The Fronius Rapid Shutdown Box – Duo is the Fronius solution to NEC Rapid Shutdown Code Requirements. The Duo model is used for up to two strings of modules.

NEC 2014 code (690.12) provides safety considerations for firefighters responding to a fire at a PV enabled home. The goal is to safely and quickly de-energize the system so that firefighters can safely address the emergency. In the case of the Fronius unit, responders would disable power to the property, which would disable the Fronius inverter, which would in turn trigger the Rapid Shutdown Box to disconnect power from the array. The Box is installed outdoors within 10′ of the array, meaning any high voltage DC transmission wires between the array and the inverter are brought to a minimum safe voltage within seconds of the shutdown being triggered.

Signal wires can be run in same DC homerun conduit. A maximum of five units can be used together in one system.

Compatible inverters: Fronius Galvo, Fronius Primo, Fronius Symo (excluding Fronius Symo 15.0-3 208).

Max. signal wire size: 14 ga
Max. DC homerun wire size: 10 ga
NEMA4X outdoor rated enclosure

Max. number of strings: one
Max. output current: 17 A
Max. input current: 17A
Max. voltage: 600 V
Power supply: DC power from array (max. 3 watts)
Dimensions: 7.9 x 5.5″ x 3.5″
Weighs: 4.4 lbs