The light burns all day.
Learning Track · Module 7: Failure library · Step 47 of 101
| Symptom | The light or the full circuit stays on in daylight. Energy is high every day. |
|---|---|
| Cause | The photocell relay is welded closed, the sensor window is covered, or water entered the photocell. |
| Check | Cover the photocell in daylight: the state must not change if it is stuck. Compare switch-off time with sunrise in the data. |
| Fix | Replace the photocell. On a cabinet, also check the contactor. |
| Prevent | Use fail-off photocells where permitted. Use an astronomical clock at the cabinet. Alarm on daylight burning. |
Sources
- IEC 60364-6 Verification of low-voltage installations
- IEC 61643-11 Surge protective devices
- IEC 60598-2-3 Luminaires for road and street lighting
- Maker installation and maintenance instructions
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