How do I fix Server Communication Loss (S_ERR) on a SolarEdge?

Check the router and internet connection. Then: Check inverter side connectors, Wi-Fi credentials and firewall after any router change.

SolarEdge

S_OK Lost

Server Communication Loss (S_ERR)

Inverter not communicating with SolarEdge monitoring. Production unaffected, monitoring and remote upgrades stop.

Common causes

Router or internet downWi-Fi password changedRJ45 or antenna looseTripped inverter AC breaker

What to check

STEP 1

Check the router and internet connection.

STEP 2

Check inverter side connectors, Wi-Fi credentials and firewall after any router change.

Escalate if

Connectivity verified but site still not reporting

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