SolarEdge · PV inverters · SolarEdge SE3K–SE10K (three-phase inverter with power optimizers, SetApp)
Error 18x3Night Mode is an inverter status indicating that the input voltage is below 6V DC.
Name in the manufacturer's documentation (fault list): Night Mode is an inverter status indicating that the input voltage is below 6V DC.
[1]
In plain words (editorial)
Night mode: a status, not a fault – the DC input voltage from the panels is below 6 V, as happens at night. If it appears in daylight, the manual says the DC side should be tested.
When to call a service technician: If it appears in daylight, contact your installer.
✎ editorial – written from the cited sources, not a manufacturer statement. Status: draft.
For technicians
Steps given by the manufacturer (source text)
- Test the DC side and contact support for further guidance[2]
⚠ Work on refrigerant circuits, mains electricity and PV DC wiring is for qualified technicians only.
The Polish page has more detail (plain-language explanation, safe checks, guides): Read in Polish →
Sources
Every statement has a footnote to the document and PDF page. “Quote verified” means the quote was found automatically in the text of that page.
- [1] SolarEdge Inverters Error Codes and Troubleshooting – User Guide (Version 1.2, 2026-09) (se-inverter-installation-guide-error-codes (v1.2)) , p. 17 official manufacturer document quote verified
18x3 Night Mode is an inverter status
- [2] SolarEdge Inverters Error Codes and Troubleshooting – User Guide (Version 1.2, 2026-09) (se-inverter-installation-guide-error-codes (v1.2)) , p. 17 official manufacturer document quote verified
Test the DC side and contact support for further guidance