- Solar and energy
- Solar inverter
301
Fronius inverter event 301
Risk level
High
Professional inspection is recommended.
Urgency
Immediate
Quick answer
Fronius defines event 301 as: The inverter detected AC overcurrent and briefly interrupted feed-in. The useful next discriminator is AC current by phase, export power and the event sequence. Preserve the event before any reset.
Safety first
Stop and check this first
- Do not change grid-code, voltage or frequency protection settings without installer and grid-operator authorization. Do not measure live boards yourself.
Safe checks you can perform
- Preserve the exact event context
- Collect one safe discriminator
- Respect the electrical stop point
Leave these tasks to a qualified professional
- Do not attempt this professional task: Measured handoff for Fronius 301
What a technician must be able to justify
A technician is coming
These are the steps they must carry out and show you. Tick them as they work: if steps are skipped, do not accept a part swap.
These are not instructions for opening or handling the equipment yourself. They are the checks that should support a technical conclusion.
Measured handoff for Fronius 301
What they doA qualified electrician should log phase voltages, frequency and connection-point impedance under the same export condition, then compare them with the active grid code and utility limits.
Before accepting a part or repair
Nothing has been shown yet. Do not accept a part swap based on the code alone.
Checks and evidence, step by step
Follow the documented order. An error code identifies the affected system, but it does not prove by itself which part has failed.
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Preserve the exact event context
No special tools
Procedure
Save event 301, timestamp, inverter model/serial, firmware, red-LED state, affected phase/string, power and weather before clearing anything.
Do not change grid-code, voltage or frequency protection settings without installer and grid-operator authorization. Do not measure live boards yourself.
Evidence: Fronius Symo / Eco status diagnostics
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Collect one safe discriminator
No special tools
Procedure
From the monitoring interface and a safe location, note whether other premises lost power and whether the event repeats at a particular export level or time. Record AC current by phase, export power and the event sequence; do not change multiple parameters or circuits at once.
Do not change grid-code, voltage or frequency protection settings without installer and grid-operator authorization. Do not measure live boards yourself.
Evidence: Fronius Symo / Eco status diagnostics
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Respect the electrical stop point
No special tools
Procedure
If supply to the site is abnormal, involve the grid operator; if only the inverter repeats the event, a qualified electrician must measure at the connection point.
Do not change grid-code, voltage or frequency protection settings without installer and grid-operator authorization. Do not measure live boards yourself.
Evidence: Fronius Symo / Eco status diagnostics
Where this code applies
A code is meaningful only inside the right product and version context.
Primary scope
- System
- Solar and energy
- Brand
- Fronius
- Product type
- Solar inverter
Known code variants
- 301 Dauerhaft verschoben
- 301 Déplacé définitivement
- 301 Moved Permanently
- 301 Movido permanentemente
- 301 Spostato definitivamente
- événement Fronius 301
- événement SMA 301
- evento Fronius 301
- evento SMA 301
- Fronius Ereignis 301
- Fronius event 301
- Fronius inverter 301
- Fronius Symo / Eco 301
- Fronius Wechselrichter 301
- HTTP 301
- HTTP status 301
- inversor Fronius 301
- inversor SMA 301
- inverter Fronius 301
- inverter SMA 301
- onduleur Fronius 301
- onduleur SMA 301
- SMA Ereignis 301
- SMA event 301
- SMA inverter 301
- SMA Wechselrichter 301
- Sunny Tripower X 301
What it means
Official meaning: The inverter detected AC overcurrent and briefly interrupted feed-in. Decision boundary: capture AC current by phase, export power and the event sequence. A qualified electrician should log phase voltages, frequency and connection-point impedance under the same export condition, then compare them with the active grid code and utility limits.
Warnings and stop conditions
- Highsource verified
Do not change grid-code, voltage or frequency protection settings without installer and grid-operator authorization. Do not measure live boards yourself.
Evidence: Fronius Symo / Eco status diagnostics
Symptoms and causes
Probable causes · in order
- What the Fronius event establishesConfirmed
The official Fronius Symo / Eco manual defines event 301: The inverter detected AC overcurrent and briefly interrupted feed-in.
Evidence: Fronius Symo / Eco status diagnostics
- The observation that changes the next branchPossible
Capture AC current by phase, export power and the event sequence. If supply to the site is abnormal, involve the grid operator; if only the inverter repeats the event, a qualified electrician must measure at the connection point.
Evidence: Fronius Symo / Eco status diagnostics
Virtual technician
Does 301 still appear after these checks?
Answer a few questions to narrow down the likely cause and the safest next action. Guidance only - it never replaces a professional.
Sources and technical references
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Fronius Symo / Eco status diagnostics
Fronius International GmbH · 2025 · official_doc
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