Operating Instructions

Communication over CANopen
Fieldbuses
170 Function Manual, 04/2018, FW V4.7 SP10, A5E34229197B AE
Grounding the CANopen Control Unit
The CAN ground (pin 3) and the optional ground are electrically isolated from the ground
potential of the system.
The optional shield (pin 5) and the connector housing are connected with the ground
potential of the system.
CANopen functions of the inverter
CANopen is a communication protocol with line-type topology that operates on the basis of
communication objects (COB).
SINAMICS G120 inverters with CANopen interface comply with the following standards:
● CiA 301 (Application Layer and Communication Profile)
● CiA 303-3 (Indicator Specification)
● CiA 306 (Electronic Data Sheet Specification for CANopen)
● CiA 402 (Device Profile for Drives and Motion Control)
Communication objects (COB)
The inverter operates with the following communication objects:
●
NMT
Network management (NMT service) (Page 172)
Network management objects for controlling CANopen communication and for monitoring
the individual nodes on the basis of a master-slave relationship.
●
SDO
SDO services (Page 175)
Service data objects for reading and changing parameters
●
PDO
PDO services (Page 179)
Process data objects to transfer process data, TPDO to transmit, RPDO to receive
process data
●
SYNC
Synchronization objects
●
EMCY
Time stamp and fault messages
COB ID
A communication object contains the data to be transferred and a unique 11-bit COB ID. The
COB ID also defines the priority for processing the communication objects. The
communication object with the lowest COB ID always has the highest priority.