SolarEdge optimiser showing N/A — what's causing it and how it gets fixed
One or more optimisers in your SolarEdge monitoring portal are greyed out or showing N/A. It means those optimisers have stopped communicating with the inverter. This guide explains why it happens, how many panels it's costing you, and what the engineer will do to fix it.
Tell us how many optimisers are affected, whether it's one unit or a sequence, and share a monitoring portal screenshot if possible. We identify the specific unit and cause from portal data before any site visit.
Book optimiser diagnostic → All SolarEdge problemsOne N/A optimiser reduces output proportionally. Multiple N/A units in sequence usually means a string wiring fault, not individual failures.
SolarEdge optimisers send data back to the inverter over the DC power line (power line communication). When that signal stops — whether because the optimiser itself has failed, a connector has developed a fault, or a cable break has interrupted the communication chain — the monitoring portal marks that optimiser as N/A. It is a communication status, not a definitive failure verdict. A soft reset fixes some N/A faults. Others need on-site investigation to find the root cause.
How to diagnose SolarEdge optimiser N/A
Work through these in order. Steps 1–3 can be done from inside the house. If the fault doesn't resolve by step 4, an engineer is required.
Map which optimisers are N/A — pattern is everything
Log in to monitoring.solaredge.com and go to the layout view. Open SolarEdge Go on Bluetooth as well if you can, to cross-reference. In the layout view, greyed-out panels are the N/A optimisers. Note their positions carefully — the pattern tells you a lot before the engineer arrives:
Most likely a failed optimiser unit itself. Does not affect other panels. Check warranty status.
Communication chain broken at the first affected unit. Usually a connector, cable break, or one failed unit breaking the PLC chain.
Wider system or communications fault. Check whether the inverter is powered and whether any data at all is showing in the portal.
Take a screenshot of the layout view — the engineer will ask for this. If multiple N/A panels are not contiguous (scattered randomly), that may indicate individual unit failures rather than a chain break — useful information for the engineer.
Check SolarEdge Go for fault codes — P404 and P500-range
Open SolarEdge Go on your phone via Bluetooth. Stand within 3–4 metres of the inverter. Navigate to Alerts or the Device Status section. The codes to look for:
If you see P700 or P701 (Arc Fault Detected) alongside the N/A optimisers, stop here. That is a safety event and takes priority. See the arc fault detected guide before doing anything further.
If SolarEdge Go doesn't show a fault code for the N/A optimisers, note that down — it suggests the inverter has lost contact with the unit entirely rather than receiving an active fault report.
Check whether total system output has dropped — and by how much
In MySolarEdge, compare today's production chart to the same day type last week. If overall output has dropped by roughly the proportion of N/A optimisers (e.g. 2 of 16 panels = roughly 12% drop), the N/A units are contributing zero and the rest of the system is working normally. This confirms the fault is isolated to the affected optimisers and helps quantify the impact.
Divide the number of N/A optimisers by your total panel count. If you have 14 panels and 2 are N/A, you're losing approximately 14% of potential output on clear days. A single N/A panel on a 16-panel system costs roughly 6–7% of daily generation — about 2–3 kWh per sunny day depending on system size.
If the overall production drop is much larger than the proportion of N/A panels would explain, there may be an additional problem — a wiring fault affecting the whole string or a grid-side issue. Note this for the engineer.
Try a soft reset — AC isolator off for 60 seconds, then on
Before calling an engineer, try one soft reset. Go to your consumer unit and switch the solar PV circuit breaker (usually labelled "Solar PV", "SolarEdge", or "PV Inverter") to the OFF position. Wait 60 seconds. Switch it back on. Allow 10–15 minutes for the system to restart and the monitoring portal to refresh — SolarEdge monitoring can take up to 15 minutes to update after a restart.
The fault was likely a temporary communication glitch — perhaps caused by a brief power fluctuation or a firmware event. Monitor for recurrence over the next few days. If the N/A comes back, the fault is persistent and needs investigation.
The fault is persistent — either a failed optimiser, a damaged connector, or a broken DC string section. An on-site visit is required. Do not continue resetting.
Only attempt a soft reset if you have not seen a P700/P701 arc fault code. If there is any possibility of an AFCI event, do not restart the system — follow the arc fault guide instead.
Contact a qualified solar engineer with the pattern and fault codes
If the soft reset doesn't resolve the N/A, book an engineer. When you contact them, have ready:
The more detail you can provide, the better the engineer can plan the visit — reducing time on site and often allowing them to bring the correct replacement part in advance.
What causes SolarEdge optimisers to show N/A?
N/A appears for three distinct reasons. Understanding which applies to your system points the engineer to the right place on the roof.
Failed optimiser unit — most likely cause of a single N/A
SolarEdge power optimisers are electronic units mounted to each panel on the roof. Like any electronic component, they can fail — typically after 8–15 years, though early failures do occur. A completely failed optimiser stops communicating, and the monitoring portal marks it as N/A. The inverter loses visibility of that panel.
SolarEdge optimisers carry a 25-year manufacturer warranty. If the unit is confirmed as failed by an engineer within that period, it should be replaced under warranty. The engineer will confirm the serial number, document the fault with SolarEdge Go diagnostic data, and manage the warranty replacement process.
A single N/A panel that does not recover after reset, particularly if the panel is otherwise unshaded and the rest of the string is performing normally. Older systems (pre-2015 installs) have a higher incidence of individual optimiser failures — the early S250 and S270 series units are known to have had higher early failure rates.
MC4 connector fault — most likely cause of a consecutive run of N/A panels
SolarEdge optimisers pass their data signal along the DC power line from panel to panel back to the inverter. If an MC4 connector develops a fault — corrosion, physical damage, or poor original installation — it can break the communication chain. All optimisers from that point onwards lose communication and appear N/A, even though they are physically undamaged.
This is the most important diagnostic insight for consecutive N/A panels: the root cause is usually at or just before the first panel in the N/A run, not distributed across all the affected panels. A single faulty connector can produce 4, 6, or 8 N/A panels simultaneously.
Connectors at panel edges and string junction points are more exposed to UV and weather cycling. Connectors that were not fully locked at installation develop micro-resistance over years. Systems installed before 2018 on south-facing roofs in particular may have connectors approaching end-of-life.
DC cable damage — pest damage, abrasion, or UV degradation
DC string cables run from the roof array down to the inverter, often passing through the roof structure. Cable damage can break both the power circuit and the communication chain, causing N/A. Three failure modes are most common in UK installations:
What the engineer will do on site
SolarEdge's per-panel monitoring system means the engineer can usually narrow the fault to a specific panel, connector, or short cable section before going on the roof. Most N/A investigations are completed in a single visit.
The engineer will connect to the inverter via SolarEdge Go Bluetooth to pull the full fault log, optimiser communication status, and any P404 or P500-range codes. The layout view in SolarEdge Go, combined with the monitoring portal history, will show exactly which optimiser the communication chain broke at and when. This is done before any roof access.
The engineer will measure DC voltage at the inverter input and along the string. A lower-than-expected DC voltage or an open-circuit reading confirms a break in the string — caused by a failed optimiser, a connector, or a cable fault. The position of the voltage drop narrows the search zone on the roof.
With the fault location narrowed from Step 2, the engineer accesses the roof and physically inspects the connectors and cable in that section. All MC4 connectors in the affected area are tested for correct engagement, inspected for corrosion or cracking, and resistance-tested. If pest damage or cable abrasion is found, the engineer will check the full accessible cable run for further damage.
If a failed optimiser is identified, it is replaced — using the warranty process if within the 25-year warranty period. If a connector is faulty, it is replaced with a correctly-rated MC4 connector. After repair, the engineer will restart the system and confirm the affected optimisers re-appear in the monitoring portal and show expected output. A final DC string measurement is taken to confirm the repair.
How SolarEdge optimiser communication works — and why N/A happens
SolarEdge uses a distributed architecture where a power optimiser is attached to every panel. Each optimiser independently manages that panel's output — performing maximum power point tracking (MPPT) per panel rather than per string. This means shading on one panel does not drag down the rest of the string, which is the core advantage of the SolarEdge approach over traditional string inverters.
Communication between the optimisers and the inverter happens over the DC power line using power line communication (PLC). The optimisers form a daisy-chain: each unit relays data from the previous one towards the inverter. This is why a break at a single point in the chain — whether a failed connector, a damaged cable, or a failed optimiser — causes all subsequent units to appear as N/A. They are not necessarily failed; they have simply lost their communication route back to the inverter.
The monitoring portal displays this as N/A rather than a specific fault code because the inverter cannot receive any data from those optimisers — it doesn't know why they are silent, only that they are. SolarEdge Go provides more granular fault codes when you connect via Bluetooth directly to the inverter, which is why the engineer's first step is always a SolarEdge Go diagnostic session before any physical investigation.
SolarEdge's SafeDC feature, which reduces panel voltage to approximately 1V per panel when the system is shut down, applies to N/A scenarios as well. If the inverter shuts down or loses DC communication, the optimisers automatically reduce to SafeDC voltage. This means the roof is passively safe when the system is isolated — but DC cabling should still not be handled by anyone who is not a qualified electrician.
SolarEdge optimiser N/A — frequently asked questions
N/A means the inverter has lost communication with that optimiser. SolarEdge optimisers communicate over the DC power line (PLC) back to the inverter — when that signal stops, the monitoring portal marks the optimiser as N/A and stops reporting output data for that panel. The cause could be a failed optimiser, a faulty MC4 connector breaking the communication chain, a damaged cable, or a temporary glitch that clears on reset.
Yes. If a failed optimiser breaks the PLC communication chain, every optimiser after it in the string also goes N/A — even though those downstream units are physically functioning. This is why a block of 4, 6, or 8 consecutive N/A panels often has a single root cause at the start of the run. The engineer focuses investigation on the connector and cable at or just before the first affected panel, not on every N/A panel individually.
Yes — a failed or N/A optimiser reduces the system's output, which in turn reduces the electricity generated and potentially exported. On the Smart Export Guarantee (SEG), payments are based on actual metered export, so lower generation means lower export payments. On the older Feed-in Tariff (FiT), generation payments are typically based on deemed (estimated) generation, but lower actual output still affects the export element. Either way, an N/A optimiser is costing you money for every day it goes unrepaired.
Most N/A optimiser repairs are completed in a single half-day visit. The SolarEdge Go diagnostic session typically takes 20–30 minutes and narrows the fault to a specific panel or connector location. Physical access, inspection, and repair of a connector or optimiser replacement usually takes 1–2 hours on site. If the cause is widespread cable damage (such as significant rodent damage), the visit may extend to a full day. The engineer will provide an accurate time estimate once the SolarEdge Go diagnostic is complete.
SolarEdge power optimisers carry a 25-year manufacturer warranty. If the optimiser is confirmed as failed by an engineer within that period, the replacement unit should be covered. The warranty claim requires documentation: the serial number of the failed unit, SolarEdge Go fault data, and the engineer's diagnosis report. Labour costs for the site visit and installation of the replacement are typically not covered by the manufacturer warranty. An independent engineer can manage the warranty claim process on your behalf.
Other SolarEdge problems
P404 on individual optimisers or the full string — causes and engineer response.
P700/P701 safety event — isolation procedure and what the engineer will investigate.
System running but generating zero output — DC, AC, and firmware causes covered.
Steady or flashing red — what each LED pattern means and what to do.
SolarEdge optimiser N/A — let's get it diagnosed and back online.
Remote-first diagnosis from £75. We diagnose SolarEdge N/A faults using SolarEdge Go and on-site string testing. Whether it's a failed unit, a connector fault, or pest-damaged cabling, we identify the cause and carry out the repair in a single visit where possible.
This is a brand-specific version of our general system underperforming guide, which covers all brands.