CAN Data Loggers added to our product portfolio

Control Technologies UK Ltd is very pleased to announce that it is now the UK distributor for CSS Electronics and their range of CAN-bus data loggers.

CSS Electronics design and manufacture powerful CAN-bus analysers. The CLX000 range of products, now available in the UK through Control Technologies UK, combine stand-alone CAN loggers (8GB+) and real-time CAN interfaces. Already heavily used across a number of industries, including industrial, EVs, motorsports and automation, the CLX000 range offers a very flexible and capable CAN analysis solution. The series comes with an 8GB+ SD card memory (250M+ CAN messages) for recording data over long intervals. Further, the CLX000 also enables real-time streaming via Wireshark for diagnostics and reverse engineering. Finally, the WiFi auto-transfer option and compact size make the CLX000 loggers the ideal solution for low-cost and easy-to-deploy CAN loggers.

Control Technologies UK is a leading control systems integrator and solutions provider, specialising in CAN-bus based technologies. With over a decade’s experience in delivering end-to-end solutions to a wide range of industries, including off-highway, EVs, marine, renewables and many more, Control Technologies UK Ltd offers a unique engineering and systems solution. Control Technologies UK Ltd combines tried and tested design and development methodologies with cutting-edge hardware and a level of ingenuity. From system design through to software development, hardware design and integration to project management, Control Technologies UK is your one-stop-shop for a complete engineering solution.

At CSS Electronics, we help our customers deliver powerful insights, simply. To do so, we specialize in CAN-bus systems that are simple-to-use, yet configurable and powerful.
We design, test and support all our products from Denmark. Further, all our CAN bus devices are produced by our US partners to secure scale and flexibility. This lets us supply both single-unit quantities and mass-scale batches. As a result, our customers are diverse: From university motorsports teams needing a simple-to-use vehicle data logger to major global players seeking affordable CAN bus loggers for large-scale fleet optimization.

Mark Wood, Managing Director – Control Technologies UK Ltd, says “At Control Technologies UK, we are continually seeking out new technology to provide our clients with the best solutions. The CSS Electronics data loggers are the perfect mix of power and capability but at a low-cost – making them a most attractive solution for clients who want easily deployed, reliable data analytics. CSS Electronics share the same ethos as us – reliability, adaptable and rapid deployment and it’s great to have them as part of our solutions portfolio.”

Martin Falch, Partner – CSS Electronics says “We’re continuously looking to expand our network of trusted partners in key markets. The UK, in particular, is exciting with a fast-growing trend in industrial automation, fleet management and other applications where the CLX000 series is ideal. We are confident that Control Technologies UK Ltd is the right partner to engage local customers with a great level of professionalism – as well as providing vital feedback to our team so we can improve the series.”

Get in touch today for more information and to get the best price.

Getting started with CAN-bus

How to get started with CAN-bus

In this article we will outline what CAN-bus is, types of application and what you need to get started with a CAN-bus project.

What is CAN-bus?

CAN stands for Controller Area Network and it is a serial communications bus for bidirectional transmission of data for control systems. Connections between control units and input and output devices are typically made using a two-wire, twisted-pair cable and data rates of up to 1 Mb/s are possible, depending on bus length. CAN-bus is characterised by guaranteed latency and excellent error detection.

Originally developed for use in automotive applications to simplify and reduce wiring, the protocol has proven to be versatile and suitable for a variety of industries. Robert Bosch GmbH started developing CAN in the 1980s and Mercedes Benz was the first to adopt the protocol for a production vehicle in 1991. The protocol name is often written as CAN, CAN-bus, CAN bus and CANbus, but we use CAN-bus for consistency.

What types of application is CAN-bus used for?

Within an automotive application, which may be a car, truck or other vehicle, CAN-bus is typically used to connect electronic control units (ECUs) with almost any electrical or electronic device. This includes driving instruments, anti-lock braking system (ABS), engine- and transmission-related sensors and actuators components, electric windows, air conditioning, etc.

Because road vehicles are electrically noisy environments, CAN-bus has to be a robust and reliable communications protocol, while still achieving high performance. These characteristics, together with the low cost of the hardware, also make the protocol attractive for other applications, including off-highway vehicles, marine, medical, industrial automation and building information management (BIM) systems.


The latest version of the specification published by Bosch is CAN 2.0. This has two parts, with part A covering the standard format with an 11-bit identifier and part B covering the extended format with a 29-bit identifier. Because of this, a CAN device using 11-bit identifiers is commonly referred to as CAN 2.0A and a device using 29-bit identifiers is known as CAN 2.0B. The CAN standards and other specifications are freely available from Bosch.

In 2012, Bosch published an additional specification, CAN FD 1.0 for CAN with a flexible data-rate. This uses a different frame format that allows a different data length as well as optionally switching to a faster bit rate after arbitration (message prioritisation). CAN FD is compatible with existing CAN 2.0 networks so CAN FD and CAN 2.0 devices can coexist on the same network.

Following the initial work by Bosch, the International Organization for Standardization (ISO) published ISO 11898 in 1993. This was later restructured and it is currently a four-part standard:

  • ISO 11898-1:2015 Road vehicles – Controller area network (CAN) – Part 1: Data link layer and physical signalling
  • ISO 11898-2:2016 Road vehicles – Controller area network (CAN) – Part 2: High-speed medium access unit
  • ISO 11898-3:2006 Road vehicles – Controller area network (CAN) – Part 3: Low-speed, fault-tolerant, medium-dependent interface
  • ISO 11898-4:2004 Road vehicles – Controller area network (CAN) – Part 4: Time-triggered communication

This standard has also been adopted in some countries as a national standard so that, for example, in the UK it is published by BSI as a four-part British Standard BS ISO 11898.

Another two-part international standard relates to testing of CAN systems:

  • ISO 16845-1:2016 Road vehicles – Controller area network (CAN) conformance test plan – Part 1: Data link layer and physical signalling
  • ISO 16845-2:2014 Road vehicles – Controller area network (CAN) conformance test plan – Part 2: High-speed medium access unit with selective wake-up functionality

ISO 11898 and the Bosch specifications do not consider application layer protocols so, for example, automotive manufacturers tend to have their own standards and others have been developed for particular industries. Commonly encountered CAN-based higher-layer protocols include:

  • CANopen for industrial automation
  • DeviceNet for industrial automation
  • ISO Bus (ISOBUS), ISO 11783, for agricultural and forestry machinery (based on SAE J1939)
  • ISO-TP (Transport Layer), ISO 15765-2, for sending data packets and diagnostic messages over CAN-bus
  • SAE J1939 for buses and trucks originally, but now adopted more widely for diesel engine applications
  • NMEA 2000 (NMEA2k or N2K), IEC 61162-3, for marine sensors and displays in boats and ships (based on SAE J1939)

What types of CAN-bus are available?

As we have seen above, CAN-bus does not come in just one ‘flavour’ – there are many to choose from, so it is important to select the right one to suit your application. Here is a summary of the main versions and options:

CAN 2.0A – This type of CAN is sometimes called Classic CAN and uses 11-bit identifiers (referred to as ‘standard frame’). Compared with CAN 2.0B, CAN 2.0A has capacity for greater message throughout and shorter latency times. CAN 2.0A chips also cost less than CAN 2.0B chips.

CAN 2.0B – This is the ‘extended frame’ CAN protocol that uses 29-bit identifiers. Compared with CAN 2.0A, CAN 2.0B enables each message to contain more information but the downside is that more bus bandwidth is required.

CAN FD – As mentioned earlier, this is the version of CAN with a flexible data-rate. It uses a different frame format that allows a different data length as well as optionally switching to a faster bit rate after arbitration. By minimising latency, CAN FD brings CAN-bus closer to being a ‘real time’ protocol; data can be transmitted up to 30 times faster than with classic CAN-bus. In addition, CAN FD holds a maximum of 64 bytes of data per frame whereas classic CAN-bus only holds 8 bytes per frame. For CAN FD to operate reliably at high speeds, line parasitic capacitances have to be reduced, so components on the line must all be suitable for use with CAN FD.

CANopen – Not quite the same as CAN 2.0A, CAN 2.0B and CAN FD, CANopen is a communication protocol and device profile specification for embedded systems used in industrial automation and similar applications. Standards and specifications are published by the organisation CAN in Automation (CiA); these cover an addressing scheme, communication protocols and an application layer defined by a device profile. Note that the lower level protocol implementing the data link and physical layers is usually CAN-bus, but the CANopen device profile can also be implemented by devices using other means of communication such as Ethernet Powerlink and EtherCAT.


CAN-bus is a multi-master serial bus so microcontrollers and devices can communicate without a host computer. Each node on the network can be a microcontroller, embedded computer, I/O device or gateway that enables networked devices to interact with something else (for example, a computer or a non-CAN-compatible I/O device, typically via an Ethernet or USB connection).

Nodes are connected using shielded two-wire, twisted-pair cabling (120Ω nominal).

High-speed CAN networks (ISO 11898-2) use a linear bus terminated at each end with 120Ω resistors. In contrast, low-speed (fault-tolerant) networks (ISO 11898-3) feature a linear bus, star bus or multiple star buses connected by a linear bus. Each node is terminated by a fraction of the overall resistance, which should be approximately 100Ω but not less than 100Ω.

Each node on the network comprises:

  • CAN transceiver for transmitting and receiving data streams
  • microcontroller (central processing unit, microprocessor or host processor) for interpreting messages and determining what messages are to be sent
  • CAN controller (often integral with the microcontroller) for receiving and assembling data bits from the network and for transmitting data bits after receiving messages from the microcontroller

Higher-level control devices and I/O devices are connected to the microcontroller.


The CAN-bus protocol can be considered as a series of abstraction layers:

  • application layer
  • object layer
  • transfer layer
  • physical layer

The application layer is not covered by the CAN standards but, instead, is addressed by other standards and specifications, often industry-orientated (eg SAE J1939, CANopen and DeviceNet). The other layers are outlined below.

Object layer – deals with message filtering and message and status handling.

Transfer layer – this moves messages between the physical layer and the object layer. The transfer layer lies at the heart of the CAN-bus protocol and performs a wide variety of tasks, including bit timing, synchronisation, message timing, arbitration, acknowledgement, error handling, transfer rate and timing, and information routing.

Physical layer – whereas other layers exist in software, the physical layer predominantly concerns electrical and mechanical aspects. ISO 11898-2 specifies the voltage, current and number of conductors, but not the connector type, colours, labels and pin-outs. These therefore vary between different applications, even to the extent that some users (eg in the automotive industry) have custom connectors that incorporate CAN-bus pins alongside others for different functions. However, many CAN-bus applications utilise standard 9-pin D-sub connectors.


CAN-bus has two frame formats:

  • Standard (base) frame format (CAN 2.0A,) supporting an 11-bit identifier
  • Extended frame format (CAN 2.0B), supporting a 29-bit identifier comprising an 11-bit identifier plus an 18-bit extension

A base frame message is recognised from the dominant IDE bit, while an extended base frame has a recessive IDE bit. CAN-bus controllers that support the extended frame format can also send and receive messages in base frame format.

In addition to the two different frame formats, there are four types of CAN-bus frame:

  • Data frames contain node data for transmission
  • Remote frames request the transmission of a specific frame identifier
  • Error frames are transmitted by nodes detecting errors
  • Overload frames inject a delay between data or remote frames

Starting a CAN-bus project

The bare minimum for starting a CAN-bus project is a CAN-bus controller, compatible cabling and one or more CAN-enabled I/O devices. CAN-bus controllers can typically be programmed in C, but Matlab and Labview are popular alternatives, and CODESYS is an option for some controllers. Various libraries – for example, for CANopen, J1939 and error handling – can simplify programming and save time. The programming software will usually be run on a PC that can be connected to the controller for uploading the program.

Pros and cons of CAN-bus

First of all, the pros:

  • CAN-bus systems allow data transmission at up to 1 Mb/s (or >2 Mb/s for CAN FD).
  • As a distributed system, it reduces wiring, cost and complexity, and enhances overall system capabilities and performance.
  • Easy integration – because there are so many CAN chip manufacturers who provide the data and physical layer, all the software developer needs to do is to write the code for the application level.
  • Robust EMC protection – CAN-bus operates in difficult electrical environments and ensures noise-free transmission.
  • Traffic congestion is eliminated because the messages are transmitted based on their priority, so the entire network can meet the timing constraints.
  • Error-free transmission because each node can check for errors during the transmission of the message and send the error frame.

However, CAN-bus is not ideal for every application:

  • In most cases a maximum of 64 nodes can be supported.
  • Networks can only operate over distances of up to 40m with data rates of 1 MB/s (5 km is possible but data rates are reduced to 10 kB/s).
  • There can sometimes be undesirable interactions between nodes, and the topology must be designed with care to minimise stubs.

Common myths and misconceptions about CAN-bus

Can-bus is often viewed as a low-cost, widely used and easy-to-implement protocol but that does not mean it is as simple as plug-and-play. It is definitely true that care must be taken when designing and implementing a CAN-bus system, otherwise problems can arise. It is vital that OEMs understand the implications of ISO 11898 on their wiring designs.

CAN is fault tolerant, and more so than most other communications protocols, but there are limits to the fault tolerance. If the operating environment or the wiring is electrically very noisy, then the CAN-bus will shut itself down due to a build-up of error frames. Just because CAN-bus is fault-tolerant, it does not mean that it can cope with a multitude of sins on the physical side. This is particularly relevant with electric vehicles.

Real-world CAN-bus systems

Control Technologies UK is a CAN-bus specialist with many years of real-world experience with control systems, helping companies from multiple industries to leverage greater functionality, efficiency and cost savings. Whether you are looking for real-time distributed control, remote data retrieval and analytics, intuitive visualisation or need support to improve the performance of an existing CAN-bus system, our team is available to provide advice and engineering. We work closely with a network of leading manufacturers and technology partners, ensuring that customers benefit from the most relevant solution to their CAN-bus challenges. Overall, we offer the most complete end-to-end service, extending your engineering capabilities without extending your overheads.

Contact us to discuss your CAN-bus and control system requirements.


Our Team has grown!

Control Technologies UK continues to go from strength to strength with the addition of a dedicated Applications Engineer.

Matt Joy has joined the team fresh from the University of Sheffield where he successfully completed an MEng in Mechatronic and Robotic Engineering. Matt is a very accomplished embedded systems engineer, with a wide range of skills including control theory, system design, and software development.

As Mark Wood, Managing Director, says “This is a significant and exciting milestone for the company; Matt brings with him a wealth of technical abilities that will significantly enhance our engineering offering to clients and partners. Matt is already working on customer projects, after just 3 weeks in the job, and I’m sure our customers will get to know him over the coming weeks.”

Control Technologies UK is a leading systems integrator for the mobile and off-highway machinery market. Our wide range of technical services enables OEMs to embrace new and innovative technologies to increase functionality, reduce cost and extend the overall life of a machine.


Our Training & Consultancy Services

Control Technologies UK offers bespoke training and consultancy solutions to customers looking to increase internal knowledge and capabilities. We understand that having the right skills internally are vital for a business to grow and support the machines out in the field. This is why we now offer custom training and consultancy services to help you realise your system requirements.

The training can be anything from principles of CAN through to electro-hydraulic control. Essentially the course should focus on distributed control solutions, but can be about all aspects of the system from design through to development and testing, on to sales and beyond.

If this is of interest, please head over to our Training page to find out more and make contact.

We look forward to working with you in the future.


A brief introduction to CAN-bus

pcb, technology, CAN-bus

CAN-bus is one of those technologies that everyone experiences every day, without actually knowing about it. Because it is so widely used, in everything from cars and trucks through to boats, factories and even building management systems, the chances of interacting with it on a daily basis are pretty high. But what is CAN-bus and how can it be implemented?

To understand what CAN-bus is, we need to understand why it was created in the first place. Back in the early 1980s cars were becoming more and more complex and the size and complexity of the traditional communications and wiring systems was getting out of hand. To counter this, engineers at Robert Bosch GmbH began development of a serial communications system to allow a more distributed control network and a reduction in the general wiring architecture and complexity. As a result of this development, the first vehicle, a Mercedes S-Class, rolled of the production line with 5 on-board control units communicating over CAN in 1991. Very quickly CAN was adopted in pretty much every engine control system of top-range European vehicles. Since that point CAN has gone on to be the standard in the automotive world and widely used in industrial applications.

What is CAN-bus?

  • CAN stands for Controller Area Network
  • CAN is a vehicle bus standard designed to allow microcontrollers and devices to communicate with each other in applications without a host computer. It is a message-based protocol, designed originally for multiplex electrical wiring within automobiles, but is also used in many other contexts.
  • As an alternative to conventional multi-wire looms, CAN Bus allows various electronic components (such as: electronic control units, microcontrollers, devices, sensors, actuators and other electronic components throughout the vehicle) to communicate on a single or dual-wire network data bus up to 1 Mb/s
  • CAN is a multi-master network that uses message priority (arbitration)
  • Robust and fault tolerant – designed for high EMC environments (protected by twisted pair and shielding)
  • Capable of up to 5KM @ 10kbit/s and as low as 40M @ 1MBit/s (baud rate)
  • Internal fault mechanisms (error frames)
  • Data exchange between any CAN participants, field devices and process control computers
  • System-wide data consistency
  • Reduced bus load through data preparation
  • Real-time thanks to guaranteed latency time
  • Standardised by ISO-11898

Benefits of using CAN-bus

  • As a distributed system, it reduces wiring, cost and complexity and enhances overall system capabilities and performance
  • Easy integration – because there are so many CAN chip manufacturers who provide the data and physical layer, all the software developer needs to do is to develop the application level code.
  • Robust EMC protection – It provides the ability to work in difficult electrical environment and ensures noise free transmission.
  • Traffic congestion is eliminated as the messages are transmitted based on their priority and it allows the entire network to meet the timing constraints.
  • It provides for error free transmission as each node can check for errors during the transmission of the message and send the error frame.

CAN and Control Technologies UK

So where do we come in? We have over 10 years experience working with CAN and designing and implementing systems with it. From agriculture, via ground support equipment to electric vehicles and trains, we’ve worked on some pretty complex applications. Through our work with CAN we’ve learned what does and doesn’t work and are able to work closely with our customers to ensure that CAN is applied correctly or assist when things aren’t quite right. We’ve work with a wide range of hardware partners and we are extremely capable of implementing CAN in all it’s forms.

If you are embarking on CAN implementation, tasked with supporting an existing CAN system or looking for someone to develop a complete end-to-end solution, we can help. If you’re looking for a complete solution we offer a no-obligation 2 hour workshop with your key personnel to explain the benefits and technology behind CAN, understand your requirements and discuss possible solutions. If you want to know more, please get in contact.


And we have lift-off!

Control Technologies UK Ltd has been launched to provide independent control and monitoring solutions to mobile machine OEMs. The company has been founded by Mark Wood, a 10-year veteran of the control system industry in the UK having previously worked for Sensor-Technik UK, ultimately as UK and Ireland GM for 6 years. Mark brings with him a wealth of technical experience in CAN-bus and distributed control systems, as well as project management and business development.

Mark Wood, Managing Director, says “As modern machine and end-user requirements become more complex, OEMs are increasingly reliant on technology to remain competitive. My company acts as the ‘interface’ between the latest technology and industry, working closely with OEMs and end-users to understand their requirements and deliver the best possible solution. We are unique in that we provide the customer an independent solution and long-term technical support. If a customer does not have the time or technical capability to source the most appropriate solution, that’s where we come in. Ultimately we want our customers to realise the benefits that technology provides.”

Whether you are looking for an electro-hydraulic control solution, remote data analytics and service tools or a complete control solution, Control Technologies UK can take responsibility for the whole thing, leaving the OEM to focus on what it does best. Control Technologies UK has experience delivering systems across a wide-range of applications, from electric vehicles through to agriculture and marine. Additionally, Control Technologies UK can act as a technology consultant, helping customers to on-board innovative technologies, through training or remote support, to extend their own engineering capabilities.

The company aims to provide the most appropriate technical solution within the customers budget. Control Technologies UK acts either as an extension of an OEMs own engineering capabilities, or as a standalone solutions provider. By working with industry-leading manufacturers, Control Technologies UK offers the most up to date and cost-effective solutions.