MicroMaster 6SE92 - ECT Sales & Service

MICROMASTERMICROMASTER VectorMIDIMASTER VectorStandard Applications4.4 Energy Saving Variable Speed FanOperationA fan system with a mechanical variable flow device (such asa throttle valve) can be upgraded to an electronicallycontrolled system with great benefits in power saving andoperating noise.Clear TextDisplay(Cabinetmounted)CablebetweenOPM2anddriveMIDIMASTER Vector1234101167816179+10V0VAin 1+Ain1-Ain2+Ain2-5 Din1Din2Din3Din4Din5Din6+15VDout1 NCDout1 NODout1 ComDout2 NODout2 comAout+Aout-RS485PRS485NPTC1PTC21819202122121324251415U,V,W Output phasesand earth to motorMotorFanNote that the Clear Text Display module is included free ofcharge with each MIDIMASTER Vector.In the example shown, a MIDIMASTER Vector is used tocontrol the speed of a ventilation fan. The drive is configuredwith a quadratic torque control curve, so that at speedsbelow the 50Hz nominal speed the power consumption isvastly reduced as the motor current reduces quadratically inrelation to the output frequency.If resonances are experienced in the system these can besuppressed by using the skip frequency bands P014, P027,P028 and P029.Due to the IP21 protection rating of the drive, it is mounted ina cabinet and operated by the Clear Text Display which ismounted in the cabinet door and connected to theMIDIMASTER Vector with a cable. As well as switching thefan on and off the speed may be varied by using the ClearText Display panel. This is achieved by pressing the UpArrow key to increase the speed and the Down Arrow key todecrease the speed.This is known as the motorised potentiometer function. Thedrive is configured so that the speed settings made with thekeys are memorised even after a power fail. A furtherrefinement is the flying start function which allows the driveto synchronise itself to the fan even if the fan is alreadyturning (e.g. following a power break or fault condition). Thereverse key on the display is disabled to prevent inadvertentdamage to the fan. All required information such as speed,current and drive status is on the display.Siemens DA 64 – 1998/99 (04/99) 4/7