HESP series hybrid inverters (single-phase 4-12 kW and three-phase 8-12 kW)
SRNE 09 error code
PV overvoltage protection (PvVoltHigh): the PV input voltage exceeded the maximum allowed and PV boosting stopped.
Likely causes
- PV string open-circuit voltage above the inverter maximum at low temperature
- Too many modules in series for the 230 V HESP input window
- Wrong string wiring after a reconfiguration
- PV surge during lightning
Checks to run, in order
- 1Measure the string open-circuit voltage at the DC input with a multimeter
- 2Compare it with the maximum PV input voltage on the inverter datasheet
- 3Recalculate string Voc at the coldest expected site temperature
- 4Check the DC isolator and connectors for damage
Fixes
- Disconnect the string and reconfigure it to fewer modules per string
- Restart the inverter after the PV voltage is within the window
- Replace damaged DC connectors or surge devices
When to escalate
If the measured Voc is comfortably inside the window and the fault still appears, the PV voltage sensing circuit needs distributor attention.
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 SRNE 09 mean?
PV overvoltage protection (PvVoltHigh): the PV input voltage exceeded the maximum allowed and PV boosting stopped.
How do I fix SRNE 09?
Disconnect the string and reconfigure it to fewer modules per string Restart the inverter after the PV voltage is within the window Replace damaged DC connectors or surge devices
When should I escalate SRNE 09?
If the measured Voc is comfortably inside the window and the fault still appears, the PV voltage sensing circuit needs distributor attention.
Can I reset SRNE 09 myself?
Only after isolating the AC and DC sides and running the checks above. If SRNE 09 returns immediately, stop resetting it and escalate; a repeating fault usually points to a real circuit, battery or hardware problem.
Which models show SRNE 09?
SRNE 09 is documented for HESP series hybrid inverters (single-phase 4-12 kW and three-phase 8-12 kW). Confirm the code on your own unit's display or manual before ordering parts.
More SRNE error codes
- SRNE 01Battery undervoltage alarm: the battery voltage has fallen below the [Batt. Under volt. alarm] value under Battery Setup, and the alarm does not by itself stop the output.
- SRNE 02Battery discharge average current overcurrent, detected by software (BatOverCurrSw); the inverter limits or stops discharge.
- SRNE 03Battery not connected (BatOpen): the inverter cannot see a battery on the DC side and stops the output.
- SRNE 04Battery undervoltage stop-discharge (BatLowEod): the battery has reached the low-voltage cut-off and the inverter has stopped discharging.
- SRNE 05Battery overcurrent detected by hardware protection (BatOverCurrHw); the inverter shuts the output down.
- SRNE 06Charging overvoltage protection (BatOverVolt): battery voltage rose above the over-voltage cut-off and charging was stopped.
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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