Cube67: Probably the Best I/O System in the World!
Colin Cartwright
Supercharging machine builders with simplified control systems that short-circuit their competition!
Managing high-density I/O on complex machines is one of the most time-consuming and error-prone aspects of control system installations. Traditional systems often require extensive wiring, multiple IP addresses, and usually have very limited diagnostics that can't be seen outside of the cabinet— all of which slow down installation, commissioning, troubleshooting, and future upgrades.
As machines become more advanced and production timelines tighten, many of the machine builders and integrators I work with are looking for smarter, more scalable solutions that reduce labour, simplify commissioning, and make long-term maintenance easier.
The Cube67 I/O system from Murrelektronik is designed with exactly these challenges in mind, and for high-I/O-count applications, it continues to stand out as one of the most robust and flexible options available.
What makes the Cube67 system stand out is how it tackles common I/O system challenges: it handles power and data over a single cable, supports both star and line topologies, and consolidates all your I/O under a single IP address - even if you have more than a thousand I/O points!
Cube67 also offers more than 150 module options, including several specialized modules for IO-Link, analog signals, thermocouples, RTDs, RS232/485, MoviMot, etc. Plus, there is an optional Diagnostic Gateway module that provides a complete graphical representation of the whole I/O system, including the status of every I/O point. It also includes OPC UA connectivity for those looking for extended data.
I won’t be getting into all the technical specifications of Cube67 in this article, but we’ll explore what it brings to the table in value, why the machine builders and integrators who’ve used it love it, and why I think it’s probably still the best fieldbus system in the world.
Overview of the Cube67 Concept
Cube67 is a modular I/O system designed for distributed installations. It places I/O modules directly alongside sensors, actuators, and other devices on the machine, minimizing the need for large control cabinets or extensive parallel wiring. A single cable carries both data and power from a bus node to multiple modules, simplifying installation and maximizing uptime. In addition to IP67-rated modules for harsh environments, Murreletronik also offers IP69K Hygienic Design variants suitable for food and beverage applications.
This distributed approach provides:
These aspects streamline control system installations and reduce total costs from electrical design through maintenance.
Single-Cable Technology for Data and Power
One of Cube67’s core efficiencies lies in its single-cable design, which supplies both power and communication. This approach contrasts with systems that require separate power and data cables. By merging both into a single cable, Cube67 helps prevent incorrect connections, streamlines installation and reduces cable quantities by up to 50% in most cases.
Using a single system cable also simplifies expansions and reconfigurations. Users can attach additional modules anywhere they want without routing separate cables back to the cabinet. This cuts both material costs and labour time, which is particularly useful in complex machinery or when space is constrained.
Decentralized Architecture and Flexible Topology
Traditional centralized I/O can result in large bundles of cables running from every device back to one central cabinet. In contrast, Cube67 employs a decentralized layout with modules located at or near the devices they serve. This structure is suitable for projects where sensors and actuators are dispersed across large or complex machines.
Cube67 also allows flexible topology design, including daisy chain and star configurations. Up to 60 meters of system cable can be distributed per bus node, with branching possible in four directions. This adaptability helps electrical designers position modules exactly where they are needed, minimizing cable runs.
For example, on a food & bev project, a designer might place IP69K modules on one branch in the wet zone while another branch is taking care of all the I/O with IP67 modules in the dry zone, yet both zones remain connected to the same Cube67 bus node. The Cube67 system supports up to 32 modules per bus node, allowing a wide range of layouts and configurations.
Multi-Functional I/O Ports
A major feature of Cube67 is the multi-functional channel design. On many modules, each I/O point can serve as a configurable input or an output. This capability helps standardize module types, reducing the variety of components you need to stock. In practice, if you need more inputs on one part of your machine, you can reconfigure spare output channels as inputs. Conversely, if you need additional outputs, you can reassign input channels.
This feature simplifies machine retooling or expansions:
At many machine builders, machine requirements change quickly, especially if you build custom machines for multiple customers. The ability to repurpose modules provides more flexibility and prevents unnecessary rewiring or replacement.
Rugged IP67 and IP69K Options
The harsh operating conditions in many industries—such as automotive, food processing, and packaging—require solutions that can withstand dust, vibration, moisture, and other environmental factors. Cube67 modules are fully potted, carrying an IP67 rating. They can be placed directly on machines rather than confined to an enclosure. This approach eliminates bulky junction boxes and helps reduce the number of cables returning to the control panel.
For highly sanitized CIP environments, Cube67 Hygienic Design modules meet IP69K standards and are suitable for direct washdown areas. These stainless-steel modules feature sealed housings designed without crevices or niches, making them easier to clean and less prone to contamination. The ability to replace large, expensive stainless-steel enclosures with compact distributed modules can significantly reduce both material and labour costs.
Seamless Integration of IP20 I/O
While Cube67 thrives in decentralized, connectorized installations, there are still times when traditional IP20 I/O is required—particularly during retrofits, machine upgrades, or when working with legacy devices that still rely on individual wires.
Rather than force machine builders to choose between two incompatible architectures, Cube67 offers a seamless way to integrate IP20 I/O directly into the distributed Cube67 system. Murrelektronik provides interface modules that connect DIN rail-mounted IP20 terminals to the Cube67 backbone, allowing all I/O—connectorized or wired—to coexist on the same system.
This hybrid capability is especially useful in scenarios such as:
By allowing Cube67 to interface with IP20 terminals, you preserve the advantages of decentralized architecture while accommodating the real-world complexities of brownfield environments.
Most importantly, this isn’t a bolt-on workaround—it’s a fully integrated solution. IP20 connections are managed under the same bus node, share the same diagnostics, and appear in the same PLC data structure as the rest of your Cube67 modules. There’s no duplication of effort or parallel programming required.
This hybrid flexibility is something few, if any, I/O systems offer. It provides another layer of adaptability for machine builders who want to modernize without starting from scratch—and gives controls engineers a practical way to blend old and new technology under a single, intelligent I/O system.
Protocol Independence
Machine builders typically have to support multiple communication standards depending on end-customer specifications. The Cube67 modules are protocol-agnostic, requiring only a change of one component (the bus node) to convert from EtherNet/IP to ProfiNet or EtherCAT. The downstream I/O modules remain unchanged.
This “Change the bus node, not the system” principle simplifies machine design for OEMs that ship to customers using different PLC platforms. It also future-proofs installations: if the facility transitions to a new fieldbus or industrial Ethernet protocol, they can retain the majority of the distributed I/O network and simply replace bus nodes.
Detailed Diagnostics and Diagnostic Gateway
It’s good practice for machine builders and controls engineers to minimize downtime if something goes wrong. When an issue occurs, quick diagnostic identification is essential for swift resolution. Cube67 provides in-depth diagnostic data at the port and channel levels. LED indicators on each module can provide local fault information, while status and diagnostic signals can be communicated through the network back to the PLC.
For more extensive visibility, the Cube67 Diagnostic Gateway module provides a centralized interface for the entire system:
This approach offers major benefits at all stages: from commissioning to routine maintenance to long-term data analysis.
IO-Link Integration
Smart sensor technologies are increasingly common in modern machinery, enabling advanced condition monitoring and configuration. Cube67 IO-Link modules enable you to connect up to 128 IO-Link devices per bus node, significantly expanding smart sensor and actuator capabilities. IO-Link’s standardized communication simplifies device parameterization, diagnostic data exchange, and device replacement.
With IO-Link, controls engineers can achieve:
By coupling IO-Link with multi-functional channels, machine builders can create flexible, data-rich I/O systems that are quick to install and easy to maintain.
Machine Option Management (MOM) for Modular Systems
Another valuable feature of Cube67 is Machine Option Management (MOM). This function lets users enable or disable separate modules (and, by extension, machine segments) via the PLC. This can be particularly beneficial in:
By centralizing these options in the PLC program, controls engineers can reduce reconfiguration time. This supports faster changeovers and helps standardize documentation across various machine configurations.?
Simplifying High I/O Counts
Machines with a higher density of I/O can be difficult to set up and manage. Using a central control cabinet packed with dozens of I/O modules often leads to bigger cabinets, cluttered wiring and higher installation costs. This level of complexity can be especially frustrating when you need to expand or modify your machine later. Regular standalone IP67 modules are mostly limited to 16 I/O signals, with each module adding an IP address to your system. When you get to hundreds of I/O points, this gets costly and adds complexity. Yes, you can use IO-Link masters with hubs, but this introduces its own problems, which we will discuss later in this article.
Cube67 addresses all of these headaches with a single IP67-rated bus node that can handle hundreds or even thousands of I/O points on a single IP address. Yes, you read that right - One IP address! Unlike other I/O systems that require a unique IP address for every I/O block, you only need to assign one IP address to the Cube67 bus node and then connect up to 32 I/O modules wherever they are needed. This approach keeps your IP count lower and your network simple, making both initial configuration and future expansions much easier.
Food and Beverage Applications
Cube67’s optional IP69K hygienic modules work well in food, beverage, and other washdown-heavy environments. In many cases, you can eliminate large stainless-steel junction boxes simply by using sealed machine-mount modules. That leads to fewer enclosures and less wiring overall.
By placing Cube67 modules close to sensors in a washdown zone, you avoid running each sensor cable back to a Nema 4 junction box or central cabinet. If you need to add a new sensor or actuator, you just plug it into the nearest vacant port. If something goes wrong, built-in diagnostic LEDs and Diagnostic Gateway alerts help you pinpoint the issue quickly.
Specialized Modules for Thermocouples, RTDs, and Analog Signals, etc.
Many distributed I/O solutions excel at digital signals but offer fewer options for analog or other types of traditional I/O signals, like temperature measurements. By contrast, Cube67 includes specialized modules for MoviMOT, thermocouples, RTDs, and analog signals (voltage and current). This is especially helpful if you’re handling temperature-sensitive processes in sectors like food and beverage or packaging or if you need high-precision analog readings from flow meters or pressure sensors without pulling separate shielded cables for each device back to the main panel.
Placing these modules on the machine, rather than in a central cabinet, can also reduce signal degradation over long cable runs and simplify your installation by removing the need for standalone signal conditioners.
A Better Option Than IO-Link Master-to-Hub Setups
IO-Link technology has gained recognition by facilitating advanced communication with sensors and actuators. Yet, many machine builders utilize IO-Link “master-to-hub” I/O architectures, which are not necessarily the intended application for IO-Link. In such setups, each IO-Link master manages one or more hubs that are used to connect multiple I/O devices. Higher I/O counts usually mean multiple IO-Link masters and hubs, leading to more IP addresses, complex configurations, and extended PLC addressing.
In contrast, Cube67 avoids these complexities by consolidating the entire system under one device and one IP address. Its structure is inherently more direct to commission and troubleshoot because every I/O channel resides in a single, decentralized network. When an issue arises, controls engineers consult one diagnostic environment rather than the diagnostic logs on numerous IO-Link masters. For those still wanting the advantages of IO-Link, Cube67 offers IO-Link modules that integrate seamlessly into the Cube67 system and enable 128 IO-Link devices to be connected to one IP address. To the best of my knowledge, there is no other I/O system in the world that can do that! This means you can benefit from all the smart features of IO-Link—remote configuration and enhanced sensor data—along with the functionality of traditional analog signals and standard digital signals under one system and one IP address.
Industry 4.0 and Data Transparency
As more facilities adopt Industry 4.0 practices, advanced data handling becomes important for predictive maintenance, performance optimization, and overall equipment effectiveness (OEE). Cube67 is designed with digitalization in mind:
This data visibility contributes to ongoing operational improvements and helps align machine performance with business goals.
Commissioning and Maintenance
Because Cube67 uses one IP address for all connected modules, you only have to configure a single device in your PLC or control system—bus nodes are available for most major protocols, including EtherNet/IP, EtherCAT and ProfiNet. Once the bus node is in place, adding or removing I/O modules is straightforward, and the platform’s diagnostic features help you validate your layout during commissioning.
Maintenance benefits come from the integrated channel-level diagnostics and, if implemented, the Diagnostic Gateway. If you need to troubleshoot or replace a module, you can do so at the machine level instead of disassembling or tracing wires in a large cabinet.
Lower Total Cost of Ownership (TCO)
Lowering the Total Cost of Ownership (TCO) is fundamental for successful machine building and long-term operational efficiency. Cube67 delivers cost benefits at multiple stages—from initial design to future expansions—ensuring that capital investments yield strong returns. Below are four key areas where Cube67 helps machine builders maintain a competitive edge while enhancing system performance.
1. Simplified Planning With a decentralized approach, control system designers can scale each machine section as needed instead of routing all signals to a central panel. Using standard modules that can act as either inputs or outputs further eases initial design tasks. Fewer specialized part numbers reduce complexity in procurement and inventory.
2. Faster Installation The single-cable concept and plug-in connections cut installation times significantly. Cable routing is simpler, and fewer terminations reduce error potential. By placing I/O modules near the devices they serve, you reduce cable runs and potential wiring mistakes.
3. Shorter Commissioning and Reduced Downtime Diagnostic features—especially the Cube67 Diagnostic Gateway—allow controls engineers to see exactly which channel has a fault. This capability also reduces commissioning times by making it easier to spot miswired or underperforming devices. During operation, the same diagnostics minimize unplanned downtime by providing quick fault isolation.
4. Easy Reconfiguration and Protocol Flexibility When product lines expand, or the facility switches controllers, Cube67’s protocol independence avoids large-scale rewiring. The ability to reassign I/O channels and add or remove modules keeps future retooling costs down. This adaptability supports ongoing machine evolution without sacrificing performance.
By streamlining design, speeding up installation, reducing commissioning time, and accommodating future changes in protocol or machine configurations, Cube67 proves its value throughout the life cycle of any automation system. These benefits not only cut costs but also enable faster responses to market demands and technical challenges, positioning Cube67 as a forward-looking, cost-effective choice for machine builders and controls engineers.
Real-World Success Stories
On paper, all this looks promising, but real-world examples often carry more weight than theory. The following cases highlight Cube67 in action.
1. 120 Drives on a Pallet Conveyor In one food and beverage project, a major company needed to control 120 drives in a pallet conveyor system. Traditionally, you might see separate cabinets for each conveyor zone or multiple IP addresses to handle the I/O for that many motors. With Cube67, however, the engineering team ran a single trunk cable around the conveyor line, attached local modules for sensors and drive feedback, and kept the entire system under one IP address. This approach shortened the installation schedule, simplified future expansions, and made troubleshooting far more direct.
2. Machines with Constantly Changing Configurations From time to time, you’ll see machine builders who specialize in highly customized or frequently varying designs. Murrelektronik shared an example titled “Counting on the Cube67—When Every Machine Is Different,” highlighting how easily modules can be added or repositioned along a single trunk cable. Instead of redesigning each machine’s wiring from scratch, engineers simply attach the necessary I/O blocks and maintain the same overall structure. This reduces engineering overhead and keeps lead times predictable, even as customers request machine modifications.
3. Hermle’s Modular Machine Tools Hermle is known for producing CNC machining centers that often require precise, high-speed I/O for sensors, coolant systems, and tool management. They use Cube67 to locate modules directly where signals are needed on the machine, cutting back on cables and simplifying maintenance. By distributing I/O in tight, sometimes wet environments, Hermle can keep machines compact and operator-friendly.
More Than One Million Modules in Operation
With over one million Cube67 modules installed worldwide, this fieldbus system has established a strong track record of performance and reliability. Machine builders in many countries and across multiple industries have standardized on Cube67 for its combination of:
Its proven success underscores Cube67’s ability to solve real-world automation challenges in sectors ranging from automotive and food & bev to packaging and logistics.
Conclusion
In an industry that demands agility, reliability, and clear data insights, Cube67 surpasses many expectations. Its decentralized design eliminates the extensive wiring challenges that have long posed issues for machine builders. By integrating data and power in one cable, offering advanced IO-Link integration, delivering robust diagnostics, and maintaining protocol independence, Cube67 proves itself as both an immediate and a future-ready solution.
Yet, Cube67’s real power is in how it addresses core pain points—cabling complexity, prolonged commissioning, and confusing troubleshooting. Unlike certain IO-Link master-hub setups that often involve more cabling, extended addressing, and multiple IP addresses, Cube67 consolidates these demands into a single system interface. Maintenance technicians appreciate the concise network overview and localized indicators, while controls engineers benefit from an architecture that is easy to modify for additional I/O or protocol shifts.
If your objectives include simplifying control systems, reducing the need for skilled labour, faster electrical installations, minimizing downtime, and guaranteeing the long-term adaptability of your machines, Cube67 is a compelling contender. It is a proven system engineered for industrial realities while also offering the convenience and accessibility demanded by modern manufacturing. Put simply, it’s probably the best fieldbus system in the world for machine builders looking for an efficient and future-proof way to manage distributed I/O.
About the Author: Hey there! I'm Colin, and I've worked with industrial automation and control systems for over thirty years. I’m passionate about simplifying control system installations and commissioning processes. I enjoy working with machine builders and OEMs to reduce skilled labour challenges, improve machine OEE, and boost ROI.?
Want to see how we can work together? Connect with me!