Hi Timon,
The standard representation of a transportation Modbus Frame is 16 bits unsigned integer (0..65535 in decimal mode).
It can represent a float number in a fixed-point form.
Ie : 125.36 can appear in the frame as 12536 integer or any other integer representation .
It basically not support floating numbers (with the Gould Modicon 1970 definition).
www.modbus.org/docs/PI_MBUS_300.pdf
However, you must link a ChanAi object (in the node column) with a corresponding (32 bit float number) Ai object in the Plant column.
This object convert Raw value (Unsigned integer) in Actual value (32 float number)
An example with Modbus TCP/IP:
/BP