Fail_Safe: Fail Safe

The "Fail Safe" error indicates that the inverter has activated a protective mechanism to prevent potential damage or hazards. This error typically occurs when the inverter detects an abnormal operating condition that could compromise its safety or the safety of the connected electrical system.

Why it's problematic

The fail-safe mode shuts down the inverter, halting solar energy production and interrupting power supply if battery backup is unavailable.
It often signals an underlying problem that requires investigation and resolution.

Possible causes

Over-temperature: The inverter may have exceeded its safe operating temperature due to inadequate ventilation, high ambient temperatures, or a cooling system malfunction.
Ground Fault: A current leak to the ground can trigger the fail-safe mechanism to prevent electrical shock hazards.
Short Circuit: A short circuit in the DC or AC wiring can cause excessive current flow, activating the fail-safe protection.
Internal Component Failure: A malfunctioning component within the inverter, such as a sensor, relay, or power electronic device, can trigger a fail-safe shutdown.

Before you begin

Safety First: Working with electrical equipment always involves risks. Ensure you are qualified and follow appropriate safety precautions. Disconnect the inverter from both AC and DC sources before performing any physical inspection or adjustments.

Gather Information: Before starting troubleshooting, have the inverter manual on hand. You should also gather information about the inverter model and serial number, the installation date, and the PV array configuration (number of panels, capacity, and number of strings).

Troubleshooting steps

Check for Over-temperature: Inspect the inverter's surroundings and ensure adequate ventilation. Verify that the cooling fans are operational and that the inverter is not exposed to direct sunlight or other heat sources.
Inspect Wiring for Short Circuits: Carefully examine the DC and AC wiring connections for any signs of damage, loose connections, or exposed conductors that could cause a short circuit.
Check Grounding: Ensure that the inverter is properly grounded according to local electrical codes and manufacturer's instructions. Use a clamp meter to check for current flow on the ground conductor.
Restart the Inverter: After addressing any identified issues, attempt to restart the inverter. If the fail-safe condition has cleared, the inverter should resume normal operation.
Check Inverter Display: If the error persists, check the inverter's display for specific error codes or messages that could provide further insights into the cause of the fail-safe activation.

Verifying the solution

The resolution of the "Fail Safe" error will be confirmed by the inverter resuming normal operation. This typically involves the inverter restarting and beginning to generate power or passing through to battery power if available. The inverter's display should no longer show the "Fail Safe" error message, and the associated LED indicator lights should reflect normal status.

If the problem is not resolved

If the error persists after following all the above steps, there might be an internal fault within the inverter.

As a system owner: In this case, contact the inverter installer or distributor for further assistance. You can find the details of your installer in the MyAutarco app.
As a certified installer: Contact Autarco Support; you can submit a support case via Helios.