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FnIO EtherCAT Network Adaptor NA-9286
FnIO S-Series
Copyright(C) CREVIS Co.,Ltd Support +82-31-899-4599 URL : www.crevis.co.kr
Servo drive profile according to IEC 61800-7-204(SERCOS) (SoE)
SERCOS interface™ is acknowledged as a high-performance real-time communication interface, particularly
for motion control applications. The SERCOS profile for servo drives and the communication technology are
covered by the IEC 61800-7-204 standard. The mapping of this profile to EtherCAT (SoE) is specified in part
304 [2]. The service channel, and therefore access to all parameters and functions residing in the drive, is based
on the EtherCAT mailbox.
Here too, the focus is on compatibility with the existing protocol (access to value, attribute, name, units, etc.
of the IDNs) and expandability with regard to data length limitation. The process data, with SERCOS in the
form of AT and MDT data, are transferred using EtherCAT device protocol mechanisms. The mapping is
similar to the SERCOS mapping. The EtherCAT slave state machine can also be mapped easily to the phases of
the SERCOS protocol. EtherCAT provides advanced real-time Ethernet technology for this device profile,
which is particularly widespread in CNC applications. Optionally, the command position, speed or torque can be
transferred. Depending on the implementation, it is even possible to continue using the same configuration tools
for the drives.
Ethernet over EtherCAT (EoE)
The EtherCAT technology is not only fully Ethernet-compatible, but also characterized by particular openness
“by design”: the protocol tolerates other Ethernet-based services and protocols on the same physical network –
usually even with minimum loss of performance. There is no restriction on the type of Ethernet device that can
be connected within the EtherCAT segment via a switchport.
The Ethernet frames are tunneled via the EtherCAT protocol, which is the standard approach for internet
applications(e.g. VPN, PPPoE (DSL), etc.). The EtherCAT network is fully transparent for the Ethernet device,
and the real-time characteristics are not impaired (see Fig. 2).
The master acts like a layer 2 switch that redirects the frames to the respective devices according to the address
information. All internet technologies can therefore also be used in the EtherCAT environment: integrated web
server, e-mail, FTP transfer, etc.
<Fig. 2> Transparent for all Ethernet Protocols
