LVTS-5220-HVX high-voltage battery - BMS alarm page on the battery touchscreen (LVTOPSUN BMS protection alarms)
LVTopsun Dsg Ud_T error code
Battery temperature was below the BMS discharge window, so discharge was blocked.
Likely causes
- Cold installation or cold room
- Battery recently moved from a cold store
- Temperature sensor reading low
- Discharge attempted immediately after a cold start
Checks to run, in order
- 1Read the Temp Info page
- 2Measure ambient and cell temperature
- 3Check the installation against the datasheet temperature range
- 4Check whether the pack has heating and whether it is working
Fixes
- Warm the battery location before discharging
- Insulate the cabinet or move the battery indoors
- Wait for the pack to reach the operating window
When to escalate
If the display shows a low temperature while the pack is warm, ask the distributor to check the temperature 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 Dsg Ud_T mean?
Battery temperature was below the BMS discharge window, so discharge was blocked.
How do I fix LVTopsun Dsg Ud_T?
Warm the battery location before discharging Insulate the cabinet or move the battery indoors Wait for the pack to reach the operating window
When should I escalate LVTopsun Dsg Ud_T?
If the display shows a low temperature while the pack is warm, ask the distributor to check the temperature sensors.
Can I reset LVTopsun Dsg Ud_T myself?
Only after isolating the AC and DC sides and running the checks above. If LVTopsun Dsg Ud_T returns immediately, stop resetting it and escalate; a repeating fault usually points to a real circuit, battery or hardware problem.
Which models show LVTopsun Dsg Ud_T?
LVTopsun Dsg Ud_T 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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