Rooftop solar DC isolator catches fire on a home in New Lambton, Newcastle

What happened

In early October 2020 Fire and Rescue NSW crews attended a home in New Lambton, Newcastle, New South Wales, Australia, after a fire on the roof. They found that the rooftop solar PV isolation switch (the DC isolator mounted next to the panel array) had caught fire. Firefighters put the fire out quickly and stopped it spreading into the roof. No injuries were reported. The report noted that the isolator had some weather protection from a shroud.

The cause of the failure was not reported. The article set the incident against earlier Fire and Rescue NSW statements that solar system fires in the state had risen over five years and that DC isolator switches accounted for around half of PV fire incidents in the state. Rooftop DC isolators are required in Australia under the AS/NZS 5033 standard.

Contributing factors

The fire started in the rooftop DC isolator switch. The specific cause of the failure was not reported. The isolator had a weather shroud fitted.

Lessons learned

1. Treat rooftop DC isolators as a known fire initiation point and include them in every periodic inspection and system test.
2. Check isolator enclosures for water ingress, ultraviolet degradation and loose terminations, even where a weather shroud is fitted.
3. Make sure occupants know how to recognise smoke or scorching around roof-mounted switchgear and to call the fire service rather than attempt to operate the switch.

Source

solarquotes.com.au