Siemens SINAMICS G120 - SDO Services

Configuring the fieldbus
7.7 Communication over CANopen
Inverter with CU230P-2 Control Units
192 Operating Instructions, 11/2013, FW V4.6.6, A5E02430659B AG
The NMT master can simultaneously direct a request to one or more slaves. The following is
applicable:
● Requirement of a slave:
The controller accesses the slave with its node ID (1 - 127).
● Requirement for all slaves:
Node ID = 0
The current state of the node is displayed via p8685. It can also be changed directly using
this parameter:
•
p8685 = 0
Initializing (display only)
•
p8685 = 4
Stopped
•
p8685 = 5
Operational
•
p8685 = 127
Pre
-Operational (factory setting)
•
p8685 = 128
Reset Node
•
p8685 = 129
Reset
Communication
You can also change the NMT state in STARTER via "Control_Unit / Communication / CAN"
under the "Network-Management" tab.
7.7.1.2
SDO services
You can access the object directory of the connected drive unit using the SDO services.
An SDO connection is a peer-to-peer coupling between an SDO client and a server.
The drive unit with its object directory is an SDO server.
The identifiers for the SDO channel of a drive unit are defined according to CANopen as
follows.
Receiving:
Server ⇐ client:
COB ID = 600 hex + node ID
Transmitting:
Server ⇒ client:
COB ID = 580 hex + node ID
Properties
The SDOs have the following properties:
● An SDO connection exists only in the Pre-Operational and Operational states
● Transmission is confirmed
● Asynchronous transmission (matches the acyclical communication via PROFIBUS DB)
● Transmission of values > 4 bytes (normal transfer)
● Transmission of values ≤ 4 bytes (expedited transfer)
● All drive unit parameters can be addressed via SDO