SOLUTIONS - Moeller Electric Parts

SOLUTIONS18Less is moreCooling requires energy. Efficient coldproduction is vital for economicalrefrigeration. Furthermore an optimiseduse of energy also ensures a low emission ofenvironmentally harmful CO 2 . Frigel buildsenergy-efficient compression refrigerationsystems and also designs all its componentsincluding the control concept so thatresources are used economically duringoperation. The refrigeration systems alsohave to be robust and reliable. This is becausecustomers are also considering costs notonly in terms of acquisition costs but alsoparticularly in terms of running costs overthe lifetime of the system. The electricalcontrol and switching devices are exclusivelyfrom Moeller. Frigel values the ruggednessand reliability of the device, and Moellerwas chosen particularly on account of theprice/performance ratio of its products and itsoutstanding service.Regulated coolant circulationDepending on the refrigeration outputrequired, Frigel offers systems with one tofour cooling compressors which ensure thecontinuous circulation of the refrigerant.The most frequent systems used have twocompressors.After the system is started, the firstcompressor is started via a DS6 soft starter.Ensuring continuous cold production: Two coldcompressors with control cabinet and operator unit,emergency-stop actuator and main switch.The special starting method (asymmetricaltrigger control) for the soft starter functionprevents DC components that normallyoccur with a two-phase controlled starter.This guarantees a smooth motor startup.Ramp times and start voltage can be setby means of potentiometers. Suddenpressure fluctuations in the circulation of therefrigerant are thus prevented and protect allcomponents in the cooling circuit. To adjustthe refrigeration output to requirements, thesecond compressor is controlled via a DV6vector frequency inverter according to thespeed. This ensures optimum smooth runningcharacteristics for the motor and is ideallysuited to highly dynamic drives.With more than 200 percentstarting torque and virtuallyfull standstill torque, the DV6is one of the most powerfulvector frequency invertersin its class. Extensiveprotective functionsensure safe operation aswell as the protection offrequency inverter andmotor from overload,overtemperature,overvoltage and undervoltage aswell as phase loss.easy controlledThe refrigeration system is controlled byeasyControl (EC4P). This compact PLC withthe easy design combines the well-triedand simple easy concept with the benefitsof programming to IEC/ EN 61131-3.Furthermore, the CoDeSys programmingsystem and its functionality go far beyondthe standard requirements of EN 61131-3.The freely-graphical CFC (ContinuousFunction Chart) offers an additionalprogramming language. Options forsimulating the user program, the integratedfieldbus configurator, the powerful testand commissioning functions, as well as theintegrated visualization tool ensure thatapplication requirements can be implementedrapidly and simply.The EC4P comes with a 256 KB programmemory and 224 KB for data as well as 12digital and 8 transistor or 6 relay outputs.The combination of the EC4P PLC and theremote MFD-Titan display (IP65) mountedin the control cabinet door allow fastand simple visualization and operationof the refrigeration system, even in harshambient conditions, such as in dirty orhumid environments. Information such asthe operating mode of the system, alarmmessages and actual temperatures aredisplayed in plain text. The keypad of thedisplay allows the operating parameters tobe set according to the refrigeration systemto be controlled. All basic visualizationfunctions can be programmed easily usingthe function blocks of easySoft-CoDeSys.The communication connection is set upautomatically and therefore requires noadditional effort. And unlike foodstuffs,the easyControl stays fresh over a widetemperature range from -25 to +55 °C.A PID controller ensures constant climatic conditionseven when disturbance factors are present.The multi-function display visualizes all relevantoperating data.Quicklink ID:MS1812CONCLUSIONSepp Hersche, responsible for the systemconcept and the programming of therefrigeration control at Frigel explains:“We are impressed by the easyControland easySoft-CoDeSys automationsolution. Our service technicians setthe parameters individually via theMFD-Titan multi-function display andadapt it to suit the system at hand.In this way we can now control alltypes of refrigeration systems with asingle standard program. This savesus considerable work in programmingand maintaining the software. Ourrefrigeration system must be designedwith a high degree of reliability. Toensure this we also use Moeller productsfor the switching devices.”For Moeller Electric Sales and Support call KMparts.com (866) 595-961615