A multi-drop data network operating as a high speed backbone for Ethernet and CAN bus-based field devices offers cost and space savings thanks to just one data cable, multi-protocol transmission and a multi-drop connection. With the ABN300 series, KLG Smartec presents an Ethernet AUTBUS signal converter based on the AUTBUS industrial data bus standardised by the IEC.

AUTBUS data connection

The ABN300 series supports an AUTBUS data connection and, depending on the model variant, an additional interface for data transmission from devices with Ethernet, CAN or RS485 data connections. The ABN300 series enables the effective transmission of data protocols based on these interfaces via the AUTBUS data backbone network.

With a size of only 30x115x68mm and a weight of 200gr., the ABN300 signal converter series is suitable for integration into a wide variety of housing types and control cabinets thanks to its slim housing and integrated top-hat rail mounting clamp or with the optional screw fastening. The ABN300 series requires a supply voltage of 24-48 VDC, has a power consumption of only up to 3 watts and is designed for ambient temperatures of -40 to +70°C.

AUTBUS is an industrial broadband fieldbus that was standardised by the IEC in 2023. AUTBUS supports data transmission via a balanced cable, e.g. a simple twisted pair cable, or via an unbalanced cable, e.g. a coaxial cable. With a qualified twisted and shielded two-wire cable of type AWG-16 to AWG-26, up to 254 multidrop data network nodes can be reached over a distance of up to 500 metres at a data transmission speed of 100 Mbps. Compatibility with the data cables and connectors originally specified for Single Pair Ethernet (SPE) means that a stable data network can be installed, but it is also possible to use simple PCB connectors.

On a physical level, AUTBUS utilises OFDM (Orthogonal Frequency Division Multiplexing) technology to adapt to channel conditions and protect against narrowband interference, making AUTBUS a perfect solution for industrial communication technology in harsh environments. OFDM technology is used in wired and wireless communication. With its characteristics such as broadband, low latency and determinism, AUTBUS is predestined for the field of industrial wired data communication. The critical deterministic challenges exist in a variety of industrial applications for which AUTBUS can be of great benefit.

Technology advantages

A major advantage of AUTBUS is data transmission via a virtually uninterrupted data backbone network using a daisy-chain device connection. The twisted two-wire cable can, for example, be tapped directly and without cable interruption via a special SPE-T connector with a maximum stub length of upto 50 cm or the data cable can be disconnected and connected to a PCB connector with four 2-way bridged connections supplied directly with the ABN300. If the SPE connector or the PCB connector is disconnected from the ABN300, the AUTBUS backbone network is not interrupted as the cable is still bridged.

Increased reliability is achieved by connecting the two ends of the data cable together, taking into account the maximum cable length of up to 500 metres. This creates a data network ring without the need for an active ring redundancy manager. This makes it possible to connect end devices with an Ethernet connection or several such end devices to the AUTBUS backbone network via an unmanaged Ethernet switch.

AUTBUS also supports multi-protocol transmission through data tunnelling, i.e. Ethernet-based transmission protocols, for example, but also CAN bus or RS485 can be transmitted transparently from one data connection point to another simultaneously via the passive AUTBUS Multidrop Backbone without these protocols having to be translated or additionally configured.

Thanks to the standard AUTBUS Plug & Play (AP&P), the devices are very easy to install and configure. Depending on the end device, the operating mode is selected via a rotary switch integrated on the front and a DIP switch. A software configuration tool is also available for special applications.

Any ABN300 converter can be defined as the master for the entire AUTBUS communication; all other ABN300 converters are configured as clients. It is also possible, for example, to define the assignment of the data bandwidth if necessary, e.g. if devices with different transmission rates are to be integrated, such as the networking of e-charging stations and additional surveillance cameras or a WiFi router in an e-charging park

The main features of AUTBUS and the ABN 300 are:

• Up to 254 multidrop nodes
• 2-wire twisted pair cable (polarity insensitive)
• 100Mbps high data bandwidth
• Up to 500 metres distance
• Deterministic in real time
• Bus and ring topology
• Multi-bus protocol tunnelling: Ethernet based protocols, CAN, RS485
• Compatible with the Single Pair Ethernet connectors and cables

AUTBUS data networking and economic efficiency using the example of an e-charging station park.

In many e-charging station parks, the charging stations are networked with star-shaped Ethernet data cabling. A 16-port Ethernet switch, for example, is used as the central data switch. The energy manager, all e-charging stations and other IP-capable devices are each connected to the Ethernet switch with a data cable. If, for example, 10 charging stations, an energy manager, 2 surveillance cameras and possibly a router are to be connected, at least 14 data cables of different lengths are required.

If the charging station park is to be expanded, a new data cable must be laid for each additional charging station. Based on a simplified calculation with total cabling costs of 5 euros per metre of data cable laid, a distance of 5 m between the Ethernet switch and the first charging station, a distance of 2.5 m between the 30 charging stations in total, the installation costs for the 1238 m of data cable will amount to approx. 7000 euros. This also includes a second Ethernet switch, which has to be integrated after 15 charging stations, and 30 data cables, which are laid as a large bundle via a cable route.

Alternatively, users can install an AUTBUS data network and only need a high-quality, shielded and twisted 2-core data cable and connect the e-charging stations to an AUTBUS Ethernet converter ABN300 each. 78 metres of data cable and 30 AUTBUS Ethernet converters ABN300 are required for this. This results in total costs for laying the data cable and the AUTBUS ABN300 converters of approx. 3500 euros, which corresponds to a saving of 50% compared to Ethernet star cabling. If you want to retrofit more charging stations, you only need one approx. 2.5 metre long data cable and one ADM300 converter per charging station for up to 254 connected charging stations. If the two ends of the data cable are then connected with another data cable over the entire length, a data ring with increased reliability is created.

Summary

The AUTBUS ABN300 converter series is an optimised data communication solution, e.g. as a backbone data network for EV charging stations, PV systems and building automation.

• Cost savings result from the use of only one data cable and the resulting reduced installation effort, but also from faster commissioning due to reduced connection errors, which in turn reduces the need for specialised IT specialists.
• Longer system life is provided thanks to ring redundancy of the data network.
• Easy system expansion is achieved through cable extension and multidrop connections.

Technology report by KLG Smartec