CE Marking of Plant and Machinery, The Basics

According to the Machinery Directive, a machine manufacturer is anyone who assembles machines or machine parts of various origins and places them on the market. A manufacturer may be the actual machine builder or – where a machine is modified – the operator. In the case of assembled machinery, it may be the manufacturer, an assembler, the project manager, an engineering company or the operator himself, who assembles a new installation from various machines, so that the different machine parts constitute a new machine.

However, according to the Machinery Directive, only one manufacturer is responsible for the design and manufacture of the machine. This manufacturer or his authorized representative takes responsibility for implementing the administrative procedures for the entire plant. The manufacturer may appoint an authorized representative, who must be established in the EU, to assume responsibility for the necessary procedures for placing the product on the market:

• Compiling the plant’s technical documentation
• Complying with the technical annex
• Providing operating instructions for the plant
• Affixing the CE mark in a suitable position on the plant and drawing up a declaration of conformity for the entire plant

Using Resources Carefully: Comprehensive environmental protection at Pilz

Whether we are talking about energy engineering, hazardous substances or instrument engineering: at Pilz, looking after the environment is a core part of the corporate philosophy. With the solar-powered building climate control system taken into operation last autumn, the company now also has sustainable ways to use energy.

At Pilz, sparing use of natural resources starts in the Central Purchasing department. Here, right at the start of the logistics chain, the company lays the foundations for active environmental protection. Purchasing guidelines designed to comply with the environmental requirements laid out in REACH (the future European Community Regulation on chemicals and their safe use) and RoHS (European Restriction of Hazardous Substances Directive) and evaluation of suppliers also on the basis of their environmental performance ensure that components and parts satisfy the relevant environmental standards.

Concern for the environment is also very much to the fore in the development of products. Already during development, issues are addressed such as whether a product can be designed more compactly so that, ultimately, energy and materials can be saved.

It is easy to think that this should be a simple matter, but once components start to get very compact they must not consume large amounts of energy. Otherwise they would get too hot. The PNOZsigma, for example, has been designed according to these criteria. The relay only uses increased amounts of energy during start-up, but during operation the energy saving circuitry comes into play. This ensures that overheating is impossible, and the desired energy saving effect is achieved.

Environmentally friendly manufacturing

Designing products to be environmentally friendly is just one side of the coin. The other is to manufacture them in a way which is environmentally sound. At Pilz, the implementation of environmentally aware production guidelines starts in the Production Engineering area: auxiliary materials are carefully selected according to their environmental compatibility. The use of unleaded solder for example is implemented on a voluntary basis in accordance with the RoHS guidelines. The alcohol-free, water-based flux materials for cleaning the circuit boards also contribute to this. In terms of environmental protection, this also means that fewer hazardous substances are stored in the company. Overflow troughs safeguard this storage so that potential risk of ground contamination is eliminated from the start.

Production itself is designed to be environmentally friendly, with sparing use of resources. For example, waste heat is used to operate the ventilation and air conditioning system. With the aid of heat exchangers, large amounts of energy can be saved in this case.

CO2 under control

Pilz is doing a number of things to reduce the company's carbon footprint: focusing lighting is one way to reduce CO2 emissions – without compromising the minimum brightness requirements stipulated for the workplace. Presence monitors ensure that the light is only switched on when it is actually needed. However, the biggest savings in terms of CO2 emissions have been made with the climate control technology which was taken into operation in 2008 and features state-of-the art engineering. The entire Peter Pilz Technology Centre is both heated and cooled via a solar heat plant. Energy efficiency has been significantly improved with the new system. Another measure is the gas heating which has been optimized with a new condensing boiler, which is now capable of heating two buildings at the same time.

Protecting the environment means taking responsibility

Today, every company also has a responsibility to other people and to the environment. Pilz understands this responsibility. This is why Pilz employees are sensitized for environmental concerns with the aid of various media, including for example the Intranet and special training sessions. This is because efficient environmental protection measures must be comprehensive.

What is a Machine?

For the purpose of the Machinery Directive, a machine is:

• "An assembly of linked parts or components, at least one of which moves, and which are joined together for a specific application.”

The following are also considered machines for the purposes of the Machinery Directive:

• "An assembly of machines or complex plants (complex plants include production lines and special purpose machinery made up of several machines"
• "Safety components, such as light curtains, safety mats, etc."
• "Interchangeable equipment that can modify the basic functions of a machine."

Click here for more information about the Pilz Safety Compendium and the Machinery Directive.

An introduction to CE Marking.

The CE mark stands for "Communauté Européenne". A manufacturer uses this mark to document the fact that he has considered all the European internal market directives that are relevant to his product and applied all the appropriate conformity assessment procedures. Products that carry the CE mark may be imported and sold without considering national regulations. That’s why the CE mark is also referred to as the "Passport to Europe". Generally speaking, all directives in accordance with the new concept ("new approach") provide for CE marking. Where a product falls under the scope of several directives which provide for CE marking, the marking indicates that the product is assumed to conform to the provisions of all these directives.

A Brief Note About EU Standards

On their own, standards have no direct legal relevance until they are published in the Official Journal of the EU or are referenced in domestic laws and provisions. These are the publications by which a standard can acquire "presumption of conformity". Presumption of conformity means that a manufacturer can assume he has met the requirements of the corresponding directive provided he has complied with the specifications in the standard. So presumption of conformity confirms proper conduct. In a formal, legal context this is called a reversal of the burden of proof. Where the manufacturer applies a harmonized standard, if there is any doubt, misconduct will ned to be proven. Where the manufacturer has not applied a harmonized standard, he will need to prove that he has acted in compliance with the directives.

If a manufacturer does not comply with a standard, it does not necessarily mean that he has acted incorrectly. Particularly in innovative industries, relevant standards either may not exist or may be inadequate. The manufacturer must then demonstrate independently that he has taken the necessary care to comply with the safety objectives of the relevant directives. Such a route is usually more complex, but, in an innovative industry, it is often unavoidable.

It's important to stress that the EU does not publish every standard in the Official Journal, so many are still not harmonized. Even if such a standard is deemed to have considerable technical relevance, it will still not have presumption of conformity. However, sometimes a standard that has not been listed in the EU Official Journal does achieve a status that's comparable with harmonization. This is the case, for example, when a standard that's already been harmonized refers to the relevant standard. The standard that is not listed in the EU Official Journal is then essentially grandfathered into harmonization.

Pilz CE Marks Machines for Saint-Gobain Performance Plastics

Pilz Automation Safety L.P. provides technical consulting services such as CE Marking, engineering, risk assessment and training, in addition to producing automation and safety products. Saint-Gobain Performance Plastics chose to utilize Pilz’s experience and expertise in the CE marking of several pieces of equipment including, Sani-Tech Fusion Welder, SaniPro Flange Former and SaniSeal Label Molder.  This equipment is used to work with and install performance plastic products. For instance, the Flange Former is used to thermally form a flange on the end of a plastic pipe, the label molder is used to seal a label and a color code panel onto a pipe section and the welder joins sections of pipe. All of these tasks are critical to Saint-Gobain’s customer base to properly use and install its products. Pilz Automation Safety L.P. identified the various CE Marking directives that apply to each of the machines and selected the standards associated with the relevant directives to ensure conformance as required by law for CE certification.

The process of CE marking, as required by EU law, is designed to ensure that a product has met consumer safety, health and environmental requirements. By bringing Pilz in as consultants Saint-Gobain was able to leverage Pilz’s expertise and experience in CE marking, shortening the time the overall process took while allowing their specialized staff to continue to focus on core competencies. The out-sourcing process also allowed them to bring in highly skilled and competent engineering teams to conduct governmentally required work while still maintaining their own high level of customer satisfaction and support.

Ambassador for Safe Automation

“Every company needs a hierarchy. But what a company doesn’t need is hierarchical thinking”, stresses Renate Pilz, Managing Partner of the Pilz group. “That has always been my creed. And that’s how we do things here.”

Walking round the company with Renate Pilz it is obvious: her staff respect her and hold her in high regard, and vice versa: even when time is short she is prepared to listen, even to her employees’ personal problems.
That she is not only a respected but also a successful businesswoman is something that’s repeated time and time again within the industry; and it’s a fact that is supported by the company’s figures.

After her husband lost his life in a plane crash in 1975 and managers were appointed to run the company in the interim, Renate Pilz took over the management of the company in 1994. The company grew, but she recognized the potential that was not being used.

She developed Pilz from a national supplier into a company operating internationally, with 23 overseas subsidiaries in countries including USA, China and Brazil.

Pilz has been implementing the Takeda process optimization strategy. Although the company’s operations were already based on a CIP strategy (continuous improvement process), existing procedures had to be made more efficient to make the company fit for global competition. “The Takeda concept was brought to our attention by one of our very good customers, who had achieved significant improvements with it”, explains Renate Pilz.

The strategy, which Hiroshi Takeda calls “The synchronous production system” and which Pilz calls PPS, is relatively unknown. PPS stands for Pilz Production System; its aim is to involve all employees in the identification of potential improvements within the group and their subsequent implementation, and to promote customer-oriented thinking. Renate Pilz established a separate team for its implementation; the team reports directly to management and its members have in part been released from other work.

The Takeda philosophy is based on the CIP approach (continuous improvement process), but employees are much more closely involved – one reason why Renate Pilz immediately approved of the approach: “We are always searching for appropriate instruments. The concept seemed to be very good because it is a very in-depth system, which integrates people.”

Continuous process optimization is achieved through regular workshops. “The workshops stimulate the creativity of our staff”, the managing director has recognized, “and also strongly encourage interdepartmental working.”

The key difference from CIP lies in the immediate implementation of the results. “Immediate and consistent implementation”, summarizes Renate Pilz. “There are many optimization strategies where a great deal of effort goes into working something out – and then it is postponed until a suitable date can be found for its implementation”.

With PPS there is an understanding of the issue within the team, the working group is composed accordingly and deals with the issue, implementing the conclusions during the actual workshop. The groups are designed to be interdepartmental. “It is often the interfaces that are problematic, and this way they open up – purely through this type of co-operation”, says Renate Pilz. “The result is genuine co-operation, all staff members can have a say in these groups.”

The selection of workshop members depends on who is affected by the issue and whether they can contribute towards solving the problem. One example is the standardization of procedures. “With standardized procedures you can achieve better quality and greater flexibility” explains Renate Pilz. “So you can react more flexibly with the existing team, housekeeping is more readily understood – why the process must run in this way and no other.” Increased efficiency and easier work processes for staff are the result. “For example, if the workplace is made more ergonomic at the suggestion of a female staff member, thus making access to parts considerably easier, that lady’s work becomes more agreeable and she has been part of the process”, says the managing director, quoting a real example. “But first of all you need to become aware of the matter. For years she had fetched the parts from a box on the floor: nobody had the idea to simply place the box higher up – it had always been done like that.” The fact that it is her own design helps the measure to become accepted and increases efficiency and motivation, as well as improving quality.“When problems that have been recognized are resolved very quickly, then it is worth supporting such process improvements”, is the experience of Renate Pilz. “And when implementation is consistent and fast, the concept also establishes itself quickly. This doesn’t just encourage interdepartmental working, it makes it an absolute condition.”

One visible sign of this: the foreman’s office has gone. It has been turned into a team room for production, production technology, development, purchasing and the various fields. The group meets in the team room and deals with the issues there. There were no problems when the foreman’s office was removed. “The staff sees that it’s just part of the job. If there is any resistance, it is generally down to anxiety. And as executives, it is our job to ease such anxiety”, says Renate Pilz, demonstrating her approach to leadership.

The PPS strategy runs through all areas of the business. “Our aims are to substantially increase efficiency and delivery reliability, to optimize and standardize work processes and work equipment, to reduce pressure in the workplace and thereby improve quality”, says Renate Pilz. “Ultimately we are doing this to safeguard the site of course”.

She does not wish to comment on other companies abandoning their sites, but her opinion is reflected in her description of the Pilz strategy: “We don’t complain about the things we can’t do, but we do whatever is within the realms of possibility. And we do that by communicating openly with each other, internally and externally.”

That’s why customers and supplies are also included in the strategy: the former in particular set the tempo for production. “The better the information from the customer, the better we can be too”, says Renate Pilz.

Son Thomas Pilz manages the subsidiary in the USA and daughter Sabine Kunschert works as a manager in Ostfildern. “And so the foundations have been laid for a seamless transfer to the next generation”, says Renate Pilz, “and I am grateful that it all worked out so well.”

Not that she’s thinking of ending her business career just yet. She enjoys the job too much for that, despite the 60-hour week: “I get so much pleasure out of working with our staff and I have a lot of respect for what they do.”

Author:
Hajo Stotz
The Manufacturer

Glastechnik Holger Kramp GmbH- Water Treatment Plant Solution

Glastechnik Holger Kramp GmbH based out of Stockelsdorf, Germany needed to improve the operational and environmental safety of its water treatment facility where waste water from grinding, drilling and similar machining functions is cleaned and made available again to the production process. The plant consists of several large storage tanks and containers and operate in close contact with the production facility via incoming and outgoing water pipes and pumps. The process of design started with a systematic analysis by Glastechnik Holger Kramp along with Pilz application engineers, to determine what requirements would be needed to improve the safety and reliability for both the human operators and to prevent possible environmental contamination. It was decided that two major goals had to be accomplished, develop a user-friendly and service-friendly diagnostic system, that would, in the event of a fault provide the location and cause of the fault and tips for repairing/remodeling the fault. The goal of this system was to reduce the downtime created by maintenance and safety situations. The safety aspect of the system was accomplished using a series of Pilz E-STOP pushbuttons and coded PSENcode safety switches, in conjunction with the multifunctional safety system PNOZmulti. The PNOZmulti modular safety system watches over the emergency stop devices operating both locally and across the range of machines, as well as the link between the machines and the water treatment system: A fault around one individual machine does not immediately mean that the whole plant has to be brought to a standstill. However, if the central water treatment system should fail, this must result in a controlled overall shutdown of the plant. The safety system also detects potential shorts between contacts, monitors the speed of the pump motors and guarantees that they shut down in the case of a fault. The implementation of this centralized and integrated safety and diagnostic system guarantees that user-friendly solutions are found quickly and accurately. The use of clear easy to understand event and fault messages also make the system significantly easier and faster to diagnose and repair.

Pilz is the missing link in Link Engineering's machine safety

Link Engineering is a multinational company based out of Plymouth, Michigan that designs and provides precision test equipment to a variety of industries. Primarily focusing on the needs of the automotive industry and its part manufacturers, Link provides test equipment and a variety of testing services. Link needed to upgrade and centralize the machine guarding and safety monitoring of their automotive dynamometers, lacing machines, friction machines and more. The Pilz line of PNOZ safety relays and PSEN sensors was chosen to complete the project. They decided to use the PNOZ S4 base unit and the S7 Sigma contact expansion module to monitor safety related functions. The PSENmag is used to monitor entry into gated areas of the machinery and production equipment and monitors the position of movable guards in accordance with EN 60947-5-3. It is approved for safe applications up to, Category 4 of EN 954-1, PL e of prEN ISO 13849-1 and SIL 3 of EN IEC 62061. Because the systems are monitored through a centralized safety network, Link increased safety standards they meet while keeping their safety footprint small and operation costs low. In the dynamometer operations, Link used Pilz’s PSENmag and PSENmech switches. The PSENmag is a non-contact, magnetic safety switch used to monitor the position of movable guards. The PSENmech ensures that the safety gate is interlocked (guard locking) until the hazardous process is complete. This allows Link to reduce the safety footprint as with their other machines, but it also gives them a greater degree of flexibility to setup dynamometer configurations. Link chose Pilz due to their proven track record of high quality products and support and the flexibility, easy setup and expandability Pilz products offer and because Pilz North America L.P. is a local company response times will be quick if technical problems arise.




LINK ENGINEERING COMPANY has been in operation since 1935 with offices around the globe. LINK designs, develops, manufactures, installs, and operates a wide array of test systems for the automotive, truck, railroad, and aerospace industries. They have provided test systems for brakes, transmissions, clutches, axles, driveline components, steering systems, springs, tires, wheels, and a variety of other components. LINK also provides testing services to a global customer base. For more information visit http://www.linkeng.com/.

Pilz offers a full range of leading-edge safe automation products and services. Products include sensor technology, electrical monitoring relays, and automation solutions with motion control, safety relays, programmable safety and control systems and an operating and monitoring range. Wireless and safe bus systems are also available for industrial networking.
Pilz also provides a comprehensive range of consulting, engineering and OSHA-approved training services. Pilz performs facility safety reviews for due diligence relating to mergers and acquisitions. For more information visit http://www.pilz.us/.

Nuclear scientists choose PSS programmable safety

No other Australian safety system faces the intense scrutiny focused on the country's nuclear reactor... ...and, arguably, no Australian workplace takes safety more seriously. So, when some of the world's most brilliant scientists use a new Australian Nuclear Science and Technology Organization (ANSTO) experimental facility, they will be protected from radiation exposure by a meticulously designed network of Pilz Programmable Safety Systems (PSS). The new AUD$350million OPAL reactor is soon to produce neutrons for eight neutron beam instruments (NBIs) that will allow scientists to investigate the atomic structure of new materials, chemical reaction kinetics and biological processes. The instruments will operate almost continuously; research breakthroughs are expected from the AUD$30million Neutron Beam Instrument Project (NBIP) and the international scientific community is already enthusiastic to gain access to the information. Managing both Australia's most stringent safety standards, together with the need for maximum uptime, called for a sophisticated safety approach. ANSTO electrical project engineer Frank Darmann and his team were responsible for the solution. The safety system begins with the science itself, which is deceptively simple at face value. Neutrons from the reactor are directed at the materials under investigation to see how they scatter, thereby revealing the materials' atomic structures. Three shutters control the flow of particles along the neutron beam guide. A primary shutter sits at the reactor face and a secondary shutter at the guide hall interface, which is closed when access to the shielded areas is needed. A third, sample, shutter is attached to each instrument. Access to the instrument area is interlocked with the sample and secondary shutters, using Fortress gate locks. The positions of another 76 moveable radiation-shielding blocks are detected by dual-channel limit switches. An array of light curtains, sirens, dual-channel safety switches and 78 emergency stop switches adds to the security of the NBIP. It all adds up to a highly complex system, with some 1200 inputs and outputs (I/O). Coordinating the I/O are five Pilz PSS programmable safety systems (or safety PLCs), each one dedicated to a separate safety zone. This impressive configuration is easily justified, says Dr. Darmann, who ran the numbers to compare the operational and safety performance of traditional electro-mechanical systems with the PSS. "The mean time between failures (MTBF) to a safe condition - that is, a failure that only affects operations, not safety - of this myriad of devices with a Pilz PSS overseeing them would be 3.4 years," he says. "Otherwise, we would have needed a complex web of interconnections and the MTBF to a safe condition would have been less than six months." "The safety numbers were even more compelling. The MTBF to a potentially unsafe mode for an electro-mechanical system was calculated to be 5.7 years compared to 140,000 years for the Pilz safety PLC. The Pilz PSS safety PLC concept was a clear winner." The superior reliability of the Pilz PSS was also matched with powerful diagnostic software, so that even if a failure did occur, downtime would be minimized. "Locating a fault in a maze of 100 relays would be difficult and time-consuming but the PSS indicates the malfunctioning unit or circuit exactly on a touch screen," Dr. Darmann says. "Circuitry is automatically and continually checked for welded contacts and short circuits instead of once a year or never." Dr. Darmann identified a host of other benefits too, including the ability of the logic-based system to be readily expanded, reconfigured and upgraded. "You basically need much less control cabinet real estate - about 70 per cent less in this case. The web of complex physical wiring interconnections is also eliminated, which makes tweaking the system to match changing and demanding operational requirements much easier, and also simplifies fault finding, documentation, and change management processes. A legacy system is avoided. New operating rules can be programmed in a straight forward manner in software that is not possible using hard-wired relays." The Safety Interlock System (SIS) and Instrument Control System (ICS) remain separate for maximum safety. Dr. Darmann says: "Each has independent logic elements, power supplies and cabling. Opto-isolation of logic between the two systems ensures electrical separation. There are, however, some interfaces between them to assist the smooth operation of the instrument. For example, the ICS has access to all of the logic states that exist within the NBI SIS so that computer control of the instrument does not commence until the SIS deems it is safe. In addition, the ICS can make a limited number of requests of the NBI SIS, such as closing or opening a shutter after the furnace temperature is met, which it is free to deny." ANSTO's preference for specialized safety carried through to its choice of safety system, which was supplied by Pilz Safe Automation's John Skinner. Dr. Darmann comments: "Pilz was chosen as the main vendor for safety logic processing hardware over others because of their long experience in the field, participation in the Australian Standards 4024.1 review committee and the significant back-up and resources of the German headquarters. I found the staff to be knowledgeable of the safety standards and they could give advice on choices and approaches. Other companies had safety PLC capabilities too but were principally involved with general automation; we wanted a specialist who intimately knew the intricacies of safe automation." The safety interlock system was installed by ANSTO electrical technicians, Dan Bartlett and Geoff Scott, guided by circuit schematics drawn by Barrie Lewis. Code was programmed by Dino Ius, while human machine interfaces were drafted by John Oliver and installed by Anthony Kafes. The system is documented in design and commissioning manuals written by Dr. Darmann. As a result, the safety system complies with Australian Standards AS4024.1, the NHMRC code of practice stipulated by the regulator, ARPANSA, and state regulations, yet it performs unobtrusively. "The instruments are used by visiting scientists from overseas who might only stay a day or a few days," Dr. Darmann says. "They are interested in using the instrument for science, so the safety interlock system and the human interface must be instinctive. It also has to survive interaction with a novice user without falling over and requiring technical maintenance." "At similar institutions in the past, electronic safety measures were achieved with a simple chain or barricade. In fact, one scientist told me during a review of the design that 'we used to do this safety interlocking with a $5 box of transistors'. Despite this history, there was no hesitation on the part of the scientists or the review group to approve the design or funds required. This safety system is benchmarked to be the world's best but we believe any safety interlocking system should be designed along the same principles of safety, compliance and performance."

 
For more information on the products mentioned in this article please email marketing@pilzusa.com


 
For more information on Pilz Services please email

consulting@pilzusa.com

SafetyEYE® Monitors KUKA’s RoboTeam

KUKA RoboTeam in a jigless cell

A team of robots comprising two process robots and two handling robots welded the car door together in one work stage. Two jigless grippers combined to perform the geometric functions. The two gripper half shells were positioned by cooperating robots. The jigless bodyshop, therefore, is an innovative plant technology, which implements the very latest robot functionalities without the classic holding and clamping technology. The cycle time can be minimized through direct "geometric coupling". Autonomous control systems provide a high degree of flexibility. Cooperation between the team robots allows for highly flexible component positioning.

SafetyEYE® protects workers in the infeed areas
These days robots almost always work behind safety fences, screened from the application operator. New safety concepts such as SafetyEYE® help to do away with the fences and barriers that come between worker and robot. From above, SafetyEYE® simultaneously protects workers in both infeed areas independently. The operator enters the transfer area, where he is detected visually. This is safely recorded and the data is transmitted to the safety-related robot control system. The aim is to avoid a collision; this can be guaranteed by the robot's reduced traverse speed, based on the distance from the operator. As a result, the operator can insert the component directly into the robot's gripper. At the same time, the operator has free access and a clear view of the process.

 Safety and Economy in Harmony
The robot's drives are safely deactivated while the component is inserted. If the worker leaves the infeed area's danger zone, the robot will slowly start to operate. As soon as the worker has left the warning zone, production will run at full speed. A safe stop in the infeed area / running the robot down safely while the workers are still in the infeed area saves on cycle times. As well as safeguarding the infeed area, safe robots also guarantee personal safety within the jigless cell through the software. As the robots can now move about close to the safety fence, the production area can be reduced, allowing for a compact body plant.

KUKA Robotics is the North American subsidiary of KUKA Roboter GmbH, one of the world´s largest robot manufacturers. Since building its first industrial robot in 1977, KUKA has earned an international reputation for robotic excellence. Virtually all of the 80,000 robots installed in the field use our PC-based controller, making KUKA the number one PC-controlled robot manufacturer in the world. KUKA offers a complete range of advanced design robots, covering all common payload categories, from 3 kg to 1,000 kg. Within this range you can always get the exact robot you need for your particular solution. Our PC-based controllers are easily expandable and offer cutting-edge technologies such as remote diagnostics, Windows interface, icon editor, fieldbuses, SoftPLC, OPC server.

Pilz and Komet: Modern Safety and Control Concept Leads to Greater Packaging Productivity

Faster, more flexible, safer – with this objective in mind, the level of automation on plant and machinery continues to advance in all industries. Both safety and control technology take these high requirements into account. If necessary, powerful components can be combined to form complete systems, which guarantee safety on the one hand, and can increase productivity on the other. If the user can adapt technology to suit his requirements, then he has a cost-effective, tailor-made solution. In many industries, packing is still associated with manual work. Where man and machine work together, the risk of injury must be minimized to the greatest possible extent. Safety devices used to be viewed as obstructive and inconvenient, but today the
opposite is true: modern safety and control concepts make handling easier, and plant and machinery more productive.

Faster thanks to the new safety concept
The semi-automatic vacuum-packing machine feeds in the bottom foil via a roller; it is then transported via a chain drive. The foil is brought up to temperature in the forming chamber; a special compressed air/forming procedure and the appropriate tool are used to create the desired tray shape for each packaged product. Staff use both hands to insert grilled sausages into the tray-shaped plastic film, six pieces per row and per pack, before the conveyor moves on and another set emerges from the forming station. After the filling station comes the sealing station: The top film seal is fed through a second roller; a vacuum pump extracts the air and thereby the oxygen. This slows down the activity of the micro- organisms, while the inflow of nitrogen prevents the sausage slices from sticking together. Finally, the top and bottom film layers are impulse sealed under pressure in the sealing chamber. The product packaging is now secure and durable. At the machine outfeed, longitudinal and transverse cutters separate the packaged product into individual trays, which are then fed into transport crates via conveyor. Two coils wind up the residual film cut from both sides. Sprinter is the name of the latest development from Komet, manufacturer of semi and fully automatic vacuum packaging machines. The company is based in Plochingen,Germany, and has its roots in the butchers' trade. It's in this field in particular that Komet's table-top units are used, as they provide an airtight seal for everything that needs to be kept fresh and preserved. Even in the butchers' industry there appears to be an irresistible trend away from the skilled producer and towards industrial production; customers increasingly ask for ready- packed goods, so Komet is increasingly focusing on semi and fully automatic machinery. Flexible and quick to convert, they can pack items in up to eight parallel trays, depending on the packaged product and the size, with or without automatic infeed. Even non-food goods can be packaged and sealed efficiently using  automated packaging machines.
Another reason why the machine is called Sprint is because, in comparison to the previous model Quickvac 2000, it can convey products to their packaging more quickly, using a less complicated procedure. That's because of a modern safety and control concept, which Pilz developed for Komet. Designed for maximum compatibility: sensor technology, evaluation device and visualization o n the Sprinter, the multifunctional safety system PNOZmulti configures simpler, safer interaction between man and machine. The safety system has a modular structure and can be used flexibly to suit the application. Instead of wiring, the user configures the needed functions simply, in a configuration tool. This saves time, space and money because there is no longer any complex individual wiring and all the safety related functions are located in one housing. PNOZmulti is cost effective when monitoring four or more safety functions and can also undertake standard control tasks. By comparison the safety devices on its predecessor were simplistic and mainly based on individually wired switches and contactors. Large covers safeguarded wide-ranging potential danger zones such as the forming and sealing stations via switch contacts. The infeed area in between was narrow and only allowed a one-up arrangement.
On the Sprinter, the cover on the forming station is reduced to a minimum. Instead, an advance security slide ensures that it is impossible to reach into either the forming or the sealing station from the filling station. If the slide switch is not closed, the safety system will prevent the bottom film from being formed and stop pressing and heat-sealing in the sealing station. Propulsion drives and valves are switched off; the central PMI operator
terminal (Pilz Machine Interface) receives an error message, stating the cause and the source. Magnetic safety switches, PSENmag, monitor the mobile protective hood over the sealing station, the longitudinal and  transverse cutters, and the lower positions of the lift cylinder plus the security slide on the forming/sealing station. The PNOZmulti also monitors the E-STOP and the enablers that control the heaters and valves (pneumatic + hydraulic). The risk of injury from the packaging machine, therefore, is kept to a minimum, both during operation and in setup mode. "With PNOZmulti the machine has a flexible safety concept which is really easy to adapt to our requirements. Now the infeed area has a three-up arrangement, so assembly is quicker and easier, plus the machine is more productive", says Harald Janke, Technical Manager at Komet.

Solution for safety and standard
A modern control solution also fell within the scope of the cooperation between Komet and Pilz. The standard control technology on the Sprinter also comes in useful for automatic operation and setup mode. "People at Komet were unhappy with the existing control solution and were looking for an efficient alternative", recalls Ralf Kessler, Applications Engineer at Pilz. Now they are using a PMI operator terminal in conjunction with a Profibus Master. A soft PLC runs under the Windows CE operating system. The standard I/O modules are logged and controlled via the PSSuniversal. The Pilz centralized control platform covers the whole I/O periphery as one system and is universally applicable. Users have three options: pure safety applications, combined safety and standard applications or exclusively conventional/standard control  functions.
With the grey, standard head modules it is possible to use analog and digital standard inputs and outputs on the fieldbus systems, without a functional connection to the safety technology. On the Sprinter, the head module of the PSSuniversal is also connected to the PMI via Profibus-DP, just like the PNOZmulti. Due to the system's modular design, the PSSuniversal can be individually adapted specifically to meet the respective requirement. If any adaptations are required, modules can simply be expanded or exchanged.

Benefitting from expertise
Pilz was also contracted to complete the electrical design, prepare the circuit diagrams and carry out the programming, including commissioning. "As a small company with around 30 staff we are reliant on competent, reliable partners for our electrical design and programming; we need partners who know what's happening and know what's important to us", says Janke, "Here we found Pilz to be a suitable partner, their technical advice was superb and the collaboration with the Pilz staff ran smoothly." The competence of Komet in terms of automation technology, combined with Pilz's expertise in matters of control technology and safety, jointly produced a new vacuum packing machine that operates more productively and is therefore of greater value.
Pilz is a global company, as such, not all standards and information will be applicable worldwide. Please check with your local Pilz office to ensure your factory and/or machines meet local standards.