EC 121
S-DIAS ETHERCAT CONTROL MODULE
Page 30
02.07.2020
9.3
Operating Mode
The EC 121 can be operated in either in
DC-Synchronous
or
FreeRun
mode. In FreeRun
mode, the EC 121 is not synchronized with EtherCAT. In this case. the module operates
with a preset cycle time of 4 ms by default. This cycle time can be set via the object
0xFB10. Further information can be found in section 10.4.20.
In DC-Synchronous mode, the EC 121 uses the distributed clock as a reference and oper-
ates with the specified cycle time. Possible cycle times are 250 µs, 500 µs and between 1
ms and 32 ms in millisecond intervals. Whether operation is possible with the cycle time
setting depends on the cycle times supported by the connected S-DIAS Slaves. This infor-
mation can be found in the product documentation of the corresponding S-DIAS slave.
Otherwise the capacity of the system plays a role
– depending on the number and configu-
ration of S-DIAS slaves on the EC 121
– the possible cycle time for proper operation can
vary.
