Communication Failures — Field Documentation¶
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Communication failures are the most common category of "false alarm" service calls — the system is producing power, but monitoring is offline. Understanding communication architecture helps diagnose these quickly.
Key Principle¶
Communications ≠ Production
A site that shows "offline" in the monitoring portal may still be producing at 100%. Loss of monitoring is annoying and should be fixed, but it is almost never an emergency.
Always check whether the inverter display shows active production before assuming a production loss.
Common Communication Failure Patterns¶
Pattern 1 — Wi-Fi Credential Change¶
Symptom: Site offline since a specific date (often when client changed router or got new internet service)
Diagnosis: Check "last communication" timestamp in portal — matches ISP/router change? Ask client.
Resolution: Re-enter Wi-Fi credentials via SolarEdge GO (current) or SetApp (legacy SolarEdge), or manufacturer app for other platforms.
Pattern 2 — RS485 Bus Break¶
Symptom: Some inverters online, some offline. Offline units are typically at the "far end" of the chain.
Diagnosis: RS485 daisy-chain break — the chain fails at the break point, taking all downstream inverters with it.
Resolution: Trace the RS485 chain, find the break (connector, damaged cable, reversed polarity at a junction).
Pattern 3 — Cellular Kit Lost Signal¶
Symptom: Site offline intermittently, or offline after a specific weather event.
Diagnosis: Check cellular signal quality at inverter location. Check if SIM is active and data account is current.
Resolution: Verify cellular signal, check SIM account status, relocate antenna if possible.
Pattern 4 — Gateway Offline (Microinverter)¶
Symptom: All microinverters show offline. System may still be producing.
Diagnosis: Gateway (Envoy, ECU) lost power or lost internet connectivity.
Resolution: Power cycle gateway, check network connection, re-enter Wi-Fi if needed.
Pattern 5 — RS485 Polarity Reversal¶
Symptom: RS485 bus not communicating at all after installation or wiring work.
Diagnosis: A and B wires are reversed on the bus.
Resolution: Swap A and B wires at one end of the problematic segment.
Documented Cases¶
Specific site cases to be documented here.