Warning What does this mean?
Your system is down or running degraded, but this is not an immediate safety danger. Work through the safe steps below.
Sungrow Inverter Code 100 — What the Hardware Overcurrent Fault Means
Code 100 is an inverter overcurrent hardware fault — the current inside your Sungrow inverter rose above its hardware protection value, so it shut down to protect its power electronics. Sungrow says this is generally caused by abnormal fluctuations on the power grid. This is not a homeowner-fixable fault: the inverter’s fault recording needs to be downloaded and sent to Sungrow technical support for analysis.
What should I do first?
Two quick questions — we'll point you to the right starting point.
Is this code still showing on your inverter's display?
Is your system producing power right now?
What this code means
Every inverter has two layers of current protection. The first is software: the control system watches the current and backs off or disconnects when it approaches the design limits. The second is hardware: fast-acting circuits that trip when the current crosses an absolute ceiling, faster than software can react. Code 100 means the second layer fired — the current genuinely exceeded what the hardware is built to survive, and the inverter stopped immediately to save its power stage.
Sungrow’s own fault description is short and honest about the cause: the reason is generally that the power grid has abnormal fluctuations. A grid voltage sag, swell, or phase disturbance can drive a surge of current through the inverter’s output stage before the control system can respond. Lightning-induced surges and utility switching events are the usual suspects.
What code 100 is NOT is a settings problem you can tune away, or a panel problem. It is an internal protection event, and the correct response is diagnostic, not operational: capture the fault recording and let Sungrow’s engineers read it. That is why the official troubleshooting step is to download the fault recording and provide it to Sungrow technical support for further analysis — the recording shows exactly what the voltages and currents were doing in the moments before the trip, which is what distinguishes a grid event from a developing hardware problem.
What is this downtime costing you?
Rough estimate while your system isn't producing. Adjust the numbers to match your setup.
≈ – kWh of lost production per day.
Estimate only — assumes ~80% real-world output vs. nameplate. Actual losses depend on weather, shading, panel direction, and your tariff.
Common causes
- ['Abnormal fluctuations on the power grid — voltage sags, swells, or phase disturbances that drive a current surge through the inverter (Sungrow stated usual cause).', 'Lightning-induced surges on the grid, even from distant strikes.', 'A sudden large load switching on or off nearby — on your property or the local network.', 'Utility switching operations or a grid fault upstream of your property.', 'Degraded internal power components — aging IGBTs or drifting current sensors (rare, and only diagnosable from the fault recording).']
Safe steps to try
Work top to bottom, ticking off each step as you complete it. 0 of 1 done.
Is your inverter still under warranty?
Before paying for a repair, check — your installer may fix this free.
Based on typical standard warranty terms — always confirm with your warranty card or installer paperwork, as terms vary by model, region, and purchase date.
When to call an electrician
Contact your solar installer right away. For code 100, Sungrow’s documented procedure is to download the inverter’s fault recording and send it to Sungrow technical support for analysis — your installer will do this and liaise with Sungrow on what it shows. If the recording points to a grid event, the system can usually go back into service with monitoring; if it points to the inverter’s own power stage, the unit needs professional repair or replacement. Do not keep restarting the inverter to work around a recurring code 100.
Frequently asked questions
Is code 100 the same as code 006 or 007?
They are all overcurrent-related, but different layers: 006 is AC output overcurrent handled by the control system, 007 is a transient the inverter recovers from by itself, and 100 is the hardware protection layer tripping — the most serious of the three.
Can a power surge from the grid really cause this?
Yes — it is Sungrow’s own stated usual cause. The grid does not have to fail outright; a sharp fluctuation is enough to push current past the hardware limit for an instant.
Will my inverter be damaged?
The hardware trip exists precisely to prevent damage, and it usually succeeds. But a code 100 means the inverter experienced a genuine overcurrent event, so the fault recording should be checked rather than assumed harmless.
How long does the Sungrow analysis take?
It varies — your installer sends the recording to Sungrow technical support, who examine the pre-trip waveforms. Ask your installer for a timeline; meanwhile, do not run the system in a fault-retry loop.
Need a professional?
This fault may need professional diagnosis. Contact a qualified solar electrician in your area.
Sources: meaning and troubleshooting verified against the manufacturer's documentation — Academy of Sungrow Distribution Europe (academy.sungrow-emea.com) — ‘Fault code and troubleshooting steps of SHxxRS 100-110’: Code 100 ‘Inverter overcurrent hardware fault’ (inverter current higher than hardware protection value; generally caused by abnormal grid fluctuations; fault recording to Sungrow technical support)