<!– –>{ “@context”: “https://schema.org”, “@graph”: [ { “@type”: “Article”, “headline”: “Solar System Not Producing — Causes and Fixes”, “description”: “Solar panels and inverter installed but generating zero or near-zero output? This guide covers every common reason a solar system stops producing electricity — and how to diagnose each one.”, “url”: “https://solar-tech-support.co.uk/problems/system-not-producing/”, “datePublished”: “2026-03-18”, “dateModified”: “2026-03-18”, “author”: { “@type”: “Organization”, “name”: “STS Solar Tech Support”, “url”: “https://solar-tech-support.co.uk” }, “publisher”: { “@type”: “Organization”, “name”: “STS Solar Tech Support”, “url”: “https://solar-tech-support.co.uk” } }, { “@type”: “HowTo”, “name”: “How to diagnose a solar system not producing electricity”, “description”: “A systematic process to identify why a solar system is generating zero or near-zero output — covering inverter state, isolation switches, fault codes, and grid connection.”, “url”: “https://solar-tech-support.co.uk/problems/system-not-producing/”, “step”: [ { “@type”: “HowToStep”, “name”: “Confirm whether the inverter has power and is displaying anything”, “text”: “Go to the inverter and look at its display and status lights. If it is completely dark with no lights at all, the problem is upstream of the inverter — either no AC power, a tripped MCB, or a DC isolator in the off position. If the inverter is showing a fault code or red light, start with the fault code diagnosis. If it appears to be running normally but the portal shows zero generation, the issue may be a portal or monitoring fault rather than a generation fault.” }, { “@type”: “HowToStep”, “name”: “Check all isolation switches are in the correct position”, “text”: “Visually check: the AC solar isolator (usually near the consumer unit), the DC solar isolator (usually on or near the inverter), and any battery isolator if present. All should be in the ON or I position. An inadvertently switched-off isolator — after maintenance, a power cut, or tampering — is a simple cause of total zero generation.” }, { “@type”: “HowToStep”, “name”: “Check whether a circuit breaker has tripped in the consumer unit”, “text”: “Open the consumer unit and look for any tripped MCBs or RCDs associated with the solar system — typically labelled ‘Solar’, ‘PV’, or similar. A tripped breaker will be in the mid or down position. Reset it once. If it trips again immediately, there is a fault in the circuit and an electrician should investigate before further resets.” }, { “@type”: “HowToStep”, “name”: “Check the monitoring portal for fault codes and event history”, “text”: “Open your monitoring portal and check the event log for fault codes. Note when generation last showed any output. Check whether the portal itself is showing ‘offline’ or ‘device not connected’ — if the monitoring is offline, the system may be generating but the data is not reaching the portal. Compare the portal reading against the inverter display’s live generation figure.” }, { “@type”: “HowToStep”, “name”: “Check the inverter display’s live generation figure directly”, “text”: “The inverter display shows a live AC output power figure in watts. On a clear sunny day a correctly operating system should show significant output — a 4kW system might show 2,000–3,500W in good midday conditions. If the display shows 0W or a very low figure despite good sunlight, and no fault code is shown, the issue is likely a DC-side problem — panels, string cabling, or DC string fuses.” } ] }, { “@type”: “FAQPage”, “mainEntity”: [ { “@type”: “Question”, “name”: “Why is my solar system showing zero generation?”, “acceptedAnswer”: { “@type”: “Answer”, “text”: “Zero generation is caused by one of: inverter completely off or in fault state; AC isolation switch turned off; tripped MCB in consumer unit; DC isolation switch off; severe DC-side fault (string short, fuse blown, panel damage); or a monitoring fault where the system is actually generating but data isn’t reaching the portal. Check the inverter display first — it will tell you whether the inverter itself is running.” } }, { “@type”: “Question”, “name”: “Could my solar system be generating without me knowing?”, “acceptedAnswer”: { “@type”: “Answer”, “text”: “Yes — if your monitoring dongle has lost WiFi connection, the portal will show the device as offline and display zero generation, but the inverter may be working normally. Check the inverter display directly for a live generation figure. If it shows a positive wattage, the system is generating — you just have a monitoring connectivity issue, not a generation fault.” } }, { “@type”: “Question”, “name”: “My solar was working and then suddenly stopped — what happened?”, “acceptedAnswer”: { “@type”: “Answer”, “text”: “Sudden cessation of generation is usually caused by: the inverter tripping on a fault (check the display for a fault code); an AC or DC isolation switch being turned off; an MCB tripping; or a grid disturbance that caused the inverter to disconnect and fail to auto-reconnect. Check the consumer unit for tripped breakers and the inverter display for fault codes.” } }, { “@type”: “Question”, “name”: “Is zero generation always a serious fault?”, “acceptedAnswer”: { “@type”: “Answer”, “text”: “Not always. A switched-off isolation switch or tripped MCB causes total zero generation but is trivially easy to fix. However, zero generation caused by an arc fault, string short circuit, or inverter hardware failure is a more serious issue that requires professional investigation. The fault code tells you which category you are in.” } }, { “@type”: “Question”, “name”: “Can bad weather cause zero generation?”, “acceptedAnswer”: { “@type”: “Answer”, “text”: “Very low generation in poor weather is normal — a heavily overcast winter day may produce less than 5% of peak rated output. True zero on a sunny day is always a fault. If the generation figure in the portal is very low but not zero, check whether the weather conditions actually justify it before investigating further.” } } ] }, { “@type”: “BreadcrumbList”, “itemListElement”: [ { “@type”: “ListItem”, “position”: 1, “name”: “Home”, “item”: “https://solar-tech-support.co.uk/” }, { “@type”: “ListItem”, “position”: 2, “name”: “Problems”, “item”: “https://solar-tech-support.co.uk/problems/” }, { “@type”: “ListItem”, “position”: 3, “name”: “System Not Producing”, “item”: “https://solar-tech-support.co.uk/problems/system-not-producing/” } ] } ]}
System fault · All setups
Solar system not producing electricity
Panels are on the roof, inverter is installed, but generation is showing zero — or something close to it. The portal shows nothing. The inverter display may be blank or showing a fault.
Before calling an engineer, work through the basic checks below. A significant number of zero-generation calls turn out to be a switched-off isolator or a tripped breaker.
Check the basics before calling an engineerFault code guides the diagnosisMonitoring offline ≠ not generating
Can’t find the cause?
A remote diagnostic session reviews the event log, portal data, and system configuration to identify the cause and tell you whether it needs an engineer on site or can be fixed remotely.
First: check the inverter display directly. If the monitoring portal shows zero but the inverter display shows a live generation figure in watts, your system is generating — you have a monitoring connectivity issue, not a generation fault. See monitoring offline.
Why a system stops producing
Starting with the most common and easiest to fix.
Isolation switch turned off
AC or DC isolator switched off — after a maintenance visit, a power cut, or accidentally. Easiest fix: check all accessible switches and turn back on.
MCB tripped in consumer unit
The solar MCB or RCD in the consumer unit has tripped. Reset it once — if it trips again immediately there is an underlying fault.
Inverter fault trip
The inverter has tripped on a fault and is showing a red light or fault code. Find the code, understand what it means, then decide whether a single reset is appropriate. See inverter red light.
Grid disconnection or outage
If the grid supply is absent or outside limits, the inverter disconnects and stops generating (G98/G99 compliance). Generation resumes automatically when the grid returns. Check whether your house has any power at all.
DC string fault
A blown DC fuse, open-circuit string, or failed panel is preventing solar energy from reaching the inverter. The inverter may show no fault — it simply has no DC input to convert.
Inverter hardware failure
Less common. The inverter itself has failed — from age, power surge, or component failure. Usually shows a persistent fault code that doesn’t clear with reset. Requires engineer diagnosis.
How to diagnose zero generation
Work through these in order on a day with at least some sunlight.
1
Check the inverter display and status lights
Go to the inverter physically and check its display. If there is a fault code visible, that is your starting point. If there is no display at all — completely dark — the inverter has no AC power. If it looks normal and shows output wattage, but the portal shows zero, you have a monitoring issue rather than a generation fault.
2
Check all isolation switches
Locate and visually check: the AC solar isolator (usually a red rotary switch near the consumer unit), the DC solar isolator (on or near the inverter, often labelled DC ISOLATOR or PV ISOLATOR), and any battery isolator. All should be in the ON position. Switches can be knocked off accidentally during maintenance or by curious visitors.
3
Check the consumer unit for tripped breakers
Open the consumer unit and look for any MCB or RCD that has tripped (in the mid or down position). Solar circuits are usually labelled. Reset any tripped breaker — if it trips again immediately, do not force it back on. Call an electrician.
4
Check the portal event log
Open your monitoring portal and look at the event log. Find when generation last showed any output and what events occurred around that time. Fault codes, firmware update events, and connectivity losses are all logged and will point you towards the cause.
5
If all looks normal — check AC voltage at the output
If the isolators are all on, there are no tripped breakers, the inverter display looks normal, but generation is still zero, the issue is likely a DC-side problem — no solar energy reaching the inverter from the panels. This could be a blown DC string fuse, open-circuit string cable, or panel-level fault. This requires engineer investigation to diagnose safely.
Brand-specific zero-generation checks
Some brands have system modes or monitoring quirks that make a system appear to not be producing when generation is actually occurring. Check the note for your brand first.
GivEnergy
GivEnergy hybrid inverters have a Backup-Only mode that prevents grid export and can make the system appear to not produce to the grid — but solar is still generating and charging the battery. Check the System Mode setting in the GivEnergy portal before concluding zero generation. See the GivEnergy hub for portal navigation.
Growatt
Growatt hybrid inverters have a “Battery First” power priority mode that suppresses solar export in the monitoring app even when the PV is generating. Also, Growatt ShineWiFi dongles drop cloud connection regularly — always verify the inverter display shows live generation data before concluding zero output.
Sunsynk / Deye
Sunsynk inverters can enter a latched fault state after a sustained grid event, displaying zero export figures even after supply is restored. A controlled restart — AC isolation off, DC isolation off, wait 2 minutes, restore in reverse order — typically clears this state. If the fault recurs, log the event code from the Settings > Fault Log menu.
Check in this order: (1) the inverter display for fault codes; (2) all isolation switches are on; (3) no MCBs have tripped in the consumer unit; (4) the portal event log for when and why generation stopped. In a significant number of cases it is a switched-off isolator or tripped breaker — simple to fix without an engineer.
Yes — check the inverter display directly. If it shows a live generation figure in watts, your system is generating and the portal offline status is a monitoring connectivity issue. See the monitoring offline page for that fault.
Sudden cessation is usually caused by an inverter fault trip (check the display for a fault code), a switched-off isolator, a tripped MCB, or a grid disturbance that caused the inverter to disconnect. Check the consumer unit and inverter display first, then the portal event log for the exact time and cause.
Very heavy overcast conditions can reduce generation to near-zero — especially in winter. True zero on a sunny day is always a fault. If you’re unsure whether weather is the cause, check historical data: on a similar day last week or last year, what was the system producing?
Worked through the checks and still not generating?
If the basics are all correct but generation is still zero, a remote diagnostic session can review the full event log and system data to pinpoint the cause — and tell you whether it needs an engineer visit.
