SOLUTIONS - Moeller Electric Parts

SOLUTIONS17SOLUTIONS18An exactly defined volume of dryair is passed through the plastic granulesto be dried, so that this adsorbs the moisture fromthe granulate over the set period of time.In order to dehumidify the air, this is passedthrough a molecular sieve consisting of zeloithewith a high capacity to adsorb watervapour. Once the saturation point of themolecular sieve is reached, it is heated up to 250°C according to a fixed temperature curve and thusregenerated.THE COMPANYSIMAR GmbH, with headquarters inVaihingen/Enz, was founded in 1977. Thecompany has grown and evolved on thebasis of innovative and pioneering bulkmaterials technology. Close cooperationwith customers has led to the developmentof systems for conveying, drying andblending an extremely wide range ofbulk materials. Not just for the plasticsindustry, but also for use with foodstuffs,pharmaceuticals and chemicals. Nomatter whether you work with granularor powder bulk materials, Simar alwaysoffers sensible alternatives to conventionalsolutions. Simar has branches or sales andservice partners in over 30 countries.( www.simar-int.com )Scalability of the easy familyAn MFD-Titan device with a double relayexpansion is already enough for the smallestdrier type. If several drying silos are used, theMFD-Titan is simply expanded with an easy800device linked via easyNet. In this way, up to fivedrying silos can be connected up without anyproblem. The drier version with automatic loadadaption is a special highlight. Depending on thesupply and the return temperature, motorisedflaps are controlled and visualized with theMFD-Titan. For this Simar uses the easyControlcompact controller, which can be networkedeasily via easyNet with the controllers already inplace. In this way, any requirement can be metquickly and cost-effectively. With programmingin compliance with IEC61131-3 easyControloffers a highly flexible program structure usingeasySoft-CoDeSys. The function blocks providedin the standard library and the easyControlclosed-loop control library can be combinedsimply with user-defined POUs.The PID controllersThe core of the program is made up by the PIcontrollers. A PI controller with a downstreamPWM function block is used for controlling theregeneration and adsorbtion heating. Dependingon drier type, up to seven PI controllers arerequired. The control loop of the adsorbtionheating presents a particular challenge. Asthe control circuit responds extremely quickly,there is a risk that the granulate may overheat.However, this problem can be solved simply witheasy closed-loop controller function blocks. Thetemperature setpoint and drying time are setvia the MFD-Titan according to the material. Ifnecessary, users can also store the closed-loopcontroller parameters in password-protectedmenus. The process air heaters are controlled bysemiconductor relays.Online language selectionIn an initial step the application was createdin four languages (German, English, Frenchand Spanish), which can be selected duringoperation. Other languages (Polish, Czech,Rumanian, Hungarian, Russian, Bulgarian, Dutch,Portuguese) were added at the customer‘srequest. All languages are stored in an easyprogram and are thus easy to maintain. Whenthe program is loaded, the user selects whichlanguage group of four languages each areto be assigned to the MFD-Titan. Germanand English are obligatory in every languagepackage.Connection to bus systemsThe Moeller easyControl also features anEthernet interface in addition to the busmodules for Profibus-DP, CANopen, AS-Interface,DeviceNet. This allows the KTX driers to beconnected easily to a higher-level PLC or a hostcomputer. Different accessories of the KTX driersallow adaption to customer requirements.Quicklink ID:MS1814CONCLUSIONHarald Weinert, technical manager atSimar GmbH explained:“The minimum space requirement,the high degree of flexibility and theprice /performance ratio reinforced ourdecision to use the easy device familiesfor the implementation of a new controlgeneration. A customer-friendly menuguidance with multi-lingual plain textdisplay, the remote diagnostics andteleservice features, as well as theflexibility provided for future systemexpansions were important criteria for usduring the development phase. Thanksto the easy family we were able tocombine a host of customer and processrequirements in a single control system.”Vetter-Steuerungstechnik is a newowner-operated company based inPfinztal which has established itselfon the market in the field of specialmachine programming. As ChristianVetter explained, “Products of theeasy family are ideal for Simar KTXdriers. Their modular design allows usto fit different drier sizes with exactlythe right control system. easySoft andeasySoft-CoDeSys offer us two powerfulprogramming user interfaces with a hostof ready-to-use function blocks. Theysimplify our programming requirementand thus reduce development costs.”(www.vetter-steuerungstechnik.de)For Moeller Electric Sales and Support call KMparts.com (866) 595-961619