INVERTER 3 NOT OPERATING
The major concern is that inverter number 3 (SMA 15kW model) is not working. The display reads “INSTALLATION FAILURE”, indicating that the connection to the AC side is not correctly set up.
On further investigation it became clear that the AC isolator switch did not appear to be working properly.
AC ISOLATOR SWITCH
The AC isolator appears to have had a loose connection, which has lead to overheating over time. This issue has reached the point where the connections have burnt out, meaning that the switch was not “on” and the inverter has been unable to deliver electricity to the AC connection.
This switch will need to be replaced, and we recommend checking all other terminations in the system to ensure they are connected correctly.
METER CABINET – WATER INGRESS
Over time the waterproof seals on the meter cabinet have degraded to the point where water is able to enter and collect. This can cause various issues, including the potential for the system to partially of wholly shut down if protective devices trip.
The seals around the edge of the cabinet have all been built up with dirt which appears to be absorbing water and allowing it to enter at the cabinet edges. These will need to be cleared out and the seals made watertight.
The earth connection at the bottom of the cabinet is of particular concern, since the water has already started to corrode the connection.
This issue will need to be addressed.
The monitoring system did not appear to be functioning, or indeed to have a working power supply. We recommend investigating this further, since we would have expected this system to alert the owner to the inverter issue outlined above.
DIRT ON PANEL SURFACE
There is a substantial amount of dirt on the surface of the panels and the generation could certainly be improved by cleaning them.
GENERAL CLEANLINESS AND AIR FLOW
The inverter enclosure has accumulated a lot of dirt, cobwebs and insect remains. Whilst these are not all necessarily causing direct losses, they will affect the airflow around the inverter units and may shorten their operating lifespan.
We would recommend creating vents at the sides of the cabinet and thoroughly cleaning out the current dirt and cobwebs.