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Motor management and ATEXManaging motors for efficiency and reliability can be a headache at the best of times, and new EU regulations on explosive atmospheres won't make it any easier. According to some estimates, 50% of all industrial applications contain a hazardous area of one kind or another, ranging from small mixing applications to the largest petrochemical complex. If your company handles materials that can cause flammable vapours or dust, the ATEX directives 95 and 137 affect you. Implemented in the UK as the Dangerous Substances and Explosive Atmospheres Regulations (DSEAR), this new legislation aims to ensure that only equipment with specific safety features is used in areas that could, potentially, contain flammable atmospheres. Designed to regulate the use of equipment in potentially explosive atmospheres, the two ATEX Directives became law throughout the EU in July 2003. And this time, it is not just manufacturers who must comply. Any company that employs staff in potentially explosive atmospheres must take specific steps to protect them. It means that motors and other equipment on the market from this date have to comply with the ATEX regulations. So, managing motors under the new ATEX regulations is not daunting - just follow a few basic rules, keep the deadline in sight and for most users it will be plain sailing. Unfortunately, far from all users are aware of the changes. In particular, many users seem to have overlooked the existing plant. This also falls under ATEX and it is the end user's responsibility to ensure it is safe. Users' responsibility ATEX 137 requires users to look at their work place as a whole. While manufacturers take responsibility for individual pieces of certified equipment, is up to the end user to ensure the work place is a safe environment. Since July 2003, any 'work equipment', new or old, must comply with the minimum requirements of the Worker Protection Directive (ATEX 137) and be safe. This safety cannot be assumed but, in the case of existing equipment, must be assessed and documented through risk assessment and proven evidence. This risk analysis should have been completed by 1 July 2003, but anecdotal evidence suggests that the user base has been slow to respond. This means that End users urgently need to review their equipment and provide an analysis as to whether their equipment can be a source of risk. It is quite possible that users are confusing this with the deadline applying to the 'work places' for drawing up the 'Explosion Protection Measures' (30 June 2006). This document needs to show how all the 'works equipment' operate together in the 'work place'. In particular, it needs to explain how the user intends to stay in control of the plant in an emergency situation. For instance, during a power supply failure, systems such as cooling and fire pumps need still to be working. But this exercise is separate from the risk analysis of individual pieces of equipment, which should be complete now. While the enforcement bodies may not yet have clamped down on every offending motor user, they are likely to become more demanding in the future, particularly in activities that can affect employees or members of the public. It is also worth remembering that responsibility under ATEX is personal. If the company has not even carried out its risk assessment, the apportioning of blame in the case of an accident will not take long to sort out. ABB is to become the first electric motor company in the UK to repair and rewind hazardous area motors to the ATEX Directive. Under ATEX 137, end users are personally responsible for the safety of motors in hazardous areas. But if the motor is approved to ATEX 95, the manufacturer is responsible for the safety of the motor, provided it is used correctly. ABB will now become the first electric motor company in the UK market to take the same responsibility for repaired and rewound motors as it does for new motors, ensuring that the motor remains approved to ATEX 95 even after a repair. The condition is that the motor is of an ATEX approved model, manufactured by ABB and repaired by its ABB Motor Service Partner network. ABB will audit its partners' workshops and train the personnel to ensure that the repair meets the same safety standards as the original work. ATEX approved repairs will initially be carried out at six workshops around the country, although customers will be able to access these services through any of the 15 members of the ABB Motor Service Partner network. The service will be rolled out during the spring of 2004. SERCOS-III combines real-time and Ethernet At the Hanover Fair in 2003, the so-called Interests Group SERCOS (IGS) announced a new project involving linking the existing high-performance SERCOS interface and the Ethernet standard to form a new generation of SERCOS, named SERCOS-III. Work has proceeded as scheduled so, as promised, a progress report was issued at the SPS/IPC/Drives 2003 show in NŸrnberg, Germany In the eighties, the German ZVEI and VDW organisations initiated a consortium to specify a digital open interface that would ease the transition from analogue to digital drive technology. Thus, the SERCOS interface was born. The first generation SERCOS interface supported transfer rates of 2 and 4 Mbit/s and was mainly used for advanced machine tool applications. In following years, the interface was widely accepted worldwide in many different industries, and in 1995 the SERCOS interface was approved as IEC standard 61491. The second generation followed in 1999. The transfer rate was increased to 8 and 16 Mbit/s and the service channel for the transfer of non-synchronous data was expanded. This technology has been available since 2001 in the SERCOS816 ASIC, with downward compatibility to the first generation. The collision-free data transmission based on a time slot mechanism, together with the highly efficient communications protocol of the SERCOS interface, ensures very high performance and the best possible determinism. Up to 40 axes can be synchronized with a cycle time of 1ms and a jitter less than 1µs.k. Superior performance With this performance, IGS sees the SERCOS interface clearly ahead of other standardised interfaces like Profibus or CAN and claims that not even the solutions are based on Fast-Ethernet with data rates of 100 Mbit/s show a better performance. For these reasons, it says, the SERCOS interface has become a de-facto standard in various industries, especially for multi-axis applications. The SERCOS interface was originally intended to be a drive interface, but now has become a universal motion control interface. The interface has revolutionised whole areas of machine building, the shaftless printing machine with its more than 100 axes synchronised via the SERCOS interface, packaging machines or multi-axis machine tools. Whilst most of the drive interfaces on the market are proprietary and can only be used with the manufacturer's own drive, more than 50 control manufacturers and 30 drive manufacturers offer SERCOS interface products and it has status as International Standard IEC/EN 61491 - any manufacturer can implement the SERCOS interface without having to pay license or membership fees. In SERCOS-III, the idea is explored of combining the proven mechanisms and properties of the SERCOS interface with the Ethernet, thus creating an advanced version of the most successful open motion control communication interface. SERCOS-III is based on the established real-time mechanisms of the original SERCOS interface and continues to work on the principle of cyclic data transfer with an exact time pattern. IGS maintains that a hardware-based synchronisation is the indispensable prerequisite for the reliable implementation of motion applications. SERCOS-III will have a ring structure like the current generation SERCOS interface. Conditional on the Ethernet physics, however, it is not a single, but a double ring structure (Fig. 1). This double ring structure offers the possibility of redundant data transfer. This is an enhancement to the second generation SERCOS. With SERCOS-III, in case of a break at any point in the ring, the communication continues. The plant works on while the integrated diagnostics tool signals the break, which can be repaired without interfering with the plants' performance. In addition to the ring structure, a linear structure is also possible. The linear structure doesn't offer the redundancy advantage, but it does save a wire connection. SERCOS-III does not use the star topology of the standard Ethernet. There are no hubs or switches needed. SERCOS-III has been defined such that any standard IP telegram (eg TCP/IP) can be transmitted in a non-real-time time slot, in parallel to the real-time transfer of the data required for motion control. The SERCOS-III controller is able to exchange these telegrams with superordinate devices in the network. Thus, SERCOS-III combines the established real-time mechanisms and diagnostic capabilities of the SERCOS interface with universal communication based on Ethernet (Fig 2) Direct communication between slaves is currently not possible with the SERCOS interface. However, this feature would be advantageous in some motion control applications. The Ethernet physics enable such a data transfer from slave to slave, and the new SERCOS-III will support this feature. The SERCOS interface has a service channel, which can be used for the transfer of communication data as well as parameter or diagnostic data. To keep SERCOS-III downward compatible, it too will have the service channel. An additional optional IP channel can be added, with which it is possible to transfer real time or non-real time data by standard Ethernet frames. The cyclic channel and the IP channel are configurable. SERCOS-III halves the minimum cyclic time of the current SERCOS interface from 62.5µs down to 31.25µs. Because of the greater bandwidth of the Ethernet physics, it is still possible to connect an adequate number of slaves, despite the short cycle time. Thus, it is possible to implement not only decentralised drive concepts but also concepts with centralised signal processing. With a decentralised drive concept, all control loops are closed in the drive. With centralised concepts, only the current loop is closed in the drive, whereas all other loops of several axes are implemented in the central control electronics. SERCOS-III is the only open motion control system that supports these structures. Modular concepts The trend towards modularisation requires motion control concepts that offer the possibility of synchronising several machine modules (Fig. 3). Some proprietary solutions, based on SERCOS interface physics, already exist. The aim of SERCOS-III is to standardise this type of communication. It is planned to define a profile for the synchronisation and communication between motion controls. Safety functions will be part of the future standard in motion controls and drives. Safe data transfer will be supported from the very beginning; safe and non-safe data will be transferred with the same mechanisms. SERCOS-III performance SERCOS-III will have a substantial increase in transmission speed. Some typical values are listed in Table 1. Figure 4 illustrates the types of communication needed by the automation industry, classified into four real time types. The figure shows the coverage provided by the ODVA, PNO and IGS solutions. The standard Ethernet communication is also included, if the IP channel is used without the cyclic real-time channel. When will SERCOS-III be available? The basic concept has been defined and approved by the SERCOS member organisations in Europe, North America and Japan. Detailed specifications are being developed by a technical working group, which includes various member companies. Since SERCOS-III is based on proven and tested profiles, work on the specifications will mainly concentrate on the hardware and additional features. First prototypes of the SERCOS-III hardware will be available in 2004, with first products envisioned for 2005. IGS USE FASTREPLY u126 ON THE WEBSITE ENTER u126 ON ENQUIRY CARD A validated laboratory facility A new £500,000 FDA-validated control and data acquisition system has been commissioned by AstraZeneca for its Large Scale Laboratory (LSL) facility in Macclesfield The LSL facility is a multi-purpose production unit, manufacturing kilo-scale quantities of primary pharmaceutical products for use in clinical trials. It consists of 18 independent production units, which include heat cool reactors, cryogenic reactors, a hydrogenator and chromatographic unit, plus support utilities. Engineers from Eurotherm, prime contractors Jacobs Engineering Group and AstraZeneca have developed a sophisticated DCS based on a number of Eurotherm Visual Supervisor controllers and EurothermSuite software. The system will monitor and control all local operations as well as provide management reports and other secure data. The control system architecture is based on 18 Visual Supervisors (Eurotherm T800) providing stand-alone unit control with local monitoring of individual laboratory reactors, tray dryers, etc., I/O is provided using Eurotherm 2500 System I/O controllers. This is supported by a central supervisory system featuring redundant EurothermSuite Operation Servers to provide management visualisation, long-term tamper proof logged data and audit trails. Distributed Operations Viewer nodes allow an overall view of the complete facility for management purposes. EurothermSuite Operations Viewer/ Server is a PC-based system designed to provide overall management and control of a complete process. It includes Invensys Wonderware's world leading software InTouch software and is designed to meet the diverse needs of operations, maintenance and plant management. The simple to use display structure provides data to users in a fast and meaningful way. Standard features include client/server architecture with master/backup servers, defined display structure, trending, sophisticated alarm functionality, single global database, and time synchronisation. Security issues 21CFR Part 11 related security issues in this system are handled by the Security Manager utility, which provides a central point for managing user accounts. With 18 Visual Supervisors and 5 PC nodes the routine ageing of passwords could create a significant management task. Each operator would have to update each unit, which would have raised the probability of numerous locked out passwords. Security Manager provides a central point for administrating users and password control, removing the barrier completely. Once users have updated their password within Security Manager the security information is deployed to the subscribed nodes. This package creates a tamperproof, audit trails file, which includes password access security. Visual Supervisor (Eurotherm T800) is a powerful multifunction controller with data logging and integrated display. It provides all the features required to control and monitor processes, functioning as either a stand-alone unit or as a building block within a larger system. Standard features include batch management to ISA-S88 with batch log, recipe and setpoint programmer, accurate continuous and sequential control, support for Modbus and Profibus, barcode reader and printer support, as well as time synchronisation. Visual Supervisor's Auditor feature supports Electronic Records and Electronic Signatures. Additionally on multiple Visual Supervisor node systems, the central control of all security functionality can be achieved with the Security Manager utility. The implementation is seen by Jacobs' Lead Control and Instrumentation Engineer Chris Southan as providing capabilities normally inherent within a considerably more expensive DCS and representing a much lower-risk option than PLC/SCADA architectures, where computer validation and 21CFR part 11 compliance were considered more difficult. Eurotherm USE FASTREPLY u131 ON THE WEBSITE ENTER u131 ON ENQUIRY CARD A wider world of industrial automation The recent acquisition of Interkama, the trade fair for process automation, completes a full line-up of automation displays at the next Hannover Fair (19-24 April 2004) the new combination of Intermaka+ and the 'home-grown' trade show Factory Automation, which focuses on automated systems for the production of goods, means that for the first time the complete spectrum of industrial automation will be featured simultaneously. The launch of this concept, setting the stage for this horizontally-integrated flagship industrial automation fair, was initially set for 2005 but now has the green light for 2004. The line-up also includes Digital Factory, a new platform for software and IT applications in industrial firms, as well as the international flagship trade shows Energy, Subcontracting, SurfaceTechnology plus Powder Coating Europe, MicroTechnology and Research & Technology. For Sepp D Heckmann, Director of organiser Deutsche Messe, robotics is a good example of the benefits that this integral concept brings: "Overseas visitors don't come all this way just to see robotics. They want to see the complete automation picture, how all the different parts fit together - that's the real added value for them. By opposing the fragmentation of individual trade fairs with its potentially negative impact on entire industries, two of the top international trade fair companies have chosen to act responsibly for the benefit of the economy at large. We are also convinced that our joint initiative has made a major contribution to bolstering Germany's status as a prime location for trade fairs." Highly regarded According to a recently published survey carried out by the independent Hamburg-based Consumer Research Association (GfK), the Hannover Fair is highly regarded by decision-makers in Germany and all over the world, and is seen as the international platform for presenting the complete spectrum of interdependent technologies and applications that make up industrial automation. For some 80% of those taking part in the study from Germany, France, the United Kingdom, Spain and Italy, Factory Automation is the Number One international trade show in its field. Given the present depressed state of the economy, which is also a real challenge for the exhibition business, this is very good news indeed, and it has encouraged Deutsche Messe AG in its plans to press ahead with the new horizontal display concept in 2004, when the complete spectrum of industrial automation technologies will be presented under one roof. The range of exhibits at Interkama+ covers the whole spectrum of process automation: automation and IT solutions, field devices and components, control and regulatory systems, plus engineering, maintenance and services. The visitor potential for Interkama+ alone is estimated at around 40,000 industry professionals from all over the world, representing 16 different industries that use process automation. Principal among these are the chemical industry, the pharmaceutical industry and the petrochemical industry. An equally promising opportunity exists in the form of the worldwide Interkama joint ventures agreed upon. A cornerstone in this agreement is the cooperation between Deutsche Messe AG and Messe DŸsseldorf on all Interkama fairs throughout the world. The presence in these markets will span not only the field of process automation but also production automation. Interkama China, which enjoyed a highly successful launch in Shanghai, will thus continue to be organised as a joint project in future. Other exciting opportunities on the horizon take the form of further events planned in Russia and the Czech Republic where Messe DŸsseldorf, thanks to its strong position as Deutsche Messe AG's partner, will open up a share of the market. The same applies to India. The Hanover Fair in turn has a strong base in Turkey, which will help Messe DŸsseldorf establish a foothold there. Further venues are under consideration but have not yet been finalised.
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