Siemens Sentron 7KN POWERCENTER 1000 Manual page 64

Functions
6.4 Modbus TCP connection
In the powerconfig PC version, the device addresses can be set in the communication view.
If the Unit ID information is not available, a device can be identified by querying the
identification parameters (order number, serial number and plant identification number) if all
24 possible unit IDs are checked.
The device addresses of the communication-capable circuit protection devices incl. the
7KN Powercenter 1000 are transmitted to the "Unit_ID" (Unit Identifier) field of the Modbus
protocol.
For the information of the 7KN Powercenter 1000 itself, such as its operating hours or the
system time, this means that 0xFF must be entered in the Unit ID. The first device is
addressed with 0x01. If e.g. a 3NA COM fuse has been added at the first position, a valid
voltage measurement value cannot be read out here, because this is only supported by
5SL6 COM and 5SV6 COM.
62
Circuit protection devices with communication and metering function
System Manual, 06/2021, L1V30827018B-01