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