Fieldbus

AS-i (Actuator Sensor Interface) is the world’s only standardised Fieldbus system for the lower process level. Using just one port and only one cable with two buffered fibres, this simple connection system can network up to 31 sensors and actuators/AS-i modules with the controller level. In this context, the AS-i cable is responsible not only for exchanging data, but also for supplying power to the slaves. A cyclic transfer rate of ≤ 5 ms can be achieved here with a cable length of 100 m. As a result, this open industry standard (which is not tied to a specific manufacturer) enables fast, efficient cabling in industrial automation, which ultimately reduces costs.

The AS International Association e.V. promotes the expansion and standardisation of the AS-i protocol standard. LAPP is a member of this association and plays an active role in further developing the standard.

PROFIBUS (Process Field Bus) is a standard for Fieldbus communication, and one of the world’s current leading Fieldbuses. It enables data to be exchanged cyclically between devices on the lower field level (decentralised peripheral devices, slaves) and higher-level controller units (central masters). It has now become a key communication protocol used in manufacturing technology, as well as process technology and engineering. The master-slave system can use both twisted pair cables and fibre optic cables.
Higher speeds are achieved by the successor PROFINET with its Ethernet solution.
LAPP Kabel is a member of the user organisation PROFIBUS Nutzerorganisation e.V. (PNO) and plays an active role in further developing PROFIBUS.
The following two variants of PROFIBUS are primarily used.

PROFIBUS DP
Fieldbus communication in manufacturing technology can be handled using either a mono-master set-up or a multi-master system (where several masters are connected to a bus). The masters query input information from the slaves at cyclic intervals and return output information. The PROFIBUS

DP system is available in different versions:

• DP-V0 for cyclic communication,
• DP-V1 additionally for acyclic communication,
• DP-V2 additionally for isochronous real-time functionality, use of time stamps, and slave-to-slave communication.

PROFIBUS DP offers a transmission rate of 12 Mbit/s and can combine up to 126 devices (masters and slaves) in a network.

PROFIBUS PA
PROFIBUS PA is used for communication in process automation. As the power is limited, PROFIBUS PA is ideally suited for use in potentially explosive atmospheres. The transmission rate of 31.25 kbit/s allows for long cable paths and a high degree of resistance to electromagnetic interference.

The names of the PROFIBUS-compliant products from LAPP&apo;s UNITRONIC® range (cables) and EPIC Data range (connectors) include the designation "BUS DP" for PROFIBUS DP and "PA" for PROFIBUS PA.

The CANopen standard has taken the CAN (Controller Area Network) Fieldbus system that was originally developed for the automotive industry and has expanded it to include a communication profile. This makes CANopen an open protocol standard for use not only in automation technology, but also many other industries, such as medicine, railways, etc., predominantly in Europe.

In the serial CAN system, the data is exchanged in the form of telegrams on both a cyclic and event-driven basis, and the exchange is managed via the first two layers of the OSI model. The network participants with equal status independently transfer their messages to the bus at a secure data transmission rate of up to 1 Mbit/s, over a cable length of 40 m. In the process, data is exchanged in real time.

In the higher-level CANopen system, an application layer is integrated to provide a communication profile. By means of standardised interfaces, this profile is able to individually address the device and application profiles of the device classes used in the network. As a result, the communication profile controls which telegrams are used to exchange which device data.

CANopen is maintained by CiA (CAN in Automation).

In Asia, CC-Link is the leading open industry standard with pronounced deterministic characteristics, used for exchanging data between the control and manufacturing level. It is available in different variants. In the standard variant, CC-Link is a fieldbus system enabling a data transmission rate of up to 10 Mbit/s over a total cable length of 100 m, as well as real-time communication with up to 64 devices in the network. As the transmission distance can be extended to up to 1,200 m with lower network speed, CC-Link is also suitable for large-scale applications. The simple structure of this standard suffices for a wide range of automation technology tasks. This network technology is also increasingly being used in Europe, as CC-Link-compatible products from different manufacturers can be integrated very easily.

You can find more information about the Ethernet-based variant of CC-Link under CC-Link IE.

CC-Link is standardised by the CLPA (CC-Link Partner Association) user organisation.

LAPP is a member of the CLPA and is actively involved in further developing CC-Link.