Photovoltaic installations must follow specific safety rules. Currently, the IEC 60364-712 standard requires protection from three main hazards.
Protecting people from electric shock
To keep users safe from electric shocks, the standard requires double or reinforced insulation. This means that if there is an electrical fault on a piece of equipment, the exposed parts (the parts people could potentially come into contact with) are safe, since they are protected by two layers of insulation.
Preventing fires caused by isolation faults
In the – albeit rare – event of an isolation fault, the standard requires measures to prevent a fire from starting. Isolation must be monitored at all times by an isolation fault detection system, which picks up faults between active components and earth.
An overcurrent can occur between the two active phases of the installation. Whereas circuit breakers are not the most appropriate solution for protecting people, here they are effective – and required – to cut off power to the installation in the event of an overcurrent (current that is higher than what the wiring is designed to withstand).