01442 220 100

Solar Inverter Error Codes

November 3, 2020

For the most part, solar PV arrays are fairly simple and straightforward systems.

They are the coming together of three main-components:
  • Solar Panels (known in the industry as modules)
  • Inverters (these invert the solar energy from DC into AC)
  • Mounting System (the aluminium frame that anchors the solar modules to your roof)

Beautifully Simple

The beauty of solar PV compared to other forms of renewable energy, such as wind turbines for example, is that there are no moving parts.
This means that – providing the system was installed correctly in the first place – you are unlikely to have any sort of mechanical breakdown of the array.
That said, solar PV systems are like any other electrical installation; no matter what you do, things can and do go wrong.
The main point of failure in a solar installation is the inverter; the inverter is arguably the most important part of the whole array, and the part of the system that does the most work.
Thankfully, if something does go wrong with your inverter, they are designed to give you a clue as to what the issue is as almost all inverters have a small, integrated, LED screen that will provide the owner with key bits of data on instantaneous production, historical production and system status.
If your system were to stop working, the first thing you would probably notice is that the green light on the front of the inverter is now either red or amber. These system lights work much like a traffic light system: green is on, red is off and amber suggests there has been or is, an issue with the system.
If you notice that your array is showing a red or amber light, the next thing to check is the display screen where you will hopefully see a code which tells an engineer what the problem is.

Common Solar Inverter Error Codes

Manufacturer: ABB / Fimer / Power One

E018 – Leak Fault – Leakage current fail
E021 – Internal Error
E025 – Riso Low –  Insulation fault on Solar Array
E031 – Error Read V – Wrong V Measure
W003 – Grid fault
W010 – Fan Fault

Manufacturer: SMA

64xx  – Interference device
3501 – Insulation resistance
1302 – Grid fault

Manufacturer: Fronius

401 – Communication issue with power stage set
475, 502 – Insulation resistance
509 – No energy fed in the past 24 hours

Addressing Issues Quickly

The benefit of understanding the nature of the fault is that it can cut down the time that the system spends offline. Rather than having to book an engineer to come and diagnose the fault, if we are made aware of what is wrong, and we know the inverter cannot be fixed, we can either make an immediate warranty claim or order a replacement inverter for immediate installation.
From a financial perspective, being aware of your systems status is of paramount importance. Put simply: if the system is off it is not making or saving you money. 
Subject to when your array was installed, a 30kW inverter, off for 2 weeks in the summer, will mean you miss out on c. £800 of revenue/electricity savings.
With this in mind, if you are unable to check the system status regularly, it makes sense to install remote monitoring hardware and software. These systems send the realtime performance and status data to an online portal that can be viewed from anywhere in the world. Additionally, they can be set up to alert you to system failures or under production.

If you do not have time to monitor the performance of your array yourself, why not place your system in one of BeBa’s maintenance portfolios? We are trusted by over 500 clients to proactively monitor their systems and react to any issues that present themselves. Moreover, if we cannot diagnose the fault remotely, our packages include free call outs so that you only need to pay for parts/labour not included in your maintenance agreement.