Beckhoff EL1918 - System description; The Beckhoff EtherCAT Terminal system

System description
EL1918 and EL1918-220016 Version: 2.0.0
3 System description
3.1 The Beckhoff EtherCAT Terminal system
The Beckhoff EtherCAT Terminal system is used for decentralized connection of sensors and actuators to a
controller. The components of the Beckhoff EtherCAT Terminal system are mainly used in industrial
automation and building management systems. As a minimum, a bus station consists of an EtherCAT
Coupler and connected EtherCAT Terminals. The EtherCAT Coupler forms the communication interface to
the higher-level controller, while the EtherCAT Terminals form the interface to the sensors and actuators.
The whole bus station is clipped onto a 35mm DIN mounting rail (EN 60715). The mechanical link of the bus
station is established with a slot and key system on EtherCAT Couplers and EtherCAT Terminals.
The sensors and actuators are connected with the terminals via the screwless (spring-loaded) connection
system.
Fig.1: Slot and key system and screwless (spring-loaded) connection system