Siemens SINAMICS G120 Operating Instructions Manual page 113

Description
Telegrams with both a variable and fixed length can be used. This can be selected using
parameters p2022 and p2023 to define the length of the PZD and the PKW within the net
data.
STX
LGE
ADR
Net data
(example)
BCC
Start delay
The start delay must be maintained before a new master telegram is started.
STX
The STX block is an ASCII character (0x02) and indicates the beginning of a message.
LGE
LGE specifies the number of bytes that following in the telegram. It is defined as the sum of
the following bytes
● Net data
● ADR
● BCC
The actual overall telegram length is two bytes longer because STX and LGE are not
counted in LGE.
SINAMICS G120C Inverter
Operating Instructions, 01/2011, FW 4.4, A5E02999804A AB
1 byte
1 byte
1 byte
PKW 8 bytes (4 words: PKE + IND + PWE1 + PWE2)
PZD 4 bytes (2 words: PZD1 + PZD2)
1 byte
Configuring the fieldbus
7.3 Communication via RS485
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