Siemens SINAMICS CU240S DP-F Operating Instructions Manual page 127

Parameter value (PWE) 3
In case of PROFIBUS or PROFINET communication the parameter value (PWE) is always
transmitted as a double word (32-bit). Only one parameter value at a time can be transferred
in a telegram.
A 32-bit parameter value comprises PWE1 (high-order word, 3rd word) and PWE2 (low-
order word, 4th word).
A 16-bit parameter value is transferred in PWE2 (low-order word, 4th word). PWE1 (high-
order word, 3rd word) must be set to 0 on the PROFIBUS-DP master / PROFInet I/O
controller in this case.
Note
In case of communication via USS, you can configure the word length in P2013. For details,
refer the section "Communication via USS".
Rules for processing requests/responses
● A request or a response can only ever refer to one parameter.
● The master must repeat a request continuously until it has received the appropriate
● The master detects the response to a request it has sent by
● The complete request must be sent in one telegram. Request telegrams cannot be split.
● In the case of response telegrams which contain parameter values, the drive always
Control Units CU240S
Operating Instructions, 07/2008 - FW 3.2, A5E00766042B AD
and 4 word
rd th
response.
– evaluating the response identifier,
– evaluating the parameter number PNU,
– evaluating the parameter index IND if necessary, or
– evaluating the parameter value PWE if necessary.
The same applies to responses.
returns the current parameter value when repeating response telegrams.
Communication
6.1 PROFIdrive Profile V4.1
127