Operating instructions
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4.10.2 Communication via field bus connection (SDO1) 
If a frequency inverter has been defined as the system bus master and equipped with
a field bus interface, access to the parameterization of all the nodes in existence on 
the system bus is possible by means of this field bus interface via the first SDO chan-
nel (SDO1). An extension has been created in the protocol frame of the field buses fo
r
this purpose. 
Attention! The prerequisite for this mechanism is that the identifier setting for the
first SDO channel (SDO1) corresponds to the Predefined Connection Set. 
The parameter addressed must also exist in the system bus master. 
4.10.2.1 Profibus-DP 
If an object with communication channel (PKW) is used in Profibus-DP, access to all 
the other nodes on the system bus can be done via it. The structure of the communi-
cation channel permits an additional addressin
g of a system bus node. This is done by
the use of an unused byte in the communication channel. 
Communication channel PKW
  0 1  2 3 4 5 6 7
PKE  Index -  Data 
 AK/SPM Parameter
number
Data set  Node-ID 
system bus
Byte 3 is used to transmit the Node ID of the required node on the system bus. If byte 
3 = 0, the master inverter of the system bus is addressed. The display is binary
(0...63). 
4.10.2.2 RS232/RS485 with VECTRON bus protocol 
In the VECTRON bus protocol, there is a byte in the telegram header that is always
transmitted with 0 as a standard feature. 
ENQUIRY
0  1  2 3 4 5 6 
  Address  0  p  n  n  n ENQ  
Node-ID
system bus
Data set Parameter number     
SELECT
0  1  2  3 4       
 Address STX  0  p  n  n  n ... 
   Node-ID
system bus
Data set Parameter number   
Byte 1 in the enquiry and byte 2 in the select telegram are not defined and are used to
transmit the Node ID of the required node on the system bus. If this byte = 0, the 
master inverter of the system bus is addressed. The display is ASCII correspondin
g to 
the conventions for the display of the address in the VECTRON bus protocol. 
Note: If there is an NAK fault message, the error is to be read out from the
system bus master with node ID = 0 via parameter 11! 










