LVTS-5220-HVX high-voltage battery - BMS alarm page on the battery touchscreen (LVTOPSUN BMS protection alarms)
LVTopsun Danger UV error code
Pack or cell voltage entered the BMS danger (second-level) under-voltage range.
Likely causes
- Deep discharge beyond the protection threshold
- Load left connected after the first under-voltage warning
- Weak cell collapsing under load
- Voltage sensing error
Checks to run, in order
- 1Stop discharge immediately and measure pack voltage at the terminals
- 2Read cell voltages and identify any cell far below the rest
- 3Check the inverter low-DC cut-off and whether the load was left on
- 4Compare the display with the meter
Fixes
- Isolate the load and recharge the pack as soon as possible
- Follow the manufacturer's over-discharge recharge procedure
- Do not return the pack to service until it holds voltage
When to escalate
A danger-level under-voltage can permanently damage cells: if the pack does not recover on recharge, have the distributor test it.
Fix it with the right tools
Check the system around the fault before replacing parts: load, battery bank, PV string and commissioning settings. If you need a second opinion, send the code and your inverter model to our team.
Before you open the inverter
- Isolate both the AC and DC sides, then confirm the display is dead before touching terminals.
- Use insulated tools and one hand where possible. DC arcs do not self-extinguish like AC.
- If you see burnt terminals, swollen cells, leaking electrolyte or a burning smell, stop and escalate instead of resetting the fault.
Questions installers ask
What does LVTopsun Danger UV mean?
Pack or cell voltage entered the BMS danger (second-level) under-voltage range.
How do I fix LVTopsun Danger UV?
Isolate the load and recharge the pack as soon as possible Follow the manufacturer's over-discharge recharge procedure Do not return the pack to service until it holds voltage
When should I escalate LVTopsun Danger UV?
A danger-level under-voltage can permanently damage cells: if the pack does not recover on recharge, have the distributor test it.
Can I reset LVTopsun Danger UV myself?
Only after isolating the AC and DC sides and running the checks above. If LVTopsun Danger UV returns immediately, stop resetting it and escalate; a repeating fault usually points to a real circuit, battery or hardware problem.
Which models show LVTopsun Danger UV?
LVTopsun Danger UV is documented for LVTS-5220-HVX high-voltage battery - BMS alarm page on the battery touchscreen (LVTOPSUN BMS protection alarms). Confirm the code on your own unit's display or manual before ordering parts.
More LVTopsun error codes
- LVTopsun Ahesion FltThe BMS detected a main contactor or relay that has stuck closed (contact adhesion).
- LVTopsun Chg Bat Ov_VThe pack voltage rose above the BMS charge over-voltage limit.
- LVTopsun Chg Bat Ud_VPack voltage stayed below the BMS charge under-voltage limit while the pack was supposed to be charging.
- LVTopsun Chg Cell Ov_VCharging was stopped because a cell reached the BMS charge over-voltage limit.
- LVTopsun Chg Cell Ud_VA cell fell below the BMS charge under-voltage limit while the pack was being charged.
- LVTopsun Chg Diff_TThe temperature difference between BMS sensors exceeded the limit during charge.
Guidance reviewed 17 October 2026 by the Mishka Energy installer team. Error codes vary by brand, model family and firmware; confirm against the manufacturer manual.
Back to troubleshooting