A central data collection apparatus (1, 1', 1"), wherein the central data collection apparatus comprises: an interface for receiving data relating to devices (6, 7, 8, 12, 12', 12") and which data is provided by control devices arranged at a plurality of different installation sites (4, 5) for monitoring the operation of the respective devices (6, 7, 8, 12, 12', 12") at the respective installation sites, a data storage for storing the data received via the interface, a user credential storage for storing credentials of authorized users allowed to access data relating to the devices (6, 7, 8, 12, 12', 12"), and a data distributor configured to receive a request for data regarding a specific device (6, 7, 8, 12, 12', 12") identified in a request from a user equipment (16, 16"), to access the user credential storage for determining the access rights of the user in question, to determine what parts of the data regarding the identified device (6, 7, 8, 12, 12', 12") the user is authorized to receive, and to allow the user equipment (16, 16") to access the part of the data the user is authorized to access, characterized in that: the central data collection apparatus (1, 1', 1") maintains for each device whose data is stored in the data storage a unique identifier which is also available for the user equipment (16, 16') at the installation site of the device in question (12, 12' 12"), and the central data collection apparatus (1, 1', 1") is configured to retrieve from the received request a unique identifier and if this identifier corresponds to an identifier maintained at the central data collection apparatus for a device (12, 12' 12"), identify this device (12, 12' 12") as the device to which the request relates. an interface for receiving data relating to devices (6, 7, 8, 12, 12', 12") and which data is provided by control devices arranged at a plurality of different installation sites (4, 5) for monitoring the operation of the respective devices (6, 7, 8, 12, 12', 12") at the respective installation sites, a data storage for storing the data received via the interface, a user credential storage for storing credentials of authorized users allowed to access data relating to the devices (6, 7, 8, 12, 12', 12"), and a data distributor configured to receive a request for data regarding a specific device (6, 7, 8, 12, 12', 12") identified in a request from a user equipment (16, 16"), to access the user credential storage for determining the access rights of the user in question, to determine what parts of the data regarding the identified device (6, 7, 8, 12, 12', 12") the user is authorized to receive, and to allow the user equipment (16, 16") to access the part of the data the user is authorized to access, characterized in that: the central data collection apparatus (1, 1', 1") maintains for each device whose data is stored in the data storage a unique identifier which is also available for the user equipment (16, 16') at the installation site of the device in question (12, 12' 12"), and the central data collection apparatus (1, 1', 1") is configured to retrieve from the received request a unique identifier and if this identifier corresponds to an identifier maintained at the central data collection apparatus for a device (12, 12' 12"), identify this device (12, 12' 12") as the device to which the request relates. the central data collection apparatus (1, 1', 1") maintains for each device whose data is stored in the data storage a unique identifier which is also available for the user equipment (16, 16') at the installation site of the device in question (12, 12' 12"), and the central data collection apparatus (1, 1', 1") is configured to retrieve from the received request a unique identifier and if this identifier corresponds to an identifier maintained at the central data collection apparatus for a device (12, 12' 12"), identify this device (12, 12' 12") as the device to which the request relates.