No data is not the same as no light.
Learning Track · Module 6: Faults · Step 41 of 101
- Many stop together: usually a power cut or network outage.
- One stops, neighbours report: supply, control breaker, SIM, antenna, or a failed device at that site.
- Reports at night but not in the day: its power is on the switched side of the contactor. Move it to the unswitched side.
Related across the playbook: Node offline: The light may work, but the data stopped.
Sources
- IEC 60364-6 Verification of low-voltage installations
- IEC 61643-11 Surge protective devices
- Maker installation and maintenance instructions
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