As a major supplier of automation systems right across industry – not least to the automotive production sector – the product strategies adopted by German-owned multinational Siemens is bound to have significant potential impact on the shopfloor technologies used by manufacturing companies.
Siemens certainly thinks that is the case with two product announcements it made in the early part of this year – an enhanced Version 12 of its TIA (Totally Integrated Automation) Portal programming environment and a new generation of controllers for medium to high-end applications in the Simatic S7-1500 family.
The Simatic represents the latest step in a product evolution process that dates back to 1996. The TIA Portal concept is much newer – it was introduced as recently as 2010. Their importance to Siemens is explained by Simon Keogh, business manager for factory automation.
Keogh describes the TIA Portal as a “software framework for engineering all the aspects of the TIA”. It was launched with the aim of providing for the complete and easy integration of all the elements involved in constructing shopfloor automation systems.
Ease of use and the transferability of different program elements between application environments are fundamental elements of the whole TIA approach, and the new release aims to extend the reach of the concept, says Keogh. It originally encompassed just the HMI (human-machine interface) and the PLCs (programmable logic controllers) found on the shopfloor. “The TIA Portal now covers not just PLCs and HMIs but also SCADA (supervisory control and data acquisition) systems, drives and other peripheral devices,” states Keogh.
In practice, he explains, this means that users of the system can access a shared database and that program elements, even whole programs – which he terms ‘global library objects’ – created in one environment can be transferred to another by simple drag-and-drop routines. “The approach facilitates the re-use of any proven, tested piece of code,” he confirms. “A library object can be the entire application or anything associated with it.” While initial coding may take as long as previously, he adds, this pervasive ability to move different program elements between application areas and re-use them immediately should have major implications for time-saving in the programming of subsequent applications.
The extension of the concept into the drives environment – specifically Siemens Sinamics devices – represents a major development of the whole concept, argues Keogh. He points out that PLCs only deal with ‘set-points’ – most obviously ‘stop’ and ‘start’ signals to begin and end the operation of individual items of equipment. In contrast, the control systems of drives, precisely because real physical motion is involved, have to operate flexibly and in realtime. Now drives, despite their greater complexity, can be “parameterised in the same environment as HMIs and PLCs.”
Moreover, as Keogh explains, not only is ease-ofprogramming enhanced, but so are the overall diagnostic capabilities of the wider system, which means that both installation and maintenance operations can be supported in a more comprehensive manner. “You can now use the TIA Portal as a maintenance tool,” he states. Data gathering during installation and commissioning, for instance, will be “a lot more intelligent with a much greater ability to localise.” In practice what this means is that zeroing in on a specific error point, such as a broken cable, will be quicker and easier.
Meanwhile, the new range of controllers also promises not just an increase in capability but also in ease of use. An important point stressed by Keogh is that they can be programmed using any one of, or any mix of, five different coding languages including conventional ‘ladder logic’ and the type of more advanced structured languages with which, typically, today’s graduate recruits are more likely to be familiar.
Enhanced maintenance
As with the enhancements to the TIA Portal, Keogh says that this capability could have implications for the vital though all-too-often humdrum-seeming area of maintenance. He explains that by programming different operations controlled by the device in different ways, their accessibility by different types of staff could be better facilitated. As such, he states, the program elements that might need to be accessed by technician-level maintenance staff could be written in a simpler manner than the ‘background’ coding that would be the province of more advanced engineering personnel.
Interestingly, as well as being available in three versions defined by the type of processing unit they possess, the devices can also be configured if required in an ‘F’ or failsafe version for safety-related applications through enhancements in the areas of number of interfaces, bit performance, display size and memory capacity.
Another feature that Keogh highlights is that there is no need to program in diagnostic routines for the S7-1500 devices. Instead all the necessary instructions are written into the ‘firmware’ – essentially, the software is already loaded into the device before it reaches the user.
Security – in terms of protecting the knowledge that will be represented in the code on the PLC – also figures high in the specification for the devices. A key technique is that the memory card for each individual PLC can be made unique to that device so that if it is subject to unauthorised removal, no other device – not even another S7-1500 – can read it. It is therefore impossible, for example, for a rogue employee to steal crucial company-specific information on key production processes that may be stored on the card to enable its use in any form of pirate manufacturing.
Because it is a passive component of any automated manufacturing installation, cabling can often be overlooked as an area offering opportunities for process improvement. But a new approach from cable supplier Nexans is claimed to hold precisely such promise.
The company has expanded its Motionline range of cables for linking shopfl oor equipment such as robots through the addition of what it terms ‘hybrid’ cables which integrate power, data and signal transmission applications within a single outer casing. The cables are, however, not standard products and will instead be customised for specific applications according to requirements, says the company.
According to Jurgen Daut, European automation manager for the company, the new cable system does much more than offer the potential to make factory flors look neater by reducing the number of cables they carry. Daut says combining different types of application media within a single outer casing also means that the cables can be mated to equipment by single composite connectors.
In addition, and perhaps much more significantly, the fact that the cables carry digital rather than analogue signalling means that they allow different and more compact networking configurations. For example, instead of connecting robots to a central source of power and control in a star formation by means of multiple cables fanning out from a central unit, the hybrid cable approach enables sequential networking of the devices with just a single cable and connection.
Daut explains that the respective cabling, connector and labour costs for a cable harness for networking a piece of equipment, using conventional means, would probably be split on a 40-30-30 basis, while with the hybrid approach they would become 48-36-36 assuming the same unit of cost was involved. The older approach requires separate harnesses for both power and communications, so in reality the comparison is between 2x100 or 200 and 120, meaning that the hybrid solution should be 40% lower.
The capability to tie a memory card to a specific device in this way, Keogh confirms, has not been available with any other previous Siemens product, though he also stresses it is optional and can be turned on or off as required. It also, of course, can act as a safeguard against unauthorised alteration of the set-point information, whether accidental or malicious, something with obvious implications for the safe operation of equipment.
In short, both of these Siemens product introductions embody capabilities that not only make them appropriate for use in any single location but also, crucially from an automotive industry perspective, in globally distributed manufacturing environments.
Two capabilities seem paramount. The first is the ability to port code to drive specific manufacturing procedures from its original location and use it to drive exact replications of those procedures anywhere else without any need for reprogramming.
The second is the ability protect the intellectual property such code may represent from any unauthorised external use – an increasingly pertinent requirement as manufacturing starts up in locations with a relatively lax legal protection framework. Together, the two show how automation system providers are responding to the demands made by increasingly globalised manufacturing businesses.