Page 10 - Energize September 2022

NEWS

Why solar panels need to be inspected

ecent observations of urban-domestic and SME offices, Access to panels
sporting row upon row of solar panels, clearly shows evidence In order to walk and scan the panels, one needs access to the
Rof the increasing trend by these sectors to switch from panels. The Fluke 401 or TiS60 imagers suit this application
traditional sources of energy to alternative or clean energy – in this well, as long as the installations are spaced so that maintenance
instance, solar energy. technicians are able to walk along the series and scan the panels
Solar panels are made up of cells joined together in series and individually. Manually tested, the Ti’s pictures are saved with time
relayed to a control box. And, of course, when connected in series, and date, as well as tagged with voice memo recordings of where
the panel is only as good as the weakest cell. If one of these cells the panels are located. The photos can then be downloaded so that
fails, it affects the overall performance of the entire panel. The case the technician knows exactly where to find the particular problem
study illustrated here is of a roof-top installation situated on the Old panel. One can even take the serial number of the panel, as well as
Mutual Building, Johannesburg. 4 extra photos of the panel being worked on.
Walk access to solar panels is not always possible. This then
Installation calls for drone technology, to enable remote viewing. An example
Close attention should be paid to the installation of panels. If, as in of this would be the Northern Cape’s vast solar arrays.
the case illustrated in Image 1, the panels are located too close to
the concrete roof surface, they are affected by radiated heat. This is Panel Lifetime
evidenced by quite a few cells failing along the bottom of the panels. Be aware that solar panels do degrade their output performance
In this installation there is no more than 15cm clearance between over time, and they definitely have a finite lifecycle, thus regular
the roof and the bottom edge of the panels. For this installation to maintenance is absolutely necessary.
be successful and give better performance, the panels would have to
be raised, allowing for better ventilation and less heat build-up at the Other devices technicians use to test and troubleshoot solar
bottom. Fluke’s IRR1-Sol Solar irradiance meter not only measures installations:
panel performance and temperature, but it is specifically engineered • Fluke 393FC Clamp meter/troubleshooting tool measures load
to perfectly align solar panels for optimum performance. It accurately and voltage levels.
measures the irradiance – the angle of the panel vs angle of the sun. • Fluke 1775 PQ Logger measures power inverter efficiency,
power output and power quality of solar systems.
Panel Inspections • Fluke BT520 measures and tests the batteries in solar
Ideal conditions for inspecting solar panels are clear, sunny skies applications, and identifies the weakest battery in the string,
for optimum readings. Faulty cells would be a lot warmer because allowing owners to choose to replace only one particular
overcast conditions do not produce maximum performance. battery, if needed.
This image clearly illustrates the advantages of a thermal imager.
Looking at the panels with the naked eye, one would not pick up Contact Comtest, Phone 010 595-1821, sales@comtest.co.za,
any anomalies. But, with a good imager, one can very clearly see the www.comtest.co.za
problems with this panel. One block is heating up relative to the rest Facebook: bit.ly/3iuk4cg
of the cells. This indicates a faulty panel, and that one of the cells YouTube: bit.ly/2V4nc6j
that are connected in series has failed, dropping the performance of LinkedIn: bit.ly/3rpTu86
the panel. This panel needs to be replaced. HashTags: #Solarsolutions #Fluke #Comtest #Solar

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