INVERTER SCHOOL TEXT INVERTER BEGINNER COURSE
INVERTER SCHOOL TEXTINVERTER BEGINNER COURSEINVERTER SCHOOL TEXTINVERTER BEGINNER COURSEMODELMODELCODEHEAD OFFICE : TOKYO BUILDING, 2-7-3 MARUNOUCHI, CHIYODA-KU, TOKYO 100-8310, JAPANNAGOYA WORKS : 1-14 , YADA-MINAMI 5-CHOME , HIGASHI-KU, NAGOYA , JAPANWhen exported from Japan, this manual does not require application to theMinistry of Economy, Trade and Industry for service transaction permission.Specifications subject to change without notice.
SAFETY PRECAUTIONS(Always read these instructions before the exercise.)When designing a system, always read the relevant manuals and give sufficient consideration tosafety.During the exercise, pay full attention to the following points and handle the equipments correctly.[Precautions for Exercise]！WARNING Do not touch the terminals while the power is on, to prevent an electric shock. When opening the safety cover, turn the power off or conduct a sufficient check of safety beforeoperation.！CAUTION Follow the instructor’s directions during the exercise. Do not remove the units of a demonstration machine or change wirings without permission.Doing so may cause a failure, malfunction, injury and/or fire. Turn the power off before installing or removing a unit.Failure to do so may result in a malfunction of the unit or an electric shock. When an error occurs, notify the instructor immediately.
IntroductionThank you very much for joining the FATEC school today. Also, thank you very much for choosing theMitsubishi products.Before taking a course in this school, please read the following brief explanation on the contents andpurpose of this school.The targets of this “Inverter introduction course” are from those who have never used an inverter before tothose who have some experience of using an inverter but want to know the basic principle, etc. This courseespecially describes the techniques, motor-related and power circuit-related contents that are common toinverters in an understandable way. This course also gives a simple account of the contents that are good toknow for using an inverter including basic operations of an actual machine.For the requests to know more details or to use selection software, the other schools are also available.School nameInverter practice courseDescriptionExplains the inverter principle, the precautions for using aninverter, etc. in an understandable way. You can understandthe functions, performance, etc. of an inverter by using anactual machine.Period2 days
---------------- INDEX ----------------1 BASICS OF MOTOR . 1-11.1 Type of Motor . 1-11.1.1 Overview . 1-11.1.2 Classification of motor . 1-21.2 Principle of Motor Operation . 1-31.2.1 Overview . 1-31.2.2 Three-phase motor (induction type) . 1-41.2.3 IPM motor (synchronous type) . 1-41.3 Performance of Motor . 1-51.3.1 Heat-resistant classes and temperature rise . 1-51.3.2 Rated torque . 1-61.3.3 Relationship between motor speed and generated torque . 1-71.3.4 Slip. 1-81.4 Installation . 1-91.4.1 Installation environment. 1-91.4.2 Outer sheath form of motor. 1-101.4.3 Mechanical specifications of main motors . 1-111.4.4 Movement direction of motor load . 1-122. BASICS OF INVERTER . 2-12.1 Basic Configuration . 2-12.1.1 Inverter. 2-12.2 Principle of Converter Operation . 2-22.2.1 Method to create DC from AC (commercial) power supply . 2-22.2.2 Input current waveform when capacitor is used as load. 2-32.2.3 Inrush current control circuit . 2-32.2.4 Principle of smoothing circuit operation. 2-42.3 Principle of Inverter Operation . 2-52.3.1 Method to create AC from DC . 2-52.3.2 Method to change frequency. 2-62.3.3 Method to change voltage. 2-62.3.4 Three-phase AC . 2-72.3.5 Switch element . 2-72.3.6 V/F pattern . 2-82.4 Regenerative Brake . 2-92.5 Control . 2-102.5.1 Difference between general-purpose inverter and vector inverter . 2-10
2.5.2 Control method. 2-113. DEMONSTRATION MACHINE OPERATION . 3-13.1 Inverter (FR-A720) . 3-13.1.1 Representative connection wiring diagram. 3-13.1.2 Main parameter settings and setting method . 3-33.1.3 Operating method. 3-74. PRECAUTIONS . 4-14.1 Environment . 4-14.1.1 Power supply harmonics. 4-14.1.2 Leakage current . 4-34.1.3 Noise. 4-44.1.4 Compliance to standards . 4-64.2 Capacity Selection . 4-84.2.1 Before selecting a capacity . 4-84.2.2 Selecting a motor according to driving force. 4-84.2.3 Selecting the most suitable capacity in consideration of acceleration/deceleration . 4-94.2.4 Software for capacity selection using a personal computer . 4-134.2.5 Software for starting up an inverter . 4-174.3 Application Examples . 4-194.3.1 Inverter application examples . 4-194.3.2 Vector inverter application examples . 4-204.4 Maintenance and Inspection . 4-214.4.1 Motor. 4-214.4.2 Inverter. 4-224.5 Troubleshooting . 4-234.5.1 Alarm display. 4-234.5.2 Wiring precautions and others . 4-24APPENDICES. App-1Appendix 1. Glossary . App-1
1 BASICS OF MOTOR1.1 Type of Motor1.1.1 OverviewA motor is a device which converts the electrical energy to the rotating mechanical energy.Many motors are used for various industrial machines to home appliances or bicycle in dailyuse.The types of motors can be classified by the performance, usage environmental condition,applications, etc. These are shown below.The motor driven by the inverter is a mainly three-phase squirrel-cage motor, and the motordriven by the vector inverter is three-phase type motor with encoder which detects a positionand speed. In addition, there is an energy-saving drive high-efficiency magnetic motor (IPM)for further energy saving.Classificationby powersupply categoryClassification byprinciple ofoperationClassificationby structureDC motorDC (direct currenttype) servo motorWound-rotormotorInduction ooruseAC motor3-phasemotorSM(synchronoustype) servomotorSynchronoustype motorDeviation phasestrating motorCondenser motorRepulsion startingmotorDrip-proofprotection typeTotally-enclosed-fan typeIM (induction type)servo motorMotor for specificenvironment(outdoor, waterproof,corrosion-proof,explosion-proof, etc.)IPM motorStepping motorPole numberconversion motorLinear motorGeared motorSubmersible motorEddy current with jointCommutator motor1-1
1 BASICS OF MOTOR1.1.2 Classification of motorThe following table shows the values for when a motor is used in combination with acontroller which can adjust the speed of a motor.Rated outputMaximumVariable speedrangemotor speedrange(kW)(r/min)(with inverter)Motor typesPositioning sethree-phasemotor100(guide)of Availability1/1000 1/100 vailableWithoutNotavailable1Use the limitswitch.with encoderVector inverterdedicated motorIPM motorUse the limitswitch.* Available for FREQROL-A700 series.1-210
1 BASICS OF MOTOR1.2 Principle of Motor Operation1.2.1 OverviewCurrentForceMagnetic fluxThe principle of operation is same for allmotors regardless of the size, and a torqueis occurred according to the "Fleming’sleft-hand rule" by which the current isForce to a conductorCurrentapplied to a conductor in a magnetic fieldMagnetic fluxand a force acts to the conductor.CurrentFig. 1.1 Fleming’s left-hand ruleThe principle of induction motor operation is as below.If the magnet is moved in the A direction when not touched with the disk, the disk also turnsin the same direction.At the same time as the movement of magnet, the electromotive force is induced in the disk,and the eddy current (induced current) is applied. The relationship between the eddy currentinduced in the disk and the magnetic flux by the magnet (Fleming's left-hand rule) causes anelectromagnetic power, and the disk is turned in the arrow f direction.Magnetic fluxARotation directionof the magnetNPermanent magnetS1) This phenomenon that the disk turns was provedby an Italian called Arago and was named .Arago’s diskCopper diskEddy current iBMagnetic lineTorque direction fwhich works tothe diskFig. 1.2 Arago’s disk1-32) The eddy current i is generatedby the Fleming’s right-hand rule.3) The electromagnetic power isgenerated in the direction bythe Fleming’s left-hand rule,and the disk moves.
1 BASICS OF MOTOR1.2.2 Three-phase motor (induction type)The cross section view of the three-phase motorCylindricalstator core(induction type) is shown on the right.It consists of stator core, stator winding, gap andStator winding(3-phase coil)Cylindricalrotor corerotor core.The current is applied to the winding part, and therotating magnetic field is generated. This rotatingmagnetic field is equivalent of Fig. 1.2. For thisvector inverter dedicated motor used with thethree-phase motor, the method, in which theRotor groove(aluminum die-casting)Fig. 1.3 Cross section of 3-phase motor (induction type)current creating a magnetic field with the currentapplied to the stator winding (current for magneticfield) and the orthogonal current generating , is used. The control performanceequivalent to a direct-current machine is ensuredin principle. In addition, the vector inverterdedicated motor is widely used because of itsconstant torque control from low speed to highspeed and good response.1.2.3 IPM motor (synchronous type)The rotor of the IPM motor (synchronous type)has permanent magnets embedded, and thestator consists of the winding which applies theStatorwindingNSSNcurrent. The cross section view is shown in Fig.S1.4. The current according to the movement of theNrotor is applied to the stator winding.SNSNNSBy detecting the magnet position at a start, themagnetic flux of these rotor magnets and thePermanentmagnet (rotor)current applied to the stator winding are controlledat right angles to each other.Fig. 1.4 Cross section of PM motor1-4
1 BASICS OF MOTOR1.3 Performance of Motor1.3.1 Heat-resistant classes and temperature riseVarious insulants with high heat resistance are used for general-purpose motors due to thesignificant development of insulating materials to be used.Currently, the motors have four types of heat-resistant class, E, B, F and H, and eachmaximum permissible temperature is as shown in Table 1.1. The rise of temperatureseverely shortens the life of motor.It is necessary to set as (Ambient temperature Motor temperature rise limit) Maximumpermissible temperature.Motors are designed for the ambient temperature of 40 .For example, the motor temperature is designed to fit into the temperature rise limitstandardized in Table 1.1 when the motor is operated with the rated torque in the ratedvoltage of 50Hz.Table 1.1 Heat-resistant class, maximum permissible temperature and temperature rise limitHeat-resistant classMaximum permissibleTemperature rise ple In the case of E type40 (ambient temperature) 75K (motor temperature rise limit) 120155(maximum permissible temperature) 120* The temperature rise of insulants is measured in a resistance method.1-5
1 BASICS OF MOTOR1.3.2 Rated torqueThe values of guaranteed output limit and designated voltage, current (torque), motor speed,frequency, ambient temperature, etc. by the motor manufacturer are collectively called arating. These data are called rated output, rated current (rated torque), rated motor speedand so on. For the rating of output, there are constant rating, short-time rating and repeatrating (duty rating).The constant rating is a constant output which can output continuously for a long time.For the short-time rating, one hour rating, for instance, is a constant output whichcontinuously outputs only for one hour after a motor is cooled down.The repeat rating (duty operation) indicates the output at the load if the load changesperiodically.Motor rated output P [kW][NRated torque TM 9550m]Rated motor speed N [r/min](Formula 1.1)These values are indicated on the name plates of motors or in test reports.ExampleWhat is the rated torque of 3.7kW 4P rated motor speed 1730 [r/min]?3.7 [kW]Rated torque TM 9550 20.41730[r/min]1-6[Nm]
1 BASICS OF MOTOR1.3.3 Relationship between motor speed and generated torqueThe torque characteristics are shown in Fig. 1.5 and the current characteristics in Fig. 1.6when a three-phase squirrel-cage motor is directly started.After the motor speedpasses this point,the torque starts to reduce.Torque[N m]MaximumtorqueTmApprox. 2 to 3 timesof the rated torqueTorqueStarttorqueTsApprox. 2times of therated torqueBalancing point of load torqueand motor generated torqueTorque increase withrotation riseTorque required foroperating a machineRatedtorqueLoadtorqueTLMotor speed[r / min]Fig. 1.5 Relationship of motor speed and torqueArea to be a generatorCurrentCurrent decreasewith rotation riseCurrent[A]StartcurrentIsRatedcurrentILMotor currentat load torque TLNMotor speed[r / min]Synchronous motorspeed N0The motor turns at a balancing pointof the load torque and the motorgenerated torque.Fig. 1.6 Relationship of motor speed and current1-7Slip S3 to 5%
1 BASICS OF MOTORHere, the motor speed is determined by the relationship between the load torque TL and themotor generated torque according to the figure on the previous page, it can be expressedwith the following formula.120Frequency f (Hz)Motor speed (1 - S)[r/min](Formula 1.2)Pole number PDetermined by thespecification of the motor.This magnitude is calledSynchronous speed N0.Determined by the magnitude ofthe load (load torque).The control with an inverter is widely used in a method which changes this frequency f as acontrol of the motor speed.1.3.4 SlipThe motor speed becomes a speed mismatched with the synchronous speed when the loadis applied as shown in Fig. 1.5 and 1.6. The indicated degree of the gap with thesynchronous speed is called "Slip".The slip is derived by the following formula.Synchronous motor speed N0- Motor speed NSlip S (Formula 1.3)Motor speed N0At a start, the "slip" is 100% since the motor speed is 0.When operating in the rated torque, the "slip" is generally 3 to 5%.When the load torque increases, the motor speed slows down, the "slip" increases and themotor current also increases.In the case of the rotation linked with outside, the motor speed becomes faster than thesynchronous speed and the slip will be a minus value.1-8
1 BASICS OF MOTOR1.4 Installation1.4.1 Installation environmentThe motor driven with a general-purpose inverter is a general-purpose motor which does notgenerally operate a feedback control.On the contrary, the motor driven with a vector inverter requires the feedback control and hasa built-in encoder (sensor) behind the motor. For the encoder, a semiconductor and electroniccomponents are installed.In addition, there are restrictions in the motor such as the environment and the lives ofinternal winding insulating material, bearing material, grease material inside the bearing andso on. The following environmental conditions are mainly defined.EnvironmentGeneral-purpose inverter motor-20Vector inverter dedicated motorto 40-10to ction typemotorTotally-enclosed-fantype motorSquirrel-cage induction motorSquirrel-cage induction motor85% RH or lessNo dripping to begeneratedElevation95% RH or lessNo dripping to begeneratedSpecial1000mor lessabovesealevelTotally-enclosed-fan type motorStandard90% RH or lessNo dripping to be generatedThe installation height of a motor is 1000m orless above sea level. If the atmosphericalpressure is low, the heat dissipation gets worse.The motor temperature, insulation, grease life,etc. during the operation cannot be guaranteed ifthe elevation is over 1000m, a special dealing isrequired.WithoutOil mistCorrosive gasDust and dirtAmbianceWithoutIndoor, without direct sunlightflammable gas(excluding outdoor,totally-closed-fan motor)Restrictions of the vibration passed on to the motor during the operationXVibrationresistanceYBoth X and Y directions24.9m/S(0.5G) or lessThe motors are designed with reference to the above environmental conditions.1-9
1 BASICS OF MOTOR1.4.2 Outer sheath form of motorAn outer sheath form for motor must be selected according to the installation condition andenvironment. Selecting an inappropriate motor may cause a trouble or shorten the motor life.Although the outer sheath forms (protection forms) are commonly classified into theclassification by JIS, the motors expressed in the classification by the international standardIEC are recently manufactured as well. The classifications by JIS and IEC are as below.(2) Classification by IEC(1) Classification by JISSymbols for the protection types of motorsSymbols for the protection forms ofare indicated by putting the first and secondmotors are indicated by putting the first andreference numbers corresponding to thesecond reference numbers correspondingfollowing table after IP.to the following table after JP.Example) IP 6 5Example) JP 4 4Second reference numberSecond reference numberFirst reference numberFirst reference numberUpper: Classification by JISFirst reference number: Grade for the solid foreignmatter entrance protectionLower: Classification by IECare indicated.Nonprotected type0Unprotected3Half-protected type1Protection to avoidthe entrance of solidforeign matter of50mm or more suchas a hand24Protection to avoid theentrance of solidforeign matter ofdiameter 1.0mm ormore such as a cableor a flakeDust-proof type5Second reference number: Grade for the waterentrance related protectionProtection frompowder dust, noentrance of thepowder dust thatdisturbs a normaloperationUpper: Classification by JISLower: Classification by IECNonprotected typeRainproof typeUnprotectedProtection against thewater spray within therange of 60 from theperpendicular0Absolute dust-proofstructure, totallyfree from theentrance of powderdust6Totally-enclosed typeProtected typeProtection to avoidthe entrance of solidforeign matter ofdiameter 12mm ormore such as aone-yen coinProtection to avoid theentrance of solidforeign matter ofdiameter 2.5mm ormore such as an edgeof tool or a wire3Ocean wavesprotection typeProtection againststrong jet water asocean waves, nowater immersionwhich disturbs anormal operation64Drip-proof type2Protection againstthe dripping withinthe range of 15from theperpendicular7Protection against thesplash from all directionsJetproof type58Protection against thejet water from alldirections1 - 10Immersionprotection typeNo water immersionwhich disturbs anormal operationeven if submergedin 150mm to 1mUnderwater typeUnder waterProtection againstthe dripping thatvertically drops suchas condensed water1mSplash-proof type1are indicated.Usable in water,usable for a longtime below water
1 BASICS OF MOTOR1.4.3 Mechanical specifications of main motorsGenerally, for general-purpose inverters and vector inverter motors, leg installed type (withlegs) motors are used in relatively large numbers.The following shows the point for the main mechanical specifications of these motors.Leg installedtypeInstallationmethodLeg installed typeFlange installed typeFrame numberC(Frame number)Flange installedtypeOpen typeOpen rd typeCoolingmethodTotally-enclosedtypeSuitable for adverseenvironment withdust, dirt, humidity, etc.Separate-coolingtypeAdopted with largecapacity in a forcedcooling systemDirect connectiondrivingDirectTableconnectionMachineon other endBeltMachineon other endMotorMotorPowertransmissionGearBelt drivingMotor Directly connectedto a machineGear drivingSet at right angleSet at right angleParallelize the centerof shaftsParallelize the centerof shafts.Excitation open brakeMotor speedSafety brakeBrakeBrake installation position forthe inverter motorExcitation open brakeBrake currentCoasting timeSudden stop timeTotal braking timeNon-safety brakeWhen turning the brake power off separatelyExcitation brake1 - 11
1 BASICS OF MOTOR1.4.4 Movement direction of motor loadThere are many types of mechanical drive systems by motors, and they can be useddepending on the purpose (such as desired accuracy, positioning accuracy, travel distanceand details of machine operation at work). For classifying these drive system mechanicalsections and considering the relationship with the motor, the following indicates thecategories of the mechanical movement directions. "mm" is used for the linear motion as acommand unit, and an angle or the number of partitions is used for the rotational motion.Category of movement directionHorizontal directionVertical direction (ascent and descent)Moving tableChainBallscrewLinear motionBallscrewMotorPLGReduction gearMotorB CounterweightMost common drive pattern which is used for a table feed ofeach machine or a transfermachine with a ballscrew, rack &pinion, belt, etc.ReductionWgearElectromagnetic brakeDrive pattern which is used for alifting shaft of transfer machine or arobot up-and-down shaft. As shownin the figure, the counter weight for aload balance is often mounted, andthe motor with the electromagneticbrake is used for avoiding a slip downat a power failure.Rotational motionTiming beltMotorWorm wheelBevel wheelMotor(Example 1. Connection with gear) (Example 2. Connection with belt)Drive pattern which is used for a rotary shaft of the index table, etc.The motor speed of load shaft (table rotary shaft) is generally slow andoften used by being reduced the speed according to the teeth number ratioof a gear or pulley.Types of motor direction1 - 12
2. BASICS OF INVERTER2.1 Basic Configuration2.1.1 InverterThe basic configuration of an inverter is as ral-purpose squirrel-cage(induction) motorInverterSmoothing circuitIMControl circuitVRFrequencycommandThe inside of this frame isgenerally called inverter.Fig. 2.1 Basic configuration of inverterEach part of an inverter has the following function.ConverterCircuit to change the commercial power supply to the DCSmoothing circuitCircuit to smooth the pulsation included in the DCInverterCircuit to change the DC to the AC with variable frequencyControl circuitCircuit to mainly control the inverter part2-1
2. BASICS OF INVERTER2.2 Principle of Converter Operation2) Inrush current control circuitThe converter part consists of1) Converterthe following parts as Fig. 2.3 shows:D1D2D3RP NFB1) Converter2) Inrush current D43) Smoothing circuitD5D6N -Fig. 2.3 Converter part2.2.1 Method to create DC from AC (commercial) power supplyA converter is a device to create the DC from the AC power supply. See the basicprinciple with the single-phase AC as the simplest example.Fig. 2.5 shows the example of the method to convert the AC to the DC by utilizing aresistor for the load in place of a smoothing capacitor.Diodes are used for the elements. These diodes let the current flow or not flowdepending on the direction to which the voltage is applied as Fig. 2.4 shows. -- Not flowable (Non conducting)Flowable (Conducting)Fig. 2.4 DiodeThis diode nature allows the following: When the AC voltage is applied between A andB of the circuit shown in Fig. 2.5, the voltage is always applied to the load in thesame direction shown in Table 2.1.That is to say, the AC is converted to the DC.(To convert the AC to the DC is generally called rectification.)Table 2.1 Voltage applied to the loadABAC voltageLoadAC flowing directionVoltage applied to loadDirection of solid lineSamedirectionDirection of dotted lineFig. 2.5 Rectifying circuitEFig. 2.6 (Continuous waveforms of the ones in Table 2.1)2-21
2. BASICS OF INVERTERFor the three-phase AC input, combining six diodesto rectify all the waves of the AC power supplyallows the output voltage as shown in Fig. 2.7.R phase S phase T phaseInput voltage V(3-phase)Converter partoutput voltage E12 VFig. 2.7 Converter part waveform2.2.2 Input current waveform when capacitor is used as loadThe principle of rectification is explained with a resistor. However, a smoothing capacitor is actually used for the load. If a smoothing capacitor is used, the input currentwaveforms become not sine waveforms but distorted waveforms shown in Fig. 2.8since the AC voltage flows only when it surpasses the DC voltage.ConverterE2VD1VoltageD2IAC powersupply VCurrent ctionD4Principle of converter2.2.3 Inrush current control circuitThe principle of rectification is explained with a resistor. However, a smoothingcapacitor is actually used for the load. A capacitor has a nature to store electricity.At the moment when the voltage is applied, a large inrush current flows for charginga capacitor.To prevent rectifying diodes from
Inverter practice course Explains the inverter principle, the precautions for using an inverter, etc. in an understandable way. You can understand the functions, performance, etc. of an
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Switches the inverter ON or OFF, resets the inverter 5.2 Inverter Status LED's 5.2.1 Inverter Switched Off 5.2.2 Inverter Switched ON 5.2.3 Overload "STATUS LED" Blinking indicates that the inverter is switched off. "STATUS LED" steady ON and the other LEDS rotating in a clockwise direction indicates that the inverter is switched on a
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LK/LW Series Power Star inverters Ensure that the inverter is switched off during the installation. It is recommended that you always connect the inverter to the battery bank first, as the battery power ultimately starts the inverter. If the inverter is connected to the AC input only, with the batteries disconnected or too low, the inverter .
PV Grid Tie Inverter Installation and Operation Manual Solis 4G Single Phase Inverter Ver 1.0-US version Solis-1P6K-4G-US, Solis-1P7K-4G-US, Solis-1P7.6K-4G-US, . To startup the inverter, the Grid Supply Main Switch (AC) must be switched on, before the solar panel's DC isolator shall be switched on. To stop the inverter, the Grid Supply
Article 505. Class I, Zone 0, 1, and 2 Locations Figure 500–2. Mike Holt Enterprises, Inc. www.MikeHolt.com 888.NEC.CODE (632.2633) 25 Hazardous (Classified) Locations 500.4 500.4 General (A) Classification Documentation. All hazardous (classified) locations must be properly documented. The documentation must be available to those who are authorized to design, install, inspect .
