Link Repack - Protek B801 Manual
The manual shows a specific wiring order: Reversing this can confuse the cell voltage detection.
A: On DC power, your source battery or power supply has dropped below 11V. Increase your power supply or use AC input. protek b801 manual link
While there is no single "essay" available as a standalone manual for the Protek B801, you can find official documentation and technical support through the following resources: : The manual shows a specific wiring order: Reversing