LVTS-5220-HVX high-voltage battery - BMS alarm page on the battery touchscreen (LVTOPSUN BMS protection alarms)
LVTopsun Chg Diff_V error code
The voltage difference between the highest and lowest cell exceeded the BMS limit during charge.
Likely causes
- Ageing or mismatched cells
- Loose busbar or module interconnection
- Balancing not completed before the next charge
- Cell-voltage sense error
Checks to run, in order
- 1Read the cell spread on the Cell page before and during charge
- 2Check busbar torque and module interconnections
- 3Confirm the pack completes a full charge so balancing can run
- 4Compare spread between modules
Fixes
- Complete a full absorption charge so the BMS can balance
- Retorque the busbars to the manufacturer's value
- Replace a module whose spread stays high after balancing
When to escalate
If the spread exceeds the limit with torqued busbars and a completed balance cycle, ask the distributor to assess the module.
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 Chg Diff_V mean?
The voltage difference between the highest and lowest cell exceeded the BMS limit during charge.
How do I fix LVTopsun Chg Diff_V?
Complete a full absorption charge so the BMS can balance Retorque the busbars to the manufacturer's value Replace a module whose spread stays high after balancing
When should I escalate LVTopsun Chg Diff_V?
If the spread exceeds the limit with torqued busbars and a completed balance cycle, ask the distributor to assess the module.
Can I reset LVTopsun Chg Diff_V myself?
Only after isolating the AC and DC sides and running the checks above. If LVTopsun Chg Diff_V returns immediately, stop resetting it and escalate; a repeating fault usually points to a real circuit, battery or hardware problem.
Which models show LVTopsun Chg Diff_V?
LVTopsun Chg Diff_V 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