Communication
6.4 Communication via PROFIBUS
Control Units CU240S
162
Operating Instructions, 07/2008 - FW 3.2, A5E00766042B AD
Information about the parameter request:
● Request_reference:
The value is selected at random from the valid value range. The request reference
establishes the relationship between request and response.
● Request_ID:
0x02 --> This identifier is required for a write request.
● Drive_object_ID:
0x00 -> Device-Representative (for G120 inverters = 0).
● No_of_parameters:
0x01 --> One parameter request.
● Attribute:
0x10 -> The parameter value are to be written.
● No_of_elements:
0x01 -> 1 array element is written.
● Parameter_number:
043A -> Parameter P1082 (max. frequency); 043A hex = 1082 dec.
● Subindex:
0x00 -> ID for the first array element.
● Format:
0x43 -> Floating Point data type (refer to the Parameter List).
● No_of_values:
0x01 -> One value is written to the parameter in the specified format.
● Value:
1.002 -> maximum frequency 100 Hz.
For the acyclic communication in OB1 a write request must be send to the drive with
WR_REC (SFC 58)
Figure 6-13 Acyclic communication in OB1
