Catalogue with selected Topics. Automation Electrical machines Power Electronics

Transcription

1 EN ISO 9001:2000 Certified Company innovative future oriented high-performance Education is the future Catalogue with selected Topics Automation Electrical machines Power Electronics

2 Company profile Address: ELWE Technik GmbH Elwestraße 6, Cremlingen, Schandelah Services: Development, production and distribution of technical training systems, training appliances and specialist technical furnishing for basic and advanced training in industry and colleges for further education. Business sales area: world-wide Legal form:: Limited company, registered at the Commercial Registry (HR) in Braunschweig under B 9806, UST-ID DE The company ELWE Technik GmbH is located in the near vicinity to the city of Braunschweig which lies in a geographically central position in Germany. We have direct access to the inter-european motorway and railway routes as well as to the main international airports of Frankfurt, Hanover, Hamburg and Berlin. Our company is located at the centre of a vigorously active technological region, the so called "Industrial Triangle" - Braunschweig, Wolfsburg and Salzgitter - where future-oriented hi-tech research and development is being undertaken in solar, information, gene, bio, steel and automotive technologies. ELWE Technik GmbH ELWE Straße Cremlingen OT Schandelah In this region, we currently maintain even by present day standards, an "untypically" high in-house production depth by manufacturing our products to the highest possible levels of quality. Several departments, which are equipped with the most modern CNC and laser machines for production work in the metals and plastics areas, combined with our high quality controls under the guide rules of ISO 9001, guarantee a first-class grade of quality continuity, control and durabilty in our products. ELWE Technik GmbH ELWE Straße Cremlingen OT Schandelah The in-house development of the products, together in a close cooperation with the regional "natural resources" of professors, lecturers and expert consultants, enables us to quickly and efficiently realise our products in a qualitatively, methodically and technically mature manner. Parallel to this, we can offer services in the areas of consultancy, project planning, tendering, training instruction, customer services and maintainance/repair. Our field representatives and agents willl attend to you on-site during every phase of the contract and remain your contact person after project clearance. As an extension to our services we can offer you comprehensive literature, seminars with qualified personnel and product instruction at either the customers locality or here at our factory. 2

3 Content...Page Didactical concept Automation: A quick word to our world of automation PLC-Trainer I for beginners...8 Performance characteristics (SPS starter trainer I - III) PLC-Trainer I - III...9 LOGO!-Trainer...10 S7 300 Trainer - Training systems for automation technology with original SIEMENS components ASIMA...12 ASIMA II...13 Linear drive...14 Mechatronic Compact System MCS...15 Process and field communication (SPS AS interface / Profibus DP with MCS models) Electrical machines: Servo drive and brake system (Embedded PC-Version)...17 Servo drive and brake system...18 Electrical Structure of Machines...19 Electrical machines in general...20 Three-phase AC Basic Circuits and Transformers...21 DC Machines...21 AC Machines...22 Three-phase Machines...23 Protective circuits for Electrical Machines / Control of Electrical Machines Fault Simulator for Contactor Circuits Automatic compensation of Reactive Power Comprehensive view of the available machines and furnishings Power Electronics: Power Electronics with ELWE Base grid system...29 Power Electronics with ELWE Experimental Module System CTT - case...31 Mains Rectifiers...32 DC Chopper...33 Pulse-Width Modulation...34 Switching power supplies...35 Frequency converter...36 Drive Technology (AC/DC)...37 Training Station / Laboratory furnishings...38 General terms of business...39 Fax enquiry

4 Educational concept -- We make technology easy to understand with: Experimental Panel Systems Experimental Modular Systems Experimental Plug-in Systems Experimental panels, with easy to read switching position symbols, circuit diagrams and result effect diagramms for each current experiment are mounted in a straightforward manner into the experimental frames. These offer outstanding communicative possibilties for theoretical, teacheroriented lecturing and presentation work. The experimental modules for application in the grid walls offer similar possibilities as our panel system and promote self-learning and training of the theoretical content during active, practical and instructional conditions. The modules allow themselves to be flexibly arranged on the wall-mount leaving the table area free for training literature and exercise books. The Experimental Plug-in System consists of electrical components in a Makrolon casing together with their associated overlay-masks. These masks, specifically dedicated to each experiment, allow only the opening of the relevant circuitry in the universal plug-in panel offering trainees a highly effective and transparent learning method during their period of basic training. Experimental Portable Systems Experimental Wall Systems 4 Our Experimental Portable System and Trainer consists of compact, portable cases most of which are fitted with their appropriate power-supply, measuring units and connection cables. Their mobility allows them to be used practically anywhere "in the field" thus avoiding costly commercial or educational premises and can be quickly and easily set up for operation, (please refer to our conventions of use) More complex systems, such as in the automotive or automation technology areas of study and further in the electrical braking and motor drive technologies, are reproduced by us as fully functional wall systems. These systems, most of which can be directly connected to the Trainee Metering Station, provide the student with a "live" working atmosphere.

5 Each different experimental system is conceived, designed and manufactured in direct accordance to the relevant didactical and methodical requirements. Through our consideration of professional practical experience in each topical area and the application of original automotive components, our systems are able to offer that feeling of "real life" conditions during the entire educational process. The distinctively printed and easily comprehensible markings for the circuit symbols, circuit diagrams together with the clearly and orderly arranged experimental assemblies makes even the most complicated circuitry easy for the student to follow and understand. The rigorous integration of safety devices, including all connector elements, guarantees a safe handling of the experimental units. A further comprehensive range of accessories is available. Didactically and exemplary conceived methods in the experimental instructions guarantee success in the deployment of the experimental units and the learning process. All systems are always flexibly integratable in our: Professional Practice Systems and Training Environment Furnishings Through our comprehensive programme for training environment furniture which we develop and manufacture inhouse, we are able to offer an optimal solution for every room and educational institution. Whether the systems are with aluminium or steel elements, as laboratory, computer or workshop fittings, with power supplies, experimental frames or wall mounts, with storage cupboards, stools or accessories for the training environment - ELWE has always got the right solution for your wishes. Experimental equipment and training environment furnishings make ELWE a competent all-rounder for turn-key training environments in educational facilities. ELWE Technik GmbH Elwestraße Cremlingen Germany Tel.: Fax.: info@elwe.com 5

6 World of automation...a quick word to our ELWE Technik consequently follows its philosophy that product development should be directed towards our customer requirements. It is therefore very important to us that you as customer can find the right product or application in our delivery programme which is best suited to your requirements. The student is given the possibility of experiencing the results of their programming work as it would be on full scale equipment and installations in real practice but under safe conditions. Whichever form of study is taken however, we would prefer to leave that up to the instructor. WIN SPS 6

7 "World of automation You have the opportunity to choose between three principle applications For this purpose, we are offering you Software simulation Hardware simulation and Equipment simulation All of these areas offer an optimum product for the budget available. Some examples are presented on the following pages. If required, we would strongly recommend that you seek the assistance of our field representatives... they will find a suitable solution for you. SPS-Software for System simulation Education is the future 7

8 Starter-Kit PLC-Trainer I for beginners incl. two plug-in cards and programm samples Complete set of PLC PLC is build into a declined housing. 2 plugin cards "Trafficlight control" and "Stepping motor" incl. program samples on CD belong to the set Easy and clearly arranged set-up Built-in power supply Connection socket for ELWE plug-in cards Inputs and outputs are available on 4 mm safety sockets Digital sensors and actors can be connected LED display of the input / output states Storage case Compatible with Siemens S7-300 Programmable with Siemens STEP7 Alternative: programmable with WinSPS-S7 Programming via RS232 or USB interface PLC-Trainer I for beginners Order No.: The company ELWE Technik offers a complete and comprehensive set-up with this Starter Kit at a reasonable price. The equipment not only includes the PLC but also the relevant software for learning the programming. The two actors provided enable the "Experimental Programs" to be immediately started or checked that they are working properly. Performance characteristics of the PLC Trainer for beginners I - III (VIPA SPS) In addition to the Starter-Kit PLC Trainer I for beginners which includes all the most relevant parts we also offer a range of different PLC Trainers for beginners. For this purpose we have built different versions of the PLC control enabling a universal connection of this device to other systems. Therefor we present different systems on pages 9 and 12 from which you can choose depending on your performance requirements or financial possibilities. * ELWE plug-in cards can be plugged directly onto the 50 pole connectors. ** A patch bay / adaptor onto which the ELWE plug-in cards can be directly plugged is available as an option for the Trainer II + III. *** Programming examples of the for the ELWE plug-in cards are on the CD. Additionally, the PLC control panel system can be adapted for table-top use with an angle support. 8

9 PLC-Trainer, for beginners PLC-Trainer I, for beginners PLC-Trainer, for beginners Easy and clearly arranged set-up Built-in power supply (further combinations on request) Digital- or relay outputs All digital inputs and outputs are available via 4 mm safety sockets Connection possibility for digital and analogue sensors Plug-on possibility for simulators of the PLC Trainers for beginners II / III for example the plug-in card digital or the plug-in card analogue LED display of the input and output states Compatible with Siemens S7-300 Programmable with Siemens STEP7 Alternative: programmable with WinSPS-S7 Programming via RS232 or USB interface Expandable up to 128 I/O points (PLC-Trainer for beginners II / III) The PLC-Trainers II / III are mounted on an A4 experimental panel which can also be hung on a mounting wall by means of the clamps at the back. Also the PLC-Trainer II / III can be mounted on the inclined grid and used as a tabletop unit. PLC-Trainer II, for beginners With 8 digital outputs Our training units in the PLC control area all have the following in common. They are easy to assemble, quick and simple to connect or wired up with their respective sensors and actors and they offer a full range of possibilities through the "live" presentation of activities with the respective PLC programs. The student can experience his own success in a quick and easy manner by using the smallest and most reasonably priced training setup which can take him through to demonstrating the operation on large complex installations with PROFIBUS connections. Because of all these possibilities which are offered by ELWE in the area of automation technology we would like to recommend that you contact us for a specific offer based on your necessities and requirements. Our field representatives are also always willing to offer assistance and give advice. A visit from them is completely free of charge. PLC-Trainer III, for beginners With 8 relay outputs Adaptor for ELWE plug-in-cards with 8xDI and 8xDO 9

10 LOGO! Training System Training System for Automation with components from SIEMENS (R) The Siemens logic module LOGO! is a programmable small control system and forms the basis of the LOGO! training system developed by ELWE-Technik GmbH. These training systems containing LOGO! components offer a very wide range of possibilities at a very reasonable price. Flexible operational possibilities for installation in either an experimental frame or wall mount with supplementary fittings. Basic panel for LOGO! Training System, voltage supply unit, extension module For exercises in laboratories, workshops or computer laboratories it can also be used as a table-top unit All extra-low-voltage signals (DC 12 V / 24 V) are carried on 2 mm safety sockets All low-voltage signals (AC 115 V / 230 V) are carried on 4 mm safety sockets. Outputs with electrically-isolated relay contacts or LED display ELWE system simulator (ASIMA) can be connected to the LOGO! Training System using a 50-pin flat cable The Logo! Training Systems allows the student to study practically the basics of digital engineering and control engineering. It offers various applications in the fields of digital engineering, installation engineering, automation, mechanical and apparatus engineering. It enables the easy input of control programs either in LAD (ladder diagram) or FBD (function block diagram), via button and LCD field (only FBD) or via the LOGO!Soft Comfort software when using a PC (LAD and FBD) LOGO! Training System Order No Other accessories such as literature, software and differing technical provisions are available Example of use: ELWE Technik offers you a fully comprehensive range of applicational possibilities in the area of automation technology. For basic training on the subject of PLC programming with our LOGO! Trainer together with other apparatus in this series, system panel assemblies can be implemented to represent simple operational procedures for example: Material sorting system with balls Sump pumps Lifts Electrical door drives Customer requirements and model prior to the production by ELWE We eagerly await a request for your personal product requirements. 10

11 S7-300-Trainer The SIMATIC S7-300 is a modular control system for system solutions with a main emphasis on production engineering. The wide range of assemblies are ideally suited to cope with all required demands and a flexible application is made possible through the easy realisation of decentralised structures and versatile networking capabilities. ELWE Technik has developed the S7 300 trainer with components from the S7 300 range enabling the students in their educational and further educational studies to find solutions to the complex and demanding tasks involved in automation technology. Example of an S7 300 Trainer presented here as a table unit with a sloping experimental surface, its main application is for student exercises. Central assembly of CPU components: various CPUs are available for application in different fields of control under which are CPUs with built-in in/outputs and the relevant functional capabilities such as CPUs with a built-in PROFIBUS DP interface Signal assemblies (SM) with both digital and analogue in/outputs Communication assemblies (CP) for bus coupling and point-topoint connections Function assemblies (FM) for rapid counting, positioning (controlled/adjusted) and control procedures The modular assembly technology of the S7 300 enables a flexible and service friendly deployment of the unit Experimental / T raining Topics Modular control system for the higher level of education offering the possibility to combine several different assemblies. Bus systems can be set up using the communication assemblies. Project planning, programming and communication of automation solutions. Because our products offer such a wide range of possibilities we recommend that you contact us for an offer for your requirements and specifications. Example of use: From the many automation units being offered by ELWE the S7 300 Trainer shown here is a control device for a linear unit with PROFIBUS connection. Our field representatives are always willing to provide assistance and offer advice on the capabilities of the ELWE S7 300 Trainer. 11

12 ASIMA (System Simulator for PLC) The advanced system simulator from ELWE is a further development of the much copied equipment simulator ASIM which has proven itself over many years. The equipment simulator can be used in connection with all PLC models with standard signal gain on the digital (24 V DC) and analogue (0 10 V DC) in/outputs. ASIMA with practice mask and pump equipment The 33 masks are subdivided into three separate sets according to the degree of difficulty in the PLC programming exercises. The range of exercises not only provide an introduction to automation technology for the student who has no previous knowledge in the application of small control units, but also enables the learning of demanding solution strategies applying the fully functional and extensive programmable memory control. The panel surface is subdivided into a clearly laid out field providing connections to the PLC, a demonstration field for overlaying a mask representing large equipment installations and a control field which is labled for the specific equipment. A microprocessor enables the transparent assignment of up to 12 digital in/outputs, 2 analogue in/outputs and 2 potentiometers to the operating field as well as to the sensors and actuators of the equipment represented on the current overlaid mask. Many installation simulations run automatically through the application of micro-processors enabling both a highly transparent method of demonstration for the equipments functions and an easy investigation of the PLC programming work. Experimental assembly incorporating an S7 300 Trainer and an ASIMA equipment simulator on an ELWE work place As in practice, the connection to the SPS can either be made using single connection cables and 2 mm safety sockets, 4 mm safety sockets, or alternatively and without any further set-up time, over a flat ribbon cable and a 50-pole connector strip. Basic equipment ASIMA (with 4 mm sockets), incl. folder for storage of masks and experiments on CD Order No Masks with different degrees of difficulty Set 1: Classical air gap switch circuits Order No Set 2: Industrial facilities Order No Set 3: process sequences with analog functions Order No Additionally required : PLC with the following minimum requirements: 12 inputs / 12 outputs (digital 24 V DC) 2 inputs / 2 outputs (analogue 0 10 V DC) e.g. Order No Practice related, 4 relay contacts enable the connection of coils for the safe regulation of the actuators indicated. As in normal practice, all switch and sensor functions can be mechanically singly switched, openly or closed, to the SPS to avoid circuit breakages. A row of 24 microprocessor controlled LEDs enable an easy reading of gain, movement, position etc. in the equipment schematic of the particular mask which is being applied. The functional status of the representative sensors and actuators under examination in the system on the selected mask is indicated by a bar of 36 microprocessor controlled red, yellow and green LED s dedicated to the digital inputs and outputs. Analogue functional proportions of the equipment such as the extraction speed of a silo content, the output volume of a pump or desired values can be selectively altered with a potentiometer in the control field or through analogue signals from the PLC. 12

13 ASIMA II (System Simulator for PLC) The ELWE ASIMA II is the logical further development of the ELWE (Standard) ASIMA. It can be used in conjunction with all PLC models with standard signal gains on the digital (24 V DC) and analogue (0 10 V DC) inputs and outputs. In contrast to the standard ASIMA these training units have been built onto the ELWE ComTec module. The representation of this particular equipment (they are identical with the masks of the Standard ASIMA) takes place on a monitor screen showing the relevant sequence of events. The special advantage is that the learner has the possibility of not only connecting the equipment to a monitor screen but can also connect it to a video projector enabling him to present it to the whole class. ASIMA II Here also, the 33 set-ups include varying grades of difficulty in connection with the setting up of the PLC programmes. The exercises cover such a wide range of gradients of complexity, from elementary control processes for complete beginners with no previous knowledge of automation technology, right up to the most demanding solution strategies by applying the complete operational spectrum of large programmable memory control. The system consists of a patch bay for wiring up to the PLC and an ELWE ComTec component with a labelled operating panel for the specific installation being applied. The assignment of the individual control buttons and switches for each particular installation called up are displayed on a monitor screen. The connection to the PLC can, as in practice, either be made using single connection cables and 2 mm safety sockets or 4 mm safety sockets. Examples taken from the list of project assignments As in normal practice, all switch and sensor functions can be mechanically singly switched, openly or closed, to the PLC to avoid circuit breakages. Equipment ASIMA II Order No Additionally required : PLC with the following minimum requirements: 12 inputs / 12 outputs (digital 24 V DC) 2 inputs / 2 outputs (analogue 0 10 V DC)) z.b. Order No The analogue factors of the equipment s mode of operation such as the discharging speed of silo content or pump. Reference values can be regulated with a potentiometer in the control field or through analogue signals from the PLC. This future oriented system has been developed by us. The integrated software for the range of equipment may be extended to fit any future demands. Monitor or video projector 13

14 Position Control / Linear drive Wherever precision and smooth running are concerned, linear guide systems for positioning functions play an important role. Linear technology finds applications in: Machining technology Special machine construction Mounting and handling technology Welding technology Medical technology Equipment linear drive with Profibus-DP The system is characterized by: Clearly laid out assembly PROFIBUS connection Manual and automatic operation Motor and signal transmitter can be easily exchanged Touch panel for operation and observation Safe operation with transparent covers for all moving parts Adjusting the position sensors Setting up the linear units Compilation and trial of own PLC programmes Educational and training unit for maintenance and fault finding applications Slide & Carriage Sensors Cable-potentiometer Absolute encoder The system "Equipment linear drive with Profibus-DP" consists of: A PLC as master for control and/or control processing Touch panel for menu-guided monitoring and/or control of the linear unit Frequency converter for the drive control and/or regulation Three-phase short-circuit rotor as drive Linear unit with drive mechanism, slide carriage, tape measure, limit switches and sensors Peripheral device ET200S for collecting/relaying the sensor and actuator signals Absolute encoder as a linear axis distance conversion module Cable potentiometer as position sensor of analog values Drive mechanism Limit switches Equipment linear drive with Profibus-DP Order No Determining positions via the touch panel Starting up and storing positions Distance determination via an absolute encoder Programming a touch panel Networking via PROFIBUS-DP Distance determination via analogue values with a cable potentiometer Shutting down the system by means of an emergency OFF device Positioning with control and/or regulation Manual and automatic operation Thanks to the modular construction, other signal collection modules can be flange mounted to the linear axis. 14

15 MCS - Models (Mechatronic Compact System) Gravity feed magazine Just as the name describes, our MCS consists of compact mechanical modules functioning as actuators for the PLC programming within the professional area of a mechatronic engineer. The model represents typical operational processes in step with practice such as those which occur in different areas of industry. This system also allows you to teach information and solutions in the field of automation. The MCS modules can be set up in combination with programmable logical controls to form systems of varying complexity. The different function modules are assembled on sturdy aluminium panels and can be arranged in various combinations and configurations depending on application requirements Swiveling object-transfer Undermentioned are a few examples of modules available: Gravity feed magazine (FMZ), Gravity feed magazine with test facility (FMZ-PE), Swivelling object-transfer device (SU), Analogue measuring device (MA), Sorting in three lines (SORT03), Processing: Drilling (BAB), Pick and place electrical 3 positions (PPE03), Pick and place pneumatical 2 positions (PPF02), Revolving object-transfer unit with test device (RST-PE), Storage with 3 magazines (LAG03). Analog measuring Altogether, 20 different modules can also be connected to each other via connecting channels. Storage with 3 magazines Processing: Drilling Preparation of parts Distribution of parts Transport of parts in linear way Transport of parts in circular way Processing of parts Inspection of parts Measuring of parts Sorting of parts Transport of parts between different stations Storage of parts Sorting in three lines Manual Service Unit Due to the complexity of our product range we kindly suggest that you order our special catalogue on the "Mechatronic Compact System" or request an offer for your specific requirements. If you want we can send you our field representatives who can offer you comprehensive advice on this subject free of charge. Control console 15

16 Process and Field Communication PLC AS-Interface / PROFIBUS-DP with MCS models The Mechatronic Compact System for the professional field of Mechatronics consists of MCS modules, which allow you to practically demonstrate typical processes as they appear in various industrial branches. This system also allows you to teach information and solutions in the field of automation. A programmable controller is necessary as a master for driving the Mechatronic Compact System. A simulation of practice oriented production control can be established by the interconnection of the related interface assemblies of the industrial bus systems PROFIBUS DP or the AS Interface. The recommended linear system is supplied pre-mounted and preprogrammed. Because of the modular assembly, the systems can be extended at any time with the interface assemblies and Compact Modules. Programming of bus systems Setup, operation and maintenance of mechatronical units Combination of bus systems Preparation of parts Distribution of parts Transport of parts in linear way Transport of parts in circular way Processing of parts Inspection of parts Measuring of parts Sorting of parts Transport of parts between different stations Storage of parts For our MCS - Models we keep a detailed retail catalogue. If you are interested, please contact our sales representative. Please request an offer from us for your own personal requirements and specifications. 16

17 Servo drive and brake system Embedded PC-Version for three-phase, DC and AC motors The servo drive and brake system (Embedded PC-Version for three-phase, DC and AC motors), consisting of a modern PC-based industrial control and a drive device with a synchronous servo motor which communicate via Profibus, offers a multitude of possibilities for studying the characteristic features of electrical machines. Three-phase asynchronous motors of varying power classes can be used as test units. The visualising software allows the system to be controlled either manually or automatically. For three-phase, DC and AC motors Compact assembly allows a short set-up time. Practical industry-compatible design Flexible, also in the future, thanks to embedded PC Easy operation Manual and automatic operation Graphic user interface PC-based industrial control (PROFIBUS) Settings, control and direct measurement acquisition via PC Servo with 2.2 kw Parameter setting Load characteristic recording of electrical machines such as e.g. Hoist Flywheel Pump/Ventilator Winder Mill Traction (traction drive) Compressor/Piston pump Roll stand Lathe or free input Additional recording possibilities or free input Motor characteristic Temperature progression (*) Nyquist diagram Nyquist diagram Motor characteristic (*) with an accordingly equipped motor under test Servo drive and brake system for DC and AC motors Order No

18 Servo drive and brake system Experimental panel and Table-top unit for 300 / 1000 W machines Parallel to the Embedded version, ELWE Technik GmbH still maintains a compact system as a panel or housed version in its delivery programme. The system consists of a control unit which regulates the synchronous servo motors and serves additionally for measuring the revolution speed, torque and voltage current of the machine being investigated. The system includes a compact AC servo device for driving, stopping and braking the ELWE machines. As a special bonus, the included system software has been extended for load simulations (lifting gear, calenders, pumps and ventilators) in Measurement display and analysis of the machine parameters, characteristic diagrams, filing data on the PC, r.p.m. and torque regulation, automatic registration of characteristics, simulation of centrifugal masses. Equipment incl. software and accessories (without test sample) Servo drive and brake system 300 W Option: Experimental panel Order No Servo drive and brake system 300 W Option: Table-top unit Order No Servo drive and brake system 1000 W The control unit for the 1000 W class is only available as a tabletop unit. Order No

19 Electrical Structure of Machines The experimental panel system "Electrical Structure of Machines" is used to demonstrate the principal structure and action of electrical machines. The most important DC, AC and threephase motors/generators can be constructed by using separate components. The individual components of a machine are mounted to form a working motor or generator in full visibilty on a base panel allowing a thorough investigation of their operation and characteristics. The motor r.p.m. metering installation for registering the revolution speed dependant variables is built into the base panel. Structure and operating principles of DC, AC and three phase machines. Investigation of the operating behaviours and characteristics. Equipment Electrical Structure of Machines Order No

20 Electrical machines in general Already 30 years ago, ELWE set new accents for the application of electrical machines in experimental lessons, which have meanwhile become generally valid. Large machine sets which could only be applied for demonstrational purposes containing a certain amount of risk had been substituted by less powerful machines with characteristic curves that are also typical for powerful machines. ELWE magnetic powder brake allows the measurement of static and starting torques. Since the products have consistently advanced in the following years, ELWE can now offer an extensive tutorial system on the subject "Electrical Machines and Drive Engineering" including numerous innovations and equipments. On the preceding pages we have already mentioned the products for our "servo drive and braking systems" together with the basics for our "Electrical Structure of Machines". Now follows the special features under the subject of electrical machines. Experimental electrical machines The type series of experimental electrical machines contain almost all field-experienced, electrical machines used in industry and in home appliances. In order to meet all groups of addressees ranging from the field of professional education to the courses of study at universities - and the requirements of demonstrations in classrooms or lecturerooms and in students excercises and courses of practical work, ELWE provides machines of the power classes 300 W and 1000 W. All machines can be used to record characteristics or to examine the operating performance and they can be applied in experimental set-ups on the subject of contactor circuits and closed loop control. Magnetic powder brakes For loading the machines, ELWE provides magnetic powder brakes with appropriate control units, which have been proved for many years and are easy to handle. Thus it is possible to measure torque and speed in the 1st and 3rd quadrants of the examined machines (motor operation). Experimental panel system "Electrical Machines" The experimental panel system "Electrical Machines" is mainly used for the application of experimental electrical machines for demonstration purposes in classrooms and lecture rooms. The individual units of an experimental set-up are connected via 4- mm safety sockets which are arranged in large, synoptical graphical symbols or current flow diagrams. ELWE alternatively provides an experimental module system and an experimental panel system PU for the application of experimental electrical machines in students' exercises and courses of practical work. The individual units, where possible, are connected directly to commonly used industrial switchgear via 4 mm safety sockets as in practice. The following pages present a summary of the contents in the experimental manual relating to the available equipment together with their testing and learning contents. 20

21 Manual Three-phase AC Basic Circuits and Transformers Experimental group: Three-phase AC basic circuits Star connection with resistors without neutral conductor Star connection with resistors and neutral conductor Star connection of resistors in case of unbalanced load Delta connection of resistors Experimental group: Transformers Single-phase transformer, no-load and load Single-phase transformer, short-circuit voltage and sustained short-circuit current Single-phase ring core transformer, no-load and load Single-phase ring core transformer, short-circuit voltage and sustained short-circuit current Single-phase auto-transformer, operating characteristics Three-phase transformer, Yy0-connection Three-phase transformer, Dy5-connection Three-phase transformer, Yd5-connection Three-phase transformer, Yz5-connection Single- and three-phase transformer (induction motor with slip-ring rotor) Experimentieranleitung Manual Manual Three-phase AC Basic Circuits and Transformers Order No Manual DC Machines Experimental group: DC shunt-wound motor Connection, starting, change of rotation Rating plate data The influence of the reversing pole and the compensation winding on the brush light. Load characteristics Speed and exciting current characteristic Speed and voltage characteristic Speed and torque characteristic at different armature voltages Speed and torque characteristic at different armature series resistance values Experimental group: DC shunt-wound generator Separately-excited: connection, change of rotation Self-excited: connection, change of rotation Leonard set, Leonard circuitry, connection and counter connection Separately- and self-excited: load characteristics No-load characteristic Leonard set, no-load characteristics Leonard set, load characteristics Experimentieranleitung Manual Experimental group: DC series-wound motor Connection, starting, change of rotation Speed control Load characteristics Single- and three-phase rotary transformer (induction motor and slip-ring rotor) 21

22 Manual DC Machines - continuation Experimental / T raining Topics Experimental group: DC series-wound generator Connection, change of rotation Load characteristics Experimentieranleitung Manual Experimental group: DC compound-wound motor Connection, starting, change of rotation Load characteristics Compound characteristics Experimental group: DC compound-wound generator Connection, change of rotation Load characteristics Compound characteristics Manual DC Machines Order No Manual AC Machines Experimental / T raining Topics Experimental group: Capacitor motor Starting behaviour Connection, change of rotation Starting connection with centrifugal switch Starting connection with starting relay Rating plate data Load characteristics Starting characteristics Experimental group: Single-phase induction motor with auxiliary resistance winding Starting behaviour Connection, change of rotation Load characteristics Starting characteristics Experimental group: Split-pole motor Connection Load characteristics Starting characteristics Experimentieranleitung Manual Experimental group: Repulsion motor Connection, brush shift, change of rotation Load characteristics Experimental group: Universal motor Connection, change of rotation Load characteristics at DC and AC voltage Speed and torque characteristic at DC and AC voltage 22 Manual AC Machines Order No

23 Manual Three-phase Machines Experimental group: Three-phase induction motor with squirrel-cage rotor Connection, change of rotation Star-delta connection Rating plate data Kusa connection Compensation of reactive power Steinmetz connection: Load characteristics Steinmetz connection: Starting characteristic Load characteristics Starting characteristics Subsynchronous and hypersynchronous operation, moving in opposite directions Experimentieranleitung Manual Experimental group: Three-phase induction motor with slip-ring rotor Rotor voltage, rotor current, rotor frequency Connection, change of rotation Rating plate data Load characteristics Starting characteristics at different resistance values of the rotor starter Speed characteristic Experimental group: Three-phase induction motor, pole-changeable, Dahlander circuit Connection, change of speed Load characteristics: at low speed Load characteristics: at high speed Starting characteristics: at low and high speed Experimental group: Three-phase induction motor, pole-changeable, 2 separate windings Connection, change of speed Load characteristics: at low speed Load characteristics: at high speed Starting characteristics: at low and high speed Experimental group: Three-phase synchronous motor with smooth-core rotor Connection, starting Load characteristics Load characteristics at cosϕ n = 1 constant V-Characteristic Experimental group: Three-phase synchronous generator with smooth-core rotor Connection Synchronizing circuits (light-dark circuit) Synchronizing circuits with double frequency meter, double voltage meter and zero voltage meter Synchronizing circuits with double frequency meter, double voltage meter and synchronoscope No-load and short-circuit characteristic Load characteristics Exciter-regulator characteristic Experimental group: Three-phase synchronous motor with salient-pole rotor Connection, starting Load characteristics Load characteristics at cosϕ n = 1 constant V-Characteristic Experimental group: Three-phase synchronous generator with salient-pole rotor Connection Synchronizing circuits (light-dark circuit) Synchronizing circuits with double frequency meter, double voltage meter and zero voltage meter Synchronizing circuits with double frequency meter, double voltage meter and synchronoscope 23

24 Manual Three-phase Machines - continuation No-load and short-circuit characteristic Load characteristics Exciter-regulator characteristic Experimentieranleitung Manual Experimental group: Reluctance motor Connection, change of rotation Load characteristics Starting characteristics Experimental group: Protection of electrical machines Motor protection with motor protection switch Motor protection with motor protection relay Machine protection with built-in temperature switch Machine protection with thermistor Manual Three-phase Machines Order No Manual Control of Electrical Machines Experimental group: Limit and proximity switches Mechanical limit switch, operating mode Inductive proximity switch, operating distance Capacitive proximity switch, operating distance as a function of different material Optical proximity switch (push-button system), operating distance as a function of different material Application of mechanical limit and proximity switches on the example of the reversing contactor connection Experimentieranleitung Manual Experimental group: Contactor circuits Control of a motor (automatic control) Control of a motor from two actuators Contactor circuit with motor protective relay and fault signal Bridging of a motor protective relay during starting time at heavy starting duty of motors Automatic Kusa circuit Reversing contactor circuit Automatic reversing contactor control Positive sequence control for 3 belt conveyors Dahlander circuit Pendulum contactor circuit Automatic star-delta circuit Multifunctional relay Contactor circuit with multifunctional relay Experimental group: Protective circuits Avoidance of unintentional operation Immobilisation of the start button Emergency tripping device in the control circuit for simple drives Emergency tripping device in the control circuit to interrupt several electric circuits Two-hand control type 1 Two-hand control type 2 24

25 Manual Control of Electrical Machines - continuation Experimental / T raining Topics Experimental group: Electronic switching and motor control devices Electronic motor starter Electronic three-phase load disconnecting relay DC braking of a squirrel-cage motor Experimentieranleitung Manual Manual Control of electrical machines Order No Manual Fault Simulators Experimental / T raining Topics Experimentieranleitung Manual Experimental group: Fault simulator for contactor circuits On/off circuit Reversing contactor circuit Reversing contactor circuit with limit switches Automatic star-delta circuit Dahlander circuit Automatic Dahlander circuit Automatic Dahlander reversing circuit with limit switches Experimental group: Motor fault simulator Fault finding at the three-phase induction motor with squirrel-cage rotor Selectable faults: winding interruption, interturn short-circuit, body contact, winding short-circuit Manual Fault Simulator for Contactor Circuits is part of the equipments (for 300 W) or (for 1000 W) Manual Automatic compensation of Reactive Power Experimental / T raining Topics Experimentieranleitung Manual Experimental group: Automatic compensation of Reactive Power Capacitors in star connection Capacitors in delta connection Currents in a compensated, electric plant Compensation of reactive power and power factor Overcompensated, electric plant Calculation of step power for compensation plants Automatic compensation of reactive power of a motor with resistive load and inductive load Causes of faults in a compensation plant with reactive power regulator Automatic compensation of reactive power of a system with resistive load and inductive load Manual Automatic compensation of Reactive Power Order No

26 Summary of available machines and equipment. (Machines, Masks, Brakes, Gyrating masses, Experimental Systems, Switches) DC Machines (230 V) Power class 300 W/1000 W DC shunt-wound machine DC series-wound machine DC compound-wound machine Multifunctional DC machine AC Machines (230 V) Power class 300 W/1000 W Capacitor motor with centrifugal switch Single-phase induction motor with auxiliary resistance winding and centrifugal switch Repulsion motor Universal motor Three-phase Machines (400 V Three-phase Systems) Power class 300 W / 1000 W Three-phase induction motor with squirrel-cage rotor, 400/690 V Three-phase induction motor with squirrel-cage rotor, 230/400 V Three-phase induction motor, pole-changeable, Dahlander circuit Three-phase induction motor pole-changeable, 2 separate windings Three-phase induction motor with slip-ring rotor Three-phase synchronous machine with smooth-core rotor Three-phase reluctance motor Three-phase Machines (230 V Three-phase Systems) Power class 300 W / 1000 W Three-phase induction motor with squirrel-cage rotor, 230/400 V Three-phase induction motor, polechangeable, Dahlander circuit, 230 V Three-phase induction motor, polechangeable, 2 separate windings, 230 V Three-phase induction motor with slip-ring rotor Three-phase synchronous machine with smooth-core rotor Three-phase reluctance motor Note: If you want we can send you an offer free of charge for these machines and apparatus including their power supplies and measuring units according to your requirements. 26

27 Three-phase Machines with multifunctional asynchronous / synchronous Machine (400 V Three-phase Systems) Power class 300 W/1000 W Three-phase induction motor with squirrel-cage rotor, 400/690 V Three-phase induction motor with squirrel-cage rotor, 230/400 V Three-phase induction motor, polechangeable, Dahlander circuit, 400 V Three-phase induction motor, polechangeable, 2 separate windings, 400 V Three-phase reluctance motor Multifunctional three-phase asynchronous/synchronous machine Three-phase Machines with multifunctional asynchronous / synchronous Machine (230 V Three-phase Systems) Power class 300 W/1000 W Three-phase induction motor with squirrel-cage rotor, 230/400 V Three-phase induction motor, polechangeable, Dahlander circuit, 230 V Three-phase induction motor, polechangeable, 2 separate windings, 230 V Three-phase reluctance motor Multifunctional three-phase asynchronous/synchronous machine Three-phase synchronous machine with salient-pole rotor (230/400 V) Power class 300 W/1000 W Three-phase synchronous machine with salient-pole rotor for motor and generator operation Three-phase Induction Motor for Machine Protective Systems (230/400 V) Power class 300 W/1000 W Three-phase induction motor with built-in temperature sensors. Sensors included into the windings: 1 Pt 100, 3 PTC, 3 temperature switches. Additionally 1 temperature switch for protection of the motor Performance Features of Electrical Machines: Solid industrial-type units in compliance with the type of construction B3 All machines meet the recent state of international standards, e.g. DIN-VDE 0530 Protection system IP 54/ insulation class F Solid aluminium casting profiles Elastic coupling collars Covered Rotating shaft ends 4mm safety sockets in the lid of the terminal box Modular design of the system 27

28 Fault Simulator for Contactor Circuits A fast elimination of faults occuring in control circuits with contactors presuppose a systematic and rational trouble shooting. By means of the fault simulator, developed by ELWE, the required knowledge can be deepened and the necessary experience for purposeful trouble shooting can be gained by practising. Trouble shooting direct trouble shooting at the measuring points on the current flow diagram of the used mask Trouble shooting on a special mask which displays the devices of the circuit including its connections and designations in a practice-oriented way Fault Simulator for Contactor Circuits 300 W Order No Fault Simulator for Contactor Circuits 1000 W Order No Essential accessories: Different induction motors, Masks, gears, clutches, safety cables and an experimental manual. Compensation of Reactive Power The power supply companies try to run their systems with as little reactive power as possible. Therefore, especially industrial companies use central compensation systems which automatically connect and disconnect capacitor groups according to the connected current-consuming equipment with inductive components (motors, transformers). The structure and method of operation of such systems can be examined by means of this equipment in a practiceoriented way. Compensation of Reactive Power 300 W Order No Compensation of Reactive Power 1000 W Order No

29 Power Electronics Base grid system The functional components for the complex circuitry of the power electronics are assembled and plugged onto a universal plug panel which incorporates 4 mm / 2 mm plug sockets arranged in 19 mm grid form. The 4 mm sockets are for the required operating power supply, the 2 mm sockets are for the transmission of the signals from the input to the output of the circuitry. Every component forms a functional unit which represents a complex power electronics circuit when combined with further components. The logical structure of the circuits enables the signal to be followed from its source to its transduction for further appropriate processing. The open structure allows visual contact with the functional components. Because the signals are running over 2 mm experimental cables, the trainee can conduct an exhaustive analysis of the circuit. Basic principles of power electronics Diodes and thyristors in DC and AC circuits and alternating current circuits Phase controlled modulation Rectifier circuits Please request an offer from us for your own personal requirements and specifications. 29

30 Power Electronics Experimental Module System The experimental module system from ELWE is a training system for students covering the subjects of mains rectifiers and 4-quadrant DC drives. The mains rectifiers are built of individual diodes and thyristors and tested using measurements. The operating modules, fitted with hooks for hanging on a grid wall, are interconnected with safety cables via their 4mm sockets to form a complete power electronic circuit. The power supply connection is on the side of the module. The flexible arrangement of the operating components allows the instructor to set up different functioning power electronic circuits. The module system incorporates all the necessary operating units required in modern power electronics. Power Electronics experimental module fitted with clamps for hanging on a grid wall Converter valve Converter valve circuit for rectifying Converter valve circuits for rectifying and/or inverting Electronic AC power controller Phase controlled modulator Multicycle control One-, two-, four-quadrant current direction Frequency converter Please request an offer from us for your own personal requirements and specifications. 30

31 CTT-Case In order to keep the education as flexible as possible, we are offering the topic of Power electronics in the compact form of a case. The complex circuitry is made up of operating components connected to each other via 2mm connector cables. The spacious arrangement of these operating components on the plug panel allows a coherent demonstration of the functional relationships. The case permits either the trainee and/or small groups to carry out their own experiments therefore augmenting the didactical value which produces much higher levels of success and achievement. CTT Case System with Insert tray ET Power electronics The insertion panel ET combines 2 operating amplifiers which can be circuited to different types of controllers via a resistor and condenser field, a set point sensor, a matching amplifier, a power amplifier, all necessary half and full controlled bridge circuits, inductive loads, a full wave control unit, and a 4 pulse phase modulator control unit. The ET insertion panel provides not only an aid to investigating the current converter circuits and their drive modes but can also be set up as a complete regulator circuit with a current converter as actuator. Even the assembly of an under current operating rotational speed regulator of a DC motor is possible. Built into the CTT case (basic unit) are all the necessary measuring instruments and voltage/signal supplies. Basics of current converter technology Diodes and thyristors in direct current circuits Thyristors in alternating current circuits TRIAC in alternating current circuits Bridge circuits Direct current drives CTT Case System, Basic unit Order No Insert tray ET Power electronics Order No

32 Mains Rectifiers The equipment used for the experiments on the "Mains rectifiers" topic which has been developed by ELWE is outstanding in having many excellent performance characteristics: Using only two experimental panels and the appropriate masks, fifteen different wiring systems for mains rectifiers can be investigated. The use of masks makes it possible to show bigger circuit arrangements, opened up and to a large extent visible. All the points relevant to understanding the circuits, such as, for example, the gate, anode and cathode connections are accessible and may be used as measuring points via 4 mm safety sockets. A control unit and a power unit for the tested rectifier circuit are set up on separate experimental panels. The control signals are transmitted with the aid of a 37-wire round cable. The experimental panels incorporate their own voltage source for the control electronics. From a long list of possible subjects, we would like to emphasise the following themes: One-way rectification with a power diode Single-pulse centre point circuit, uncontrolled Two-pulse, bridge circuit, uncontrolled Three-pulse, centre point circuit Six-pulse, bridge circuit Thyristor Single-pulse, centre point circuit, controlled Two-pulse bridge circuit, controlled Three-pulse, centre point circuit, controlled Six-pulse, bridge circuit, controlled Equipment Mains Rectifiers Order No Possible test setups Supplementary Equipment Mains Rectifiers Order No ** For all experiments a suitable power supply and a corresponding load is necessary. Please request an offer from us for your own personal requirements and specifications. 32

33 DC Chopper The DC-chopper equipment developed by ELWE Technik GmbH allows a thorough and visible demonstration of the functional dependencies between the electrical DC chopper volumes and the standard power semiconductors and load types. The actual equipment consists of three control panels built into an experimental stand The first experimental board together with the control unit and masks, allows four circuit variants to drive the apparatus: manual control via analogue inputs V DC via 8 bit PLC or PC inputs or by using the built-in speed control with secondary current control for DC drives. The Power unit I, as second experimental board together with control unit and masks contains the four most commonly used power semiconductors: Darlington Transistor GTO FET IGBT The third experimental board with the Power unit II contains the classic thyristor with ring circuit. DC Chopper control unit Order No Signal transmission between control and power units allows a choice between the classical two-wire cable or the modern opticalfibre link. Power unit I Order No Power unit II Order No ** For all experiments a suitable power supply and a corresponding load is necessary. Please request an offer from us for your own personal requirements and specifications. Experimental / T raining Topics DC chopper different power semiconductors with thyristor control with resistive load DC chopper with mixed load (RL-load) and two-position control DC chopper with motor load and speed control with secondary current control 33

34 Pulse-Width Modulation In order to control the rotational frequency of electrical machines with the smallest possible losses, the pulsewidth modulation process is mainly used. In DC machines the rotational frequency control is achieved by simply reducing the DC voltage in the squarewave voltage pulse. In three phase induction machines the pulse / pause ratios of the square-wave voltage pulses must be so varied that due to the inductive effect of the machine coils a sinusoidal current results. Using the ELWE experimental panel "Pulse-Width Modulator" one may vividly show both processes and investigate very clearly the functional connection of the individual inputs with very little effort. The experimental panel incorporates two generators. One generator may be adjusted to produce a variable DC voltage or alternatively a square-wave or sinusoidal reference voltage. The frequency is 100 Hz. The second generator produces a triangular voltage, whose frequency can be varied in six steps ranging from 8 times to 256 times the frequency of the sine-wave reference voltage. Comparing the two generator voltages with a comparator produces a pulsed voltage at the comparator output. The generator voltages, the pulse-width-modulated voltage and the load current can be detected via 4 mm safety sockets. How they change with respect to time can be shown with an oscilloscope or with the help of a measuring interface and a PC. Note: ELWE also provides as an aid for this purpose, a data registration system with interface and buit-in PC. Experimental / T raining Topics Supplying the generator voltage I Wave form Frequency Generator voltage II Frequency Measuring the voltagesignals Comparator function Forms of the pulsed voltages at the comparator output with different kinds of loading. Pulse-Width Modulator - Experimental Panel Order No Pulse-Width Modulator - Plug-in Element Order No

35 Switching power supplies Basic unit with mask Forward converter A switching power supply is a compact unit for converting an electrical voltage. For instance, it can produce a direct voltage current from the mains voltage current (AC/DC converter). The circuit principle also works with a direct voltage current at the input when a smaller or larger output voltage is required (DC/DC converter). Power supply units commonly include a transformer for the electrical isolation of the input and output. The maximum transmissible power level rises, by constant saturation, with the frequency. Switching power supplies are used mainly in industrial installations because of their ability to reach a high power density. Nowadays because of continually falling prices, they are becoming more commonly used in small electronic devices such as computers, battery charger units or halogen lighting systems. Because of the higher switching frequency in tacted switching power supplies (ca. 20 to 200 khz), they have a higher efficiency (over 90 %) and can be assembled in a much lighter and compacter form. The voltage is converted by a transformer or, by some DC/DC converters through the periodic loading and unloading (PWM) of the inductivity being used as energy storage. There is just so much energy periodically stored in the inductivity necessary for a solid loading. This inductivity can be produced through the transformer itself or through an additional storage throttle. The output voltage must be filtered to achieve the smoothest possible direct voltage. To enable the most thorough investigation of the operating modus of switching power supplies, ELWE has developed a depictive training system incorporating all the most relevant variations of voltage conversion. Examples of training masks Experimental group for - Flyback converter Buck converter Boost converter Buck-boost converter Blocking oscillator type converter with potential separation Experimental group for - Forward converters Single transistor forward converter I Single transistor forward converter II Push-pull forward converter, full-wave rectifying Assymetrical half-bridge forward converter Symetrical half-bridge forward converter Full bridge forward converter Frequency converter / H-bridge The training system consists of two experimental panels (blocking oscillator type converter/flow converter) as a basic unit and the compatible overlay masks with the most important power semiconductors and basic circuits. An oscilloscope can help to follow the conversion of the voltage all the way from the input to the output. Switching power supplies - Flyback converter Order No Switching power supplies - Forward converters Order No

36 Drive Technology (AC/DC) Servo drives distinguish themselves by enabling very high levels of dynamic and accuracy under excessive loading to be achieved at high revolution speeds in modern drive technology. Highest demands on dynamics, r.p.m. accuracy, torque constancy, synchronisation angles or positioning accuracy could never be achieved without such complex mechanisms. Typical applications would be drives in electrical tools, printing machines, packing machines and robots with high clocking speeds. Servo drives consist of a servo motor and its servo-electronic; currently, and virtually without any exceptions, the motors produce today are commutated motors, EC-motors, permanently excited synchronous motors, brushless DC motors or AC synchronous motors. The training system, which ELWE has developed, incorporate the most modern industrial components. Servo drive with rotation unit Illustration of the output voltages, currents and the brake chopper control signals. Illustration of the intermediate circuit voltage of the current and the brake chopper control signals. Programming the servo control unit (delay and acceleration time, torque limit, speed display) Programming the speed control Displaying the dynamic process Programming the positions Servo drive with linear unit Illustration of the output voltages, currents and the control signals Illustration of the intermediate circuit voltage of the current and the brake chopper control signals Programming the servo control unit (delay and acceleration time, torque limit, speed display) Programming the speed control Displaying the dynamic process Programming the positions Reference travel End-of-travel limiting with control key Programming the travel profile Please request an offer from us for your own personal requirements and specifications. 36

37 Frequency converter The increasing trend in automation, parallel to the current demands for reduced energy consumption for the sake of the environment and rising energy costs, is a premise for the application of this technology in virtually all areas of machine and equipment manufacture which involve constantly variable settings of revolution speed and torque. Presently, mainly variable r.p.m. drives with three-phase or asynchronous machines with pre-circuited frequency converters are employed for this purpose. Within the framework of our integral modular product concept from basic training to further education in the area of automation technology, ELWE can supply experimental panels and modules fitted out with frequency converters from different manufacturers. The application of the Micromaster Series from Siemens means that the complete range has the same parameter structure. The order of command in the Micromaster Series is constantly a subset of the command order of the next higher row. All controllers can either be operated either individually or in combination within the automation system. They can be networked and integrated via TIA (Totally Integrated Automation) with other automisation components such as the S7-300 from the PLC range and the Touch Panels from Siemens when operating over optional PROFIBUS interfaces. The experimental panels and modules from ELWE with MICROMASTER frequency converters can be employed in countless experiments involving the control and regulation of the rotational speed of 230V three-phase motors. In order to enable the practical investigation of the properties and advantages of drives which are fed from a frequency converter, ELWE offers a complete and comprehensive accessory programme including a linear axis and a rotation axis which can be equipped with different sensors and actuators. Putting the frequency converter into operation Setting the parameters of the frequency converter Application of the frequency converter: with rotation unit with linear unit Please request an offer from us for your own personal requirements and specifications. 37

38 Laboratory Furnishings & Training Station Furnishings In addition to around 5,000 different products for training systems and appliances, ELWE Technik GmbH offers a multitude of standardised possibilities for laboratory furnishings to satisfy all customer demands. Parallel to the standardised items we are also capable of producing customised products in our own furniture workshops where individual requirements can be manufactured in a variety of materials such as aluminium, steel pipe, wood and plastics. You can choose within a wide range of possibilities where, but quite naturally, you can submit plans for your own special environment e.g. front panels on which all necessary connections for mains, PC networks and compressed air can be installed together with the possibility of integrating metering units and power supplies into the assemblies themselves. One of our most innovative systems is a multifunctional, mobile "Training Station" which presents virtually unlimited applicational possibilties in all areas of training and advanced education. In practical terms this means that our practice related systems can be planned, installed, extended, if necessary programmed or parametered and finally tested for nearly all areas of the study curriculum. The mobile training station offers huge economical advantages over classical tutorial environments in laboratories and training workshops including the possibility to apply various and flexible training methods. If you want, please contact our sales staff to assist you in the conception and planning of your class-rooms. Classroom furnishings from ELWE, the elegant, efficient and practical solution for your training environment. - - High quality - - Ergonomic - - Practical Robust - - Low cost