In general, a firefighter’s switch should be as close as possible to the PV generator. Usually they are installed at the entry of the building to keep the DC lines inside the building disconnected in case of an emergency. Most of the switches can be mounted outside, although it is recommended to place them underneath a roof. Operation temperatures of the switch should be considered and accessibility kept in mind for switches that need to be manually reset. The power supply of the control circuit should be connected shortly after the AC output of the inverter to ensure a release
of the firefighter’s switch as soon as the AC power at the inverter is off.