JK Inverter BMS 100% Reset and Charging Algorithm explained!
TL;DR
This video explains how to correctly set up the JK Inverter BMS for reliable 100% state of charge resets by detailing the critical RCV, SOC 100% voltage, and RCV timer parameters, and explores various charging algorithms including float mode and the newer rebulk SOC feature.
Key insights
Correctly resetting the JK Inverter BMS to 100% requires understanding three key parameters.
- Requested Charge Voltage (RCV) sets the maximum charging voltage.
- State of Charge 100% Voltage is set slightly lower than RCV to trigger the reset.
- RCV Timer dictates how long the BMS holds the RCV voltage, allowing for absorption and cell balancing before resetting.
The JK Inverter BMS offers different charging algorithms based on firmware versions and user preferences.
- Disabling float mode allows for extended absorption and top balancing.
- Float mode maintains a lower, battery-friendly voltage after full charge.
- Newer firmware (v19.10+) replaces the RFV timer with 'rebulk SOC' to prevent daily full recharges in UPS or standby scenarios.
The JK Inverter BMS app's status screen is crucial for monitoring and troubleshooting the charging process.
- Users can observe the current charge status (Bulk, Absorption, Float).
- The RCV timer's countdown is visible, aiding in understanding the absorption phase.
- These status indicators help diagnose why the BMS might not be resetting correctly.
Key moments
- 01:17Introduction to the JK Inverter BMS and the importance of three key settings for a reliable 100% reset: RCV, SOC 100% voltage, and RCV timer.
- 03:52Explanation of the charging algorithm using a diagram, illustrating how the RCV voltage, RCV timer, and SOC 100% voltage interact to achieve a full charge and BMS reset.
- 07:04Troubleshooting common issues where the BMS may not reset to 100%, often due to the battery voltage being below the SOC 100% voltage at the end of the RCV timer.
- 08:52Demonstration of the JK Inverter BMS app's status screen, showing charge status and the RCV timer, and emphasizing the importance of these three parameters for correct setup.
- 11:00Overview of the charging algorithm without float mode, highlighting its use for full top balancing, and the algorithm with float mode enabled, which lowers voltage for battery longevity.
- 14:56Explanation of the newer charging algorithm in firmware versions 19.10 and above, featuring 'rebulk SOC' instead of the RFV timer, allowing users to set a discharge threshold before the battery recharges to full.