The central devices can be configured in two different ways:
When the subunits have to be completely separated from each other for availability reasons, it is appropriate to use two standard racks (UR1 and UR2). Each rack accommodates one CPU and one power supply (PS). If extremely high availability is required, two redundant power supply modules can be used. The distance between the two racks can be up to 10 km.
Two CPUs, each with either a single or a redundant power supply, are plugged into the UR2-H rack with a segmented backplane bus. This enables an extremely compact configuration.