by Randy Durick, VP, Network & Interface Div., TURCK
Automation component manufacturers shrink I/O blocks to meet growing demand for compact systems
A Midwest automated machine builder had an installation problem on the factory floor. A new machine was a perfect solution to the space and efficiency demands of its customers. But to make it work in the space the company had, a new I/O block approach was necessary. A standard-size module wouldn’t work, and the number of cables and enclosures required as a work-around was too cumbersome and inefficient.
After calling its supplier, the company found a small-scale digital I/O module that was suitable for compact applications. It not only fit the space, but also streamlined the number of cables and connections required because the block connected directly to the controller for power and communication. This direct link made installing and changing the machine tools easier.
Many OEMs and machine builders have found themselves in similar predicaments over the years. Thankfully, factory automation component manufacturers are stepping up to solve these issues by shrinking the size of I/O block technology.
Trending toward smaller
Automation is on the rise as manufacturers and OEMs are relying more heavily on automation for tasks that used to be performed by people. In the automotive industry, programmed robots have taken over welding responsibilities. The packaging industry has undergone similar changes—instead of packaging pallets by hand, measuring and weighing systems are automated to perform these duties.
Machines on the plant floor have evolved along with these manufacturing processes. In many instances, tasks that used to require a large machine and 10 workers have been replaced by a smaller crew of operators and smaller machines. Space is at a premium with these more compact machines and diminished footprints.
A secondary trend is the adaption of existing processes to meet custom requirements. For example, you might need to expand control options to fit new customer needs. If the control cabinet is full, I/O blocks placed outside the cabinet can add functionality. Similarly, with more operations looking to phase out the cabinet altogether, smaller on-machine solutions are desirable where there isn’t a lot of space. This requires creativity for where to place the block, and compels automation component manufacturers to think small.
Technology advances benefit engineers
Technology is now at a point where automation component manufacturers can meet these demands put forth by engineers. Specifically related to I/O blocks, advances in microprocessors, Ethernet switches and connectors have helped shrink the physical size of these devices.
Computer technology has been shrinking ever since the first processors were developed. What used to take hundreds of square feet of space has been upgraded and downsized to fit well within the palm of your hand or even on your fingertip. Component manufacturers have taken advantage of these changes by creating products that can do more with less space. Looking at I/O modules, smaller and more powerful microprocessors—across memory, size and clock rate specs—provide advanced functions and direction within the block without requiring additional millimeters. Prices on processors continue to fall as the market expands, which benefits engineers looking to upgrade technology without increasing budget.
Other technological advances have been realized with Ethernet switches and connectors. Smaller connectors with advanced communication capabilities allow the I/O block to have a smaller physical size while not sacrificing port count. By fully embedding the Ethernet switch, engineers have more flexibility to position the I/O module as needed while maintaining the small block footprint.
Further shrinking the footprint
A standard structure with I/O module technology is to link the block to a bus coupler or gateway, which then communicates to the PLC master and any additional I/O extension modules. These closed architectures require that all components speak the same protocol. Typically, bus couplers cost about three times as much as extension modules, and also require additional space for the couplers and gateways.
Some microprocessors have the ability to smartly process different Ethernet signals, entirely eliminating the need for a gateway and proprietary subnet. These microprocessors immediately recognize and communicate different protocols—whether it’s Ethernet/IP, Modbus TCP or Profinet—and communicate on that same protocol. This further shrinks the footprint of on-machine technology (especially when you consider that some gateways can be larger than the I/O block itself) and simplifies topology. These streamlined modules also save on cost, consolidate product count and simplify integration, as one I/O block can be ordered and specified for different protocols within the same system and/or company.
Implementing smaller I/O blocks into applications
Smaller I/O blocks are ideal for OEM equipment manufacturers and small- to medium-size machine builders. Machine builders for the semiconductor industry are a great example of how smaller technology helps them meet customer demand.
Semiconductor manufacturers work within a highly regulated environment, and their machine builders need to offer systems that respond to their detailed requirements. But it can be expensive to entirely change a manufacturing or machine building structure. These OEMs need to have the flexibility to modify standard equipment to meet custom requirements and keep their customers happy. Enter the small I/O block.
Let’s say the machine builder’s current system can account for up to 90% of the needed design from its template. Instead of taking on the cost to re-engineer the machine for each customer based on their different needs, the builder could install a small I/O block on the network to control measurement points and more easily create the tailored solution for the customer. And when the small I/O block smartly recognizes a number of Ethernet protocols, the flexibility is further enhanced.
Beyond these benefits, smaller I/O blocks with built-in protocol recognition easily integrate into existing systems. Instead of reconfiguring your topology to account for a new gateway, these smart modules are simply incorporated into star, daisy chain or ring topologies without interruption or complex feats of engineering.
Designs will continue to evolve
Delivering small solutions is a big win for the industry and an ongoing trend that will carry into the future. As advances in technology enable automation component manufacturers to further shrink the size of I/O technology, the benefits will continue to mount for OEMs and machine builders in search of flexible, small systems.
Analog block advances
The diminishing size of I/O block technology is not limited to digital modules, although these are more common. Analog options are also available to determine the precise condition or state of a component. There are numerous automation applications that rely on analog data input for operations, including gathering temperature readings and position sensing to determine exact location. As an output, these modules can be used to control a final control element or positioner.