SolarEdge error codes: 18xB5, 18xB7 and 18xBC explained

18xB5, 18xB7 and 18xBC are hardware faults inside the inverter. While one of them is showing, the inverter is not producing and there is no fix you can do yourself. SolarEdge’s instruction for all three is “Contact Support RMA related”, so the next step is a call to support, through your installer. 18xB5 and 18xB7 are a DC/AC in-stage overvoltage; 18xBC is a power module voltage imbalance. The only thing left for you to decide is how quickly you get the replacement moving.

SolarEdge error code format: what the four characters are telling you

From the official guide: “The Error Code consists of four hexadecimal characters, separated by the character x in the middle… For example: 03x85.” The x is a separator, not a hex digit, so “18x” is not a family prefix, and mistyped codes are common.

Two other things are worth knowing before you read any list:

• Warnings are a different namespace. “A warning message is identified by the word ‘Warning’ followed by a number.” The official warning list runs 1 to 7: 1, 2, 3, 4, 6 and 7 are fan failures, and 5 is raised when you try to open menus while the inverter is producing.
• Older firmware used plain decimal numbers for the same faults. SolarEdge’s North America troubleshooting addendum puts it plainly: “The error messages include an error number (in firmware version 3.18xx and before) or a code (in firmware version 3.19xx and later).” So error code 25 and 2x19 are the same fault on two firmware generations. If your inverter shows a bare two- or three-digit number, you are on the older notation, and the table further down maps the common ones across.

Codes appear on the inverter LCD on older units, and in the monitoring platform and mySolarEdge.

Is your SolarEdge inverter still producing?

For the 18x and 8x hardware codes, no: production has stopped. That is why the documented action is an RMA rather than a checklist.

Two codes in the 18x range are exceptions worth knowing, because they look alarming and are not:

• 18x3 is Night Mode: “an inverter status indicating that the input voltage is below 6V DC”. It is normal after sunset. If that is still what the screen says in the middle of the day, it is worth raising rather than shrugging off.
• 18x60 is the grid, not you: “Grid is down. When AC grid voltage returns the inverter will restart after the reconnection time”, with the official advice “If the problem persists, consult with the grid operator.”

Do not take the app’s word for whether you are producing. Go and read the hardware at midday on a bright day: the generation meter, or the kWh total on the inverter display. If that figure is moving, whatever you are looking at in the app is a monitoring problem (a “No communication with the Inverter” state in the monitoring platform rather than a production fault), and the offline-versus-not-producing triage is the page you want instead.

Self-clearing, OFF/ON reset, electrician, or RMA?

Sort your code into one of four buckets before you ring anybody.

Two of those, 8x56 and 8x18, are commercial three-phase codes and are rare on a domestic system.

The only documented reset in this family is the OFF/ON for the locked-device codes. There is no published reset that clears 18xB5, 18xB7 or 18xBC, and switching the inverter off and on repeatedly to make a red light go away is how a fault turns into a fault plus a week of lost production. Which is roughly how it goes:

here we are in the mist of the best production of the year to bank some excess, n on friday i check production on line at noon, n it says ‘zero’- lucky i was at the house, check the inverter, n the ‘fault’ lite is lit

The same owner, in the same thread, does the arithmetic himself: “i’m prob going to lose 11 days of banking around 40 per day… this sucks…” The figures and the currency are his own.

Who pays, and what to have ready before you ring

The warranty that applies to your unit is the one in your own paperwork: the certificate, the registered term and the installation contract, which vary by market, by product and by whether an extension was bought. Read those, and ask your installer in writing which of them they are working from.

What you can do is keep the call short. Have these to hand before you ring:

1. The inverter serial number, from the label on the case, not the model number.
2. The commissioning or installation date. This is the date most warranty questions turn on.
3. The exact code, character by character. 18xB5 and 18xB7 are different codes with identical official wording, and 18xBC is not 18xBF.
4. The last day the system produced normally, from the monitoring platform’s daily energy view. This is the number that decides how long the fault has been running, and it is the one nobody has ready.
5. A photo of the display or the LEDs, taken in daylight.

Arrive with a diagnosis rather than a symptom: the shorter the diagnostic visit, the less of it you are likely to be billed for.

And when the fault is real, the loss builds up during the wait:

We had solar panels fitted March 2019. The system has stopped working 3 times., I have lost about 2 months of generation last summer and it’s now not been working since April.

SolarEdge error codes list: what the official list actually contains

If your inverter shows a plain number instead, you are on the older firmware notation. The official mapping covers these:

SolarEdge isolation fault: legacy error 25, modern 2x19

Legacy error 25 is the isolation fault: the inverter stops until the insulation resistance recovers, which is why it appears on a damp morning and is gone by the time anyone looks. The same mechanism drives Growatt’s Error 203 on the MIN family, “PV Isolation Low”, which is code 125 on the 30-50K TL3-S, so the model family has to be named before a Growatt number means anything. The trouble is the intermittency: a fault that clears before you check is one nobody ever books an engineer for.

116 is “Common Voltage Too High” on three-phase inverters, not the “DC charged” meaning that circulates for it.

SolarEdge fault light, red light, S_OK and P_OK: reading the inverter itself

On the older LCD generation the initial status screen renders as:

Vac[V]  Vdc[V]  Pac[W]
P_OK: XXX/YYY   <S_OK>
----------  ON

Two strings on that line answer two different questions: one is about the connection to SolarEdge, the other about the optimisers.

• S_OK: “The connection to the SolarEdge monitoring portal is successful (appears only if the inverter is connected to the server).” Its absence means the inverter is not reaching SolarEdge. That is a communication fault. Production may be perfectly fine.
• P_OK: XXX/YYY: “There is a connection to the power optimizers and at least one power optimizer is sending monitoring data. XXX is the number of power optimizers for which telemetries have been received in the last two hours. YYY is the number of paired power optimizers identified during the most recent pairing process. If XXX and YYY are not equal, there may be a problem in one or more power optimizers.” So a mismatch between the two numbers points at the panel level, not at the inverter or your Wi-Fi.

On the HD-Wave and SetApp generation there is no LCD, and the three LEDs carry it instead. From the official LED page: “Blue ON - the inverter is communicating with the monitoring platform”, “Green ON - the system is producing”, “Green blinking - AC is connected but the system is not producing”, “Red ON - system error”. The blue LED is the S_OK indicator in another form, so green on with blue off is a system producing perfectly and telling nobody.

The documentation also defines its flash patterns: “Blinking = Turns ON and OFF for the same duration”, “Flickering = Turns ON for 100 mS and turns OFF for 5 seconds”. Green flickering is night mode; green blinking is not.

A red light and a healthy-looking app can coexist, and the fault can be lit up on the wall while the portal says nothing at all. That is how the “faulty AC relay” story below starts:

Went into the garage, all green lights - checked the display and saw output at zero :eek: No errors reported on panel or on monitoring portal. … inverter boots then red lights and Error Code 26 Faulty AC Relay appears on screen - oh poo

Error 26 is the poster’s own screen from 2017; the older numbers SolarEdge still maps include 13, 25, 114, 115, 116, 120, 121 and 150. On the current list, the relay fault is 2xB5, “Relay feedback”, action “Contact Support RMA”.

SolarEdge 18xBF, 18x86 and 8xB7: codes not in the official list

None of these five appears in SolarEdge’s official documents. Each has a real neighbour you probably meant, which is worth knowing before you quote support a code they cannot look up.

Three more turn up too. 8xB7 does not exist on its own (the 8x range ends at 8x8C) and is a truncation of 18xB7. 18x86 is not there either: the 18x range stops at 18x71 before resuming at 18xB5. Bare 2xB is not a code at all; the real ones nearby are 2xB5, relay feedback, and 3xB, no country selected.

119 is absent from the official mapping table (114, 115, 116, 120 and 121 are listed, 117 to 119 are not), so the “119 init” reading that circulates has nothing official behind it. And 500 appears on no SolarEdge list we could find; if you see it in a browser rather than on the inverter, check whether it came from the monitoring portal rather than from your equipment.

If none of the above matches what is on your screen, photograph the screen and read the characters off the photograph. B5 and B6, C and 0, 6A and 6B are all one glance apart on a small LCD in a dark garage.

Nobody may be emailing you about this

Whether an 18xB7 costs you a week or a season depends on whether anyone is told. SolarEdge’s alerts are built for installers, to resolve issues across their fleets. Four things follow:

• The alert rules are not yours. Only the account manager or admin can create, edit or enable one; as the homeowner you cannot.
• Your e-mail address sits behind a permission your installer controls: Admin, Site Access, then the toggle “Expose to alerts notifications”. If that installer is no longer trading, the account itself is the first problem: your solar panel company has gone bust.
• Silence is not detected quickly. “No communication with the Inverter” only triggers after at least three hours without contact, and by default arrives in a daily roll-up; immediate delivery is a separate opt-in.
• There is no underperformance alert at all. Nothing in SolarEdge’s alert list compares your output against what the weather says you should have made. The production alerts that do exist are hard faults: “Production issue – inverter overheated” and “String is not producing”.

So a hard code like 18xB5 may reach you, if your installer enabled that rule in the profile assigned to your site and ticked your permission. And a system that is up, communicating, and quietly making less than it should raises nothing, ever. One owner put the difference this way:

my SE 5000H inverter failed last summer (15 months from install) so a bit easier to spot when production fell off a cliff.

A total failure is the easy case to spot. The partial one (one string, one optimiser) is the one you find on a bill.