BYD Premium HVS SOC Dropping Suddenly from 20 to 0 –... | solarfaults.org

Technical Background:

The sudden drop in SOC may trigger an inverter fault due to the battery's inability to maintain voltage levels under load. The Battery Management System (BMS) continuously monitors the SOC and voltage of the battery cells. If it detects conditions that could lead to cell damage or unsafe operation, it may trigger a protective response, cutting off power to prevent further degradation. Factors such as insulation resistance measurement (RISO) failures or ground fault detection can also lead to an inverter shutdown, as these conditions indicate potential hazards in the electrical system.

Symptoms:

Homeowners may observe that the State of Charge (SOC) on their BYD Premium HVS battery suddenly drops from 20% to 0%. This can be accompanied by LED indicators on the battery unit flashing red or yellow, and monitoring apps may show alerts for low battery status or system faults. Additionally, there may be a noticeable drop in power supply to connected loads.

Possible Causes:

Sudden load demand exceeding battery capacity.
Faulty Battery Management System (BMS) reporting incorrect SOC.
Poor connections or corrosion at terminals leading to voltage drops.
Internal battery cell failure or imbalance.
Temperature extremes affecting battery performance.
Inadequate charging due to inverter or grid issues.

Solution:

1

Verify the load connected to the battery; ensure it does not exceed rated capacity.
2

Check the BMS settings and firmware; update if necessary.
3

Inspect all terminal connections for corrosion or looseness, and clean or tighten as needed.
4

Measure the voltage of individual battery cells using a multimeter to identify any discrepancies.
5

Assess ambient temperature conditions and ensure the battery is within operational limits.
6

Confirm the inverter settings and grid connection are functioning properly, including checking for any fault codes.
7

If issues persist, consult the manufacturer for advanced diagnostics or consider replacing the battery.

Safety Warning:

Always consult a licensed electrician or certified solar installer for troubleshooting and repairs to ensure safety and compliance with local codes.

Prevention:

To avoid future occurrences of SOC drops, regularly maintain the battery system by cleaning terminals, updating BMS firmware, and monitoring load demands. Ensure that the system is installed in a climate-controlled environment and check for any signs of wear or damage to the battery and connections.

Frequently Asked Questions

•What causes SOC to drop suddenly in batteries?

A sudden drop in State of Charge (SOC) can be caused by a malfunctioning battery management system, internal short circuits, or excessive load. It's essential to check the battery's health and connections.

•How can I troubleshoot this SOC issue?

Start by inspecting the battery connections and ensuring they are secure. Next, check for any error codes on the battery management system and consult the user manual for further diagnostics.

BYD Premium HVS SOC Dropping Suddenly from 20 to 0 – Troubleshooting & Technical Fix Guide

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention:

Frequently Asked Questions

•What causes SOC to drop suddenly in batteries?

•How can I troubleshoot this SOC issue?

Related questions

Technical Background:

Symptoms:

Possible Causes:

Solution:

Safety Warning:

Prevention: