Advantages

sercos III is the logical next step in the evolutionary development of the sercos technology. Besides its low costs and excellent performance, sercos III also specifies numerous new functions that are trend-setting in automation technology.
 

What is new?

• Standard Ethernet is used as the physical layer and protocol
• Faster due to higher bandwidth and shorter cycle times
• More synchronous due to a highlyprecise synchronization procedure with run-time compensation
• More universal due to a new communication mechanism, as well as new and expanded device profiles
• New, innovative communication functions, e.g. direct cross communication and integrated standard Ethernet communication
• Fast medium redundancy in communication, resulting in improved machine availability
• Simple implementation

The advantages

Versatile

• All automation devices, such as controllers, servo drives and I/O periphery, communicate via a uniform Ethernet-based network for automation technology.
• Safe and non-safe participants can coexist in one network without influencing the security technology.
• All Ethernet-based protocols can be transmitted at the same time as real-time data without influencing the real-time characteristics.

Fast and direct

• High speed: sercos III uses the speed of Fast Ethernet (100 Mbit/s).
• Short runtimes: The runtimes through the network are reduced to a minimum. This is achieved by:
  • Extremely fast processing of the sercos III real-time messages when passing through the devices (“on-the-fly”)
  • No additional network components, e.g. hubs or switches
• Direct cross communication: all nodes can exchange data directly – with minimal idle time within one communication cycle.

Efficient

• Efficient usage of bandwidth: ideal utilization of bandwidth possible by means of multiplexing techniques.
• Arbitrary cycle time: The communication cycle can be varied between 31.25 μs and 65 ms.

Synchronous

• Synchronicity down to a fraction of a microsecond

Integrated

• All office communication protocols (e.g. TCP/IP, UDP/IP) can be transmitted parallel to sercos III real-time communication via the same cable. Synchronization and redundancy are not mutually exclusive.
• Standard Ethernet protocols use the MAC or IP addresses to communicate with individual sercos III devices. Tunneling of these protocols is not necessary.
• Commissioning and diagnosis of sercos III devices via standardized interfaces (SCI, S/IP, and FDT/DTM).

Safe

• Safety functions up to SIL3 according to IEC 61508 can be implemented with CIP Safety on sercos.
• The routing capability of CIP Safety supports safe device communication across network boundaries.
• A safety network can stretch across diverse CIP Safety networks, including, for example, Ethernet/IP, DeviceNet and sercos III.

High availability

• For high-availability automation solutions, sercos III automatically offers fail-safe communication in the case of a cable break or node failure through the use of a ring topology (ring redundancy).
• The time needed to detect and respond to a cable break is a maximum of 25 μs, so at most only the data from one cycle is lost and communication is continued afterwards.
• If a redundancy situation occurs, the synchronization quality is maintained.

Flexible

• Centralized and decentralized control architectures are supported.
• User-defined device configuration within the network.
• Support of ring or line topologies. In addition, hierarchical, synchronized and real-time coupled network structures can be implemented.
• Hot-plugging is supported without interference with real-time or synchronization functions.

Easy

• sercos III devices can be easily configured and commissioned by means of a uniform, integrated device model and universal, standardized device profiles.
• The protocol automatically detects the device and where it is connected in the topology. This makes it easy to localize the affected device for servicing.
• Easy wiring, as the physical order of the devices is not relevant and the order of connection of the two sercos III ports is not important.

Cost-effective

• Use of standard components allows for cost-effective implementation of hardware. Additional active network devices, e.g. switches or hubs, are not required.
• Master connectivity can be implemented in the hardware, hardware and software, or just the software.
• Slave connectivity is based on costefficient and flexible FPGA devices or integrated multi-protocol chips.

Standardized

• sercos has been an approved international standard for real-time communication since 1995 (IEC 61491).
• The real-time Ethernet protocol sercos III is part of IEC 61158 and IEC 61784. The device profile for drive communication is included in IEC 61800-7.
• Experts from the sercos working groups contribute to national and international standardization committees.

Non-proprietary

• sercos is a non-proprietary technology.
• The specifications are disclosed completely.
• sercos technology is owned by the sercos international e. V. user organization.
• Membership in the user organization is not required in order to use the sercos technology.

Future-proof

• sercos is an open, international standard.
• The specifications are maintained and further developed by experts in non-proprietary working groups.
• Good investment protection is provided by backwards compatibility.
• The technology is continuously developed and adapted to new market requirements.

Proven

• Products from leading automation manufacturers support sercos.
• sercos is widely accepted in many different industries, particularly with regard to demanding applications.
• Over 3 million sercos real-time nodes are used worldwide in more than 350,000 applications (and growing).