Fire at the DC terminal of the photovoltaic inverter

Can a PV system cause a DC arc flash?

During the course of fire on a building with a PV system, DC cable insulation can melt and cause a DC arc flash. The same may occur if a PV system is disconnected incorrectly. DC arcs are not only an additional life safety threat to firefighters, but also an ignition source, which will be discussed later in more detail.

Are solar PV systems causing fires?

Our engineers and inspectors have inspected over 10,000 grid-connected solar PV systems in the past ten years. During this time, we have concluded that there are three main causes of fires: DC isolators, especially the DC isolators located at the roof (rooftop isolators), are a known common cause of fires in PV systems.

What does a PV inverter do?

The inverter is a complex part of a PV system that actively manages and converts the direct current (DC) from the PV modules into alternating current (AC). Most of the PV-related fire incidents are not initiated by inverter failures.

Can a fire department disconnect a PV system?

Disconnecting PV systems should normally not be left to the fire department. 23. PV systems should only be installed and commissioned by qualified contractors. Training courses and certification processes are available. 24.

What happens if a PV system starts a fire?

For the fires initiated by a PV system, the fault tree is separated into six major events, which are ignitions caused by an electric malfunction in the PV module, isolator, inverter, combiner box or fuse, cable, and connector.

Are DC isolators a fire hazard?

DC isolators, especially the DC isolators located at the roof (rooftop isolators), are a known common cause of fires in PV systems. Historically, rooftop isolators have been a requirement in Australia to allow fire safety services and other workers to disconnect the system at the array – i.e. while on the roof.