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Your system is down or running degraded, but this is not an immediate safety danger. Work through the safe steps below.

SolarEdge Inverter 64 — What This Grid Fault Code Means

Error 64 on a SolarEdge inverter is a grid-protection shutdown, and its exact meaning depends on your inverter type. On three-phase inverters it means the AC voltage is too high on Line 1 (codes 64, 65 and 66 cover Lines 1, 2 and 3); on single-phase inverters it means the AC frequency is too high. In both cases the inverter has disconnected from the grid to protect itself, and it will reconnect automatically once grid conditions return to normal.

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?

What this code means

Your inverter may only feed power into the utility network while the grid's voltage and frequency stay inside strict limits set by your country's grid code. Error 64 means one of those limits was breached — so the inverter did what it was designed to do: it stopped producing and waited.

Which limit was breached depends on the inverter. On three-phase SolarEdge inverters running older firmware (CPU v3.18xx and earlier), error 64 means "AC Voltage Too High" on Line 1; 65 and 66 are the same fault on Lines 2 and 3 (newer firmware shows 8x1F, 8x20 and 8x21). SolarEdge attributes this to grid voltage above the country limit: check the country setting, verify actual AC grid voltage with the inverters off, use heavier-gauge AC cable for long runs, and consult the grid operator.

On single-phase SolarEdge inverters, codes 64–66 mean something different: "F-L1/L2/L3 Max," i.e. the AC frequency is too high (newer firmware shows 18x40–59/A–F). Frequency excursions are rarer than voltage excursions, but the inverter's response is the same: disconnect, wait through the reconnection timer, and resume automatically.

The key point for a homeowner: error 64 is almost never a sign that your inverter is broken. It is a symptom of grid conditions — most often high voltage during sunny midday hours when every rooftop system in the neighborhood is exporting at once.

What is this downtime costing you?

Rough estimate while your system isn't producing. Adjust the numbers to match your setup.

System size (kW) Peak sun hours / day Electricity rate ($/kWh)

–per day

–per week

–per 30 days

≈ – 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

['Grid voltage running high during peak solar hours — the most common cause. When many rooftop systems nearby export simultaneously, local voltage climbs, and the first inverter to hit its upper limit trips with error 64.', "Undersized or very long AC wiring between the inverter and the switchboard. Voltage rises along the cable under export (engineers call this voltage rise), so a long or thin cable run can push the inverter's terminals over the limit even when the street voltage is fine.", "The inverter's country or grid profile set incorrectly at commissioning, so it enforces the wrong voltage or frequency limits for your network.", 'A genuine grid frequency excursion (the single-phase meaning of 64) — uncommon, but networks can drift outside the permitted window briefly during switching events or disturbances.']

Safe steps to try

Work top to bottom, ticking off each step as you complete it. 0 of 1 done.

['Note the pattern first. Error 64 at midday on sunny days that clears by evening points to high grid voltage — not a broken inverter. Write down dates and times.', 'Check the AC voltage reading in the mySolarEdge app or monitoring portal around the time of the fault, if your system reports it.', 'Look at your switchboard: if the solar AC breaker has tripped, you may switch it back on once — but never force a breaker that trips repeatedly back on.', 'Perform one full power cycle: move the red P/1/0 switch to OFF, wait until the DC voltage falls to a safe level (or at least five minutes), then switch back ON and let the inverter complete its reconnection timer, which takes several minutes.', 'Do not change country settings, grid protection values, or any wiring yourself. If the code keeps returning, hand your log of dates and times to your installer.']

Is your inverter still under warranty?

Before paying for a repair, check — your installer may fix this free.

Brand Year installed

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

Call your solar installer if error 64 appears most sunny days, stays active for hours, or appears alongside other grid errors. An installer can verify the country setting, measure grid voltage at your switchboard, check the AC cable sizing, and raise it with the grid operator if the street voltage itself is the problem. Call a professional immediately — and do not reset again — if you notice a burning smell, discolored or hot wiring, or a breaker that trips again right after being reset. Only qualified personnel may open the inverter or adjust protection settings, and only where local regulations permit.

Frequently asked questions

Is error 64 dangerous?

No. It means your inverter's protection did its job by disconnecting from an out-of-spec grid. The risk is in ignoring repeated occurrences — chronic overvoltage stresses the inverter and your home's wiring, which is why persistent cases deserve an installer's visit.

Will error 64 clear by itself?

Usually, yes. Once the grid returns inside the permitted window, the inverter waits out its reconnection timer (several minutes, mandated by grid codes) and resumes production automatically — nothing to acknowledge or reset.

Why does error 64 only show up around midday?

Midday is when rooftop solar export peaks, and that export pushes local grid voltage up. If your street's voltage already sits near the upper limit, the extra push from every system exporting at once is enough to trip the most sensitive inverter. This midday pattern is the classic signature of a network voltage issue.

Can I raise the voltage limit so error 64 stops appearing?

Not yourself. Grid protection values must comply with your country's grid code, and changing them requires the right qualifications plus — in most regions — permission from local authorities or the grid operator. An installer can assess whether a change is appropriate and legal; a homeowner cannot.

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 — SolarEdge 'Troubleshooting SolarEdge Systems' Addendum (North America), MAN-01-00332-1.1, Error Codes table: three-phase CPU v3.18xx codes 64/65/66 (v3.19xx: 8x1F/8x20/8x21) = 'AC Voltage Too High (Line 1/2/3)'; and SolarEdge 'EV Charging Single Phase Inverter Installation Guide' MAN-01-00404-1.1, Appendix A: single-phase codes 64-66 (v3.19xx: 18x40-59/A-F) = 'F-L1/L2/L3 Max' (AC frequency too high).