Most failures show in the data first.
Learning Track · Module 5: Solar street lights · Step 37 of 101
| What you see | Likely cause |
|---|---|
| Light goes off before morning, more each week | Battery capacity is falling |
| Low charge on sunny days | Dirty or shaded panel, loose panel cable, controller fault |
| Battery full but light off | LED, driver, or controller load output |
| Whole unit offline suddenly | Theft or vandalism |
| Light on in the day | Panel voltage sensing fault (the panel acts as the light sensor) |
What to monitor
- Battery state of charge at dawn: low values show the system is undersized or ageing.
- Daily solar charge (Wh): compare with nearby units to find dirty or shaded panels.
- Hours of light each night against the schedule.
- Battery temperature.
Many solar controllers now report by NB-IoT, LTE-M, or LoRaWAN. OpenSLMS treats a solar light as any other asset: alarms raise work orders, and patrols and preventive plans work the same way.
Sources
- IEC 62124 Photovoltaic stand-alone systems: design verification
- IEC 62509 Battery charge controllers for PV systems: performance
- IEC 62619 Safety requirements for secondary lithium cells and batteries for industrial applications
- IEC 61215 and IEC 61730 PV module performance and safety
Changes: 30 October 2026: First publication: guides for Europe, the Middle East, South Asia, and the USA; failure library; tender clause library; comparisons; tools; downloads. See the changelog. Found a mistake? Report it.