LVTS-5220-HVX high-voltage battery - BMS alarm page on the battery touchscreen (LVTOPSUN BMS protection alarms)
LVTopsun Danger UT error code
Temperature entered the BMS danger under-temperature range.
Likely causes
- Very cold installation or cold store
- Battery moved into a cold environment and energised immediately
- Temperature sensor fault
- Heating system failure (where fitted)
Checks to run, in order
- 1Stop charge and discharge
- 2Measure the actual pack and ambient temperature
- 3Check the sensor readings against a thermometer
- 4Check any fitted heating circuit
Fixes
- Move the battery to a location inside the operating range
- Wait for the pack to warm before restarting
- Do not charge below the datasheet temperature limit
When to escalate
If the reading shows a danger low temperature while the pack is warm, ask the distributor to check the sensors.
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 UT mean?
Temperature entered the BMS danger under-temperature range.
How do I fix LVTopsun Danger UT?
Move the battery to a location inside the operating range Wait for the pack to warm before restarting Do not charge below the datasheet temperature limit
When should I escalate LVTopsun Danger UT?
If the reading shows a danger low temperature while the pack is warm, ask the distributor to check the sensors.
Can I reset LVTopsun Danger UT myself?
Only after isolating the AC and DC sides and running the checks above. If LVTopsun Danger UT 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 UT?
LVTopsun Danger UT 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.
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