With the One Cable Automation philosophy, Beckhoff enables entirely new concepts in machine and systems engineering. The concept is based on the ability to connect automation components, decentralised terminal boxes and even entire machine modules with a single EtherCAT P cable, which carries the EtherCAT communication as well as the power supply for the system and peripherals. One Cable Automation not only reduces material costs, the time and effort spent on system installation and the risk of errors, it also enables a much more flexible design, including the possibility of a machine without control cabinets.

 

The underlying idea of One Cable Automation (OCA) at the field level is to significantly reduce the number of parts and subsequently simplify inventory management and installation requirements for machine builders and operators alike. EtherCAT P is a technological milestone that integrates EtherCAT and power supply in a standard 4-wire Ethernet cable. Beckhoff has developed a special M8 connector for EtherCAT P with a mechanical coding that prevents mis-mating with connectors for standard EtherCAT slaves.

 

The 24 V DC supply of the EtherCAT P slaves, and connected sensors and actuators is integrated into the cable. US (system and sensor supply) and UP (peripherals voltage for actuators) are galvanically isolated, each supplying up to 3 A of current. All the benefits of EtherCAT can be retained, such as the free choice of topologies through cascadability, high speed communication, optimised bandwidth utilisation, continuous message processing, highly accurate synchronisation and extensive diagnostic capabilities, among others. With EtherCAT P, the US and UP currents are injected directly into the wires of the 100 Mbit/s cable for a highly cost-effective and compact connection.

 

EtherCAT P: From 24 V sensor to 600 V drive

EtherCAT P delivers benefits for connecting small distributed I/O stations in terminal boxes as well as for local I/O components within the process. In order to connect components with higher voltage and/or current requirements, a complete EtherCAT P connector family has been developed that covers all applications up to drives with power ratings of up to 400 V AC or 600 V DC and currents up to 64 A.

 

To transmit more power, a compact EtherCAT P element featuring the same pin assignments as the M8 connector has been combined with additional supply lines, resulting in the B12, B17, B23 and B36 EtherCAT P connectors for various performance classes. Equipped with a twist-lock connection system and featuring protection class IP 67, they provide quick and reliable connectivity directly on the machine while delivering optimised scalability for numerous applications, such as: B12 for connecting stepper motors with controllers rated at up to 48 V DC and 10 A; B17 for asynchronous motors with frequency converters rated at up to 230 V DC and 14A; B23 for complete switching cabinets rated at up to 400 V AC and 30 A; and B36 for connecting robots rated at up to 400 V AC and 64 A

 

One Cable Automation as an innovation driver in machine design

With its simpler and more flexible system cabling, OCA considerably reduces the complexity of machine design and with it, development and production costs. This is because automation components, distributed terminal boxes and even individual machine modules and robots receive power supply, and control signals over a single branched cable. As a result, large control cabinets frequently used in large installations are no longer needed. Modular machine and system concepts can now be implemented with lower assembly and startup costs, reduced footprints and maximised flexibility.

 

Eliminating separate power lines reduces the cost of materials and assembly, as well as the occurrence of installation errors while minimising the space requirements in drag chains, control cabinets and the machine itself. Other benefits include smaller and more clearly arranged cable runs, as well as smaller sensors and actuators. All of these features deliver a new degree of flexibility in machine design.

 

To simplify machine design even more, a special TwinCAT utility programme is available for specifying individual power users and cable lengths, as well as deploying the most efficient EtherCAT P network. Since the system knows every user’s specifications, it can also take into account the individual devices’ power consumption over time. For example, if two actuators never switch at the same time, they will never require full power input at the same time. This produces additional savings potential with regard to power supplies and power supply units.

 

OCA makes plug-and-play automation possible

In the future, plug-and-play automation will deliver maximum efficiency. As EtherCAT P connectors for various power requirements become established as a standard, the idea of industrial connector strips – for 24 V and for higher power classes – is not far-fetched.

 

Machine designers could distribute such ‘connector strips’ with great flexibility and at low cost in the machine or installation, according to the individual application requirements. Such a plug-and-work design, which requires only the insertion of a matching EtherCAT P cable, would make it easy to connect the necessary sensors and actuators as well as the distribution boxes and standalone machine modules.