The whole power infrastructure of the data center is designed for multiple redundancy. Two electrical supply-lines ensure the power supply for the network-infrastructure. The feed happens direct at the network level 5 with 10 kV. Each ring has a different transformer station, which are geographic separated. The connection is made via the 5th and 6th district of Vienna. There are two separate 10 kV transformers in the house. If one of the two power supplies is not working properly (voltage drop, the asynchrony of phases), this will be spun off immediately. For safety reasons, the diesel engine is already hoocked up from this point. Diesel supply agreements ensure a smooth supply around the clock.
Diesel supplies are available for at least 72 hours. Separate UPS systems guarantee the power supply for the whole infrastructure of the data center. If a server is equipped with redundant power supplies it is once connected to UPS system A and once to UPS system B. Even, when a UPS system would fail entirely, the power supply would be placed through the other UPS system. If a UPS requires service, the other UPS can take over all activities (bypass circuit). So failure-free maintenance is covered. The bridging time of the UPS is 2-3 hours. If the power fails on the network side and the UPS becomes active, the preheated diesel will go productive immediately.