

## Instructions for Use

1. Connecting the Battery: Connect the XT60 connector to the FPV battery and the balance connector to the corresponding checker input, ensuring correct polarity.

2. Setting the Alarm: Use the button on the tester to set the low-voltage alarm threshold. For many LiPo batteries, a recommended reference range is 3.2–3.6 V per cell under load.

3. Voltage Monitoring: The LED display shows the battery voltage and individual cell voltages.

4. Charging Devices: Connect a compatible USB device to the USB-A port. Fast charging is activated when both devices support the corresponding charging protocol.

## Important Safety Information

WARNING!

- Do not exceed the maximum input voltage of 30 V.

- Do not allow the battery to become critically discharged.

- Always configure the audible alarm threshold before use.

- Do not use the device in wet conditions.

- Do not exceed the converter's maximum rated power.

- The audible alarm warns of low battery voltage but does not automatically disconnect the load.

- IT IS STRICTLY PROHIBITED TO USE THIS CONVERTER TO CHARGE FPV BATTERIES!