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    1Table of ContentsIntroduction ............................................................................. 2Totally Integrated Automation and DC Drives ......................... 4Mechanical Basics ................................................................... 6DC Motors .....................

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    2IntroductionWelcome to another course in the STEP 2000 series,Siemens Technical Education Program, designed to prepare ourdistributors to sell Siemens Energy & Automation productsmore effectively. This course covers Basics of DC Drives andrelated products.Upon completion of Basics of DC Driv...

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    3This knowledge will help you better understand customerapplications. In addition, you will be better able to describeproducts to customers and determine important differencesbetween products.If you are an employee of a Siemens Energy & Automationauthorized distributor, fill out the final exa...

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    4Totally Integrated Automationand DC DrivesTotally IntegratedTotally Integrated Automation (TIA) is a strategy developedAutomationby Siemens that emphasizes the seamless integration ofautomation products. The TIA strategy incorporates a widevariety of automation products such as programmablecont...

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    5Siemens DC DrivesSIMOREG® is the trade name for Siemens adjustable speedDC Drives. SIMOREG stands for SIemens MOtor REGulator.Siemens DC drives are an important element of the TIAstrategy. DC motors were the first practical device to convertelectrical energy into mechanical energy. DC motors, c...

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    6Mechanical BasicsBefore discussing Siemens DC drives it is necessary tounderstand some of the basic terminology associated with themechanics of DC drive operation. Many of these terms arefamiliar to us in some other context. Later in the course we willsee how these terms apply to DC drives.Force...

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    7If 10 lb of force were applied equally in both directions, the netforce would be zero and the object would not move.TorqueTorque is a twisting or turning force that tends to cause anobject to rotate. A force applied to the end of a lever, forexample, causes a turning effect or torque at the pivo...

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    8SpeedAn object in motion travels a given distance in a given time.Speed is the ratio of the distance traveled to the time it takesto travel the distance.Linear SpeedThe linear speed of an object is a measure of how long it takesthe object to get from point A to point B. Linear speed isusually gi...

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    9 Law of InertiaMechanical systems are subject to the law of inertia. The law ofinertia states that an object will tend to remain in its currentstate of rest or motion unless acted upon by an external force.This property of resistance to acceleration/deceleration isreferred to as the moment of in...

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    10WorkWhenever a force of any kind causes motion, work isaccomplished. For example, work is accomplished when anobject on a conveyor is moved from one point to another.Work is defined by the product of the net force (F) applied andthe distance (d) moved. If twice the force is applied, twice thewo...

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    11HorsepowerPower can be expressed in foot-pounds per second, but isoften expressed in horsepower (HP). This unit was defined inthe 18th century by James Watt. Watt sold steam enginesand was asked how many horses one steam engine wouldreplace. He had horses walk around a wheel that would lift awe...

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    12Review 11.____________ is the trade name for Siemens motorgenerators (DC drives).2.If 20 lb of force where applied in one direction and 5 lbof force applied in the opposite direction, the net forcewould be ____________ lb.3.If 5 lb of force were applied to a radius of 3 feet, thetorque would be...

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    13DC MotorsDC motors have been used in industrial applications for years.Coupled with a DC drive, DC motors provide very precisecontrol. DC motors can be used with conveyors, elevators,extruders, marine applications, material handling, paper,plastics, rubber, steel, and textile applications to na...

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    14ConstructionDC motors are made up of several major components whichinclude the following:•Frame•Shaft•Bearings•Main Field Windings (Stator)•Armature (Rotor)•Commutator•Brush AssemblyOf these components, it is important to understand theelectrical characteristics of the main field ...

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    15Basic ConstructionThe relationship of the electrical components of a DC motor isshown in the following illustration. Field windings are mountedon pole pieces to form electromagnets. In smaller DC motorsthe field may be a permanent magnet. However, in larger DCfields the field is typically an el...

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    16BrushesBrushes ride on the side of the commutator to provide supplyvoltage to the motor. The DC motor is mechanically complexwhich can cause problems for them in certain adverseenvironments. Dirt on the commutator, for example, can inhibitsupply voltage from reaching the armature. A certain am...

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    17Basic DC Motor OperationMagnetic FieldsYou will recall from the previous section that there are twoelectrical elements of a DC motor, the field windings and thearmature. The armature windings are made up of currentcarrying conductors that terminate at a commutator. DCvoltage is applied to the a...

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    18Magnetic FieldsA DC motor rotates as a result of two magnetic fieldsinteracting with each other. The first field is the main field thatexists in the stator windings. The second field exists in thearmature. Whenever current flows through a conductor amagnetic field is generated around the conduc...

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    19CEMFWhenever a conductor cuts through lines of flux a voltage isinduced in the conductor. In a DC motor the armatureconductors cut through the lines of flux of the main field. Thevoltage induced into the armature conductors is always inopposition to the applied DC voltage. Since the voltage ind...

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    20CommutationIn the following illustration of a DC motor only one armatureconductor is shown. Half of the conductor has been shadedblack, the other half white. The conductor is connected to twosegments of the commutator.In position 1 the black half of the conductor is in contact withthe negative ...

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    21As the conductor continues to rotate from position 2 toposition 3 current flows away from the commutator in thewhite half and toward the commutator in the black half.Current has reversed direction in the conductor. This isknown as commutation.

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    22Types of DC MotorsThe field of DC motors can be a permanent magnet, orelectromagnets connected in series, shunt, or compound.Permanent Magnet MotorsThe permanent magnet motor uses a magnet to supply fieldflux. Permanent magnet DC motors have excellent startingtorque capability with good speed r...

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    23Shunt MotorsIn a shunt motor the field is connected in parallel (shunt) withthe armature windings. The shunt-connected motor offers goodspeed regulation. The field winding can be separately excited orconnected to the same source as the armature. An advantageto a separately excited shunt field i...

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    24Speed/Torque CurvesThe following chart compares speed/torque characteristics ofDC motors.At the point of equilibrium, the torque produced by the motor isequal to the amount of torque required to turn the load at aconstant speed. At lower speeds, such as might happen whenload is added, motor tor...

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    25Review 21.The field in larger DC motors is typically an____________ .2.Whenever ____________ flows through a conductor amagnetic field is generated around the conductor.3.Voltage induced into the conductors of an armaturethat is in opposition to the applied voltage is known as____________ .4.Id...

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    26DC Motor RatingsThe nameplate of a DC motor provides important informationnecessary for correctly applying a DC motor with a DC drive.The following specifications are generally indicated on thenameplate:•Manufacturer’s Type and Frame Designation•Horsepower at Base Speed•Maximum Ambient ...

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    27HPHorsepower is a unit of power, which is an indication of therate at which work is done. The horsepower rating of a motorrefers to the horsepower at base speed. It can be seen fromthe following formula that a decrease in speed (RPM) results ina proportional decrease in horsepower (HP).Armature...

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    28WindingThe type of field winding is also listed on the nameplate. Shuntwinding is typically used on DC Drives.Field Volts and AmpsShunt fields are typically wound for 150 VDC or 300 VDC. Oursample motor has a winding that can be connected to either150 VDC or 300 VDC.Field EconomizingIn many app...

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    29Insulation ClassThe National Electrical Manufacturers Association (NEMA) hasestablished insulation classes to meet motor temperaturerequirements found in different operating environments. Theinsulation classes are A, B, F, and H.Before a motor is started the windings are at the temperatureof th...

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    30Speed/Torque Relationships of ShuntConnected MotorsAn understanding of certain relationships within a DC motorwill help us understand the purposes of various functions in aDC drive later in the course. The formulas given in the followingdiscussion apply to all three types of DC motors (series, ...

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    31Armature VoltageThe following armature voltage equation will be used todemonstrate various operating principles of a DC motor.Variations of this equation can be used to demonstrate howarmature voltage, CEMF, torque, and motor speed interact witheach other.Va = (KtΦn) + (IaRa)Where:Va = Applied...

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    32Motor TorqueThe interaction of the shunt and armature field flux producestorque (M). An increase in armature current (Ia) increasesarmature flux, thereby increasing torque. An increase in fieldcurrent (If) increases shunt field flux (Φ), thereby increasingtorque.M ≈ IaΦConstant TorqueBase s...

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    33Horsepower is said to be constant because speed (N) increasesand torque (M) decreases in proportion.Field SaturationIt can be seen from the speed (n) and torque (M) formulas thatfield flux (Φ) density has a direct effect on motor speed andavailable torque. An increase in field flux (Φ), for e...

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    34Review 31.One way to increase motor speed is to ____________armature voltage.a. increaseb. decrease2.CEMF is zero when the armature is ____________ .a. turning at low speedb. turning at max speedc. not turningd. accelerating3.A ____________ - connected motor is typically usedwith DC drives.4.A ...

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    35Basic DC DrivesThe remainder of this course will focus on applying theSIMOREG DC MASTER® 6RA70, to DC motors and associatedapplications. The SIMOREG DC MASTER 6RA70 drives aredesigned to provide precise DC motor speed control over awide range of machine parameters and load conditions.Selection...

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    36Siemens SIMOREG DC MASTER 6RA70 drives are available upto 1000 HP at 500 VDC in standard model drives. In addition,drives can be paralleled, extending the range up to 6000 HP.Siemens SIMOREG drives have a wide range ofmicroprocessor-controlled internal parameters to control DCmotor operation. I...

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    37Power ModulesThe SIMOREG 6RA70 is available in a power module and basedrive panels. The power module contains the control electronicsand power components necessary to control drive operationand the associated DC motor.Base Drive PanelsThe base drive panel consists of the power module mountedon ...

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    38High Horsepower DesignsHigh horsepower designs are also available with ratings up to14,000 amps. These drives have input ratings up to 700 VACand can operate motors with armature ratings up to 750 VDC.For additional information on high horsepower designSIMOREG 6RA70 DC MASTER drives, contact yo...

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    39Converting AC to DCThyristorA primary function of a DC drive, such as the SIMOREG 6RA70DC MASTER, is to convert AC voltage into a variable DCvoltage. It is necessary to vary to DC voltage in order to controlthe speed of a DC motor. A thyristor is one type of devicecommonly used to convert AC to...

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    40The thyristor will switch off when the anode is no longerpositive with respect to the cathode.AC to DC ConversionThe thyristor provides a convenient method of converting ACvoltage to a variable DC voltage for use in controlling the speedof a DC motor. In this example the gate is momentarily app...

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    41Volts RMSααααCosineFormulaVDC460 VAC01.00VDC = 460 x 1.35 x 1621460 VAC300.87VDC = 460 x 1.35 x 0.87538460 VAC600.50VDC = 460 x 1.35 x 0.50310.5460 VAC900.00VDC = 460 x 1.35 x 00460 VAC120-0.50VDC = 460 x 1.35 x (-0.50)-310.5460 VAC150-0.87VDC = 460 x 1.35 x (-0.87)-538460 VAC180-1.00VDC = ...

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    42The following illustration approximates the output waveform ofa fully controlled thyristor bridge rectifier for 0°, 60°, and 90°.The DC value is indicated by the heavy horizontal line. It isimportant to note that when thyristors are gated at 90° the DCvoltage is equal to zero. This is becau...

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    43Review 41.An increase of torque causes a corresponding____________ in horsepowera. increaseb. decrease2.Typically, DC motor armature voltage is either rated for____________ VDC or ____________ VDC.3.Identify the following insulation classes.4.The SIMOREG 6RA70 DC MASTER ____________ driveconsis...

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    44Basic Drive OperationControlling a DC MotorA thyristor bridge is a technique commonly used to control thespeed of a DC motor by varying the DC voltage. Examples ofhow a DC rectifier bridge operates are given on the next fewpages. Voltage values given in these examples are used forexplanation on...

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    45Basic OperationA DC drive supplies voltage to the motor to operate at adesired speed. The motor draws current from this powersource in proportion to the torque (load) applied to the motorshaft.100% Speed, 0% LoadIn this example an unloaded motor connected to a DC drive isbeing operated at 100%...

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    46100% Speed, 100% LoadA fully loaded motor requires 100% of rated armature currentat 100% speed. Current flowing through the armature circuitwill cause a voltage drop across the armature resistance (Ra).Full voltage (500 VDC) must be applied to a fully loaded motorto operate at 100% speed. To ac...

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    471 Quad, 4 QuadUp to this point we have only looked at a drive in single-quadrant operation. A single-quadrant DC drive will have sixthyristors.In the speed-torque chart there are four quadrants of operationaccording to direction of rotation and direction of torque. Afour-quadrant DC drive will ...

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    48Changing Direction ofThere are two ways to change the direction a DC motora DC Motorrotates.1. Reverse Armature Polarity2. Reverse Field PolarityReversing in Single-Field contactor reverse kits can be used to provide bidirectionalQuadrant Operationrotation from a single-quadrant drive. To turn ...

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    49Dynamic BrakingDynamic braking is often used on single quadrant drives as ameans of stopping a motor quickly. Dynamic braking is notrecommended for continuous or repetitive operation. Dynamicbraking kits for use with Siemens SIMOREG® drives aretypically designed to stop a load operating at bas...

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    50Four-Quadrant OperationThe dynamics of certain loads require four-quadrant operation.If motor voltage is suddenly reduced, negative torque isdeveloped in the motor due to the inertia of the connectedload. The motor acts like a generator by converting mechanicalpower from the shaft into electric...

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    51MotoringThe motor receives power from the incoming line. In thisexample the motor is operating at full speed (500 VDC).100% Speed, -100% LoadWhen the motor is required to stop quickly, the motoring bridgeshuts off and the regen bridge turns on. Due to the initial inertiaof the connected load th...

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    52Regen vs. Dynamic BrakingRegen and dynamic braking provide the same amount ofbraking power to slow a motor from maximum speed in fieldweakening to base speed. This is because field strengthincreases until the motor reaches base speed. However, frombase speed to stop, regen is capable of slowing...

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    53Review 51.When torque is developed in the forward direction andthe armature is turning in the forward direction, themotor is operating in quadrant ____________ .2.When the armature is turning in the forward directionbut torque is developed in the reverse direction, themotor is operating in quad...

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    54SIMOREG 6RA70 DC MASTER ElectronicsUp to this point we have looked at the power components of aDC Drive necessary to control the speed of a DC motor. Theactual control of these components is accomplished withelectronic hardware and technology software.Speed Control withSpeed control is one mode...

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    55Speed Control withA tachometer can be used when a more accurateTach Feedbackmeasurement of speed is needed, or when the motor will beoperated above base speed. A measurement of actual speed isreturned to the speed controller. The speed controller will makearmature voltage adjustments to maintai...

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    56Current MeasurementThe drive monitors current, which is summed with the speedcontrol signal at the current controller. The drive acts tomaintain current at or below rated current by reducing armaturevoltage if necessary. This results in a corresponding reduction inspeed until the cause of the o...

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    57Tuning the DriveA feature of the SIMOREG 6RA70 DC MASTER is the ability toself tune for a given motor and associated load. An improperlytuned control may result in an excessive speed overshootwhen changing from one speed to another. Oscillations canoccur which contribute to system instability.A...

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    58CUD1 BoardThe CUD1 board is the main control board for the SIMOREG6RA70. This board contains the necessary software andhardware interfaces for operating the drive in speed or torquecontrol. It has input and output connections for wiring thecontrol devices of various functions such as start/sto...

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    59Typical ConnectionsThe following diagram shows a typical connection used tooperate the drive. A normally open (NO) contact is used to startand stop the drive.Alternately, pushbuttons can be used to start and stop thedrive.

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    60Programming andSIMOREG 6RA70 drives can be programmed and operatedOperating Sourcesfrom various sources, such as the PMU, OP1S, or otherSIMATIC® HMI device such as the TP170A, TP170B, OP27, orMP370. In addition to these, various methods of serialcommunication is available through RS232 or RS48...

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    61CUD2 Expansion BoardThe CUD2 is typically selected when additional inputs andoutputs (I/O) are required. CUD2 I/O is selectable. Anadvantage to the CUD2 expansion board is that it mountsdirectly on the CUD1 and requires no additional hardware. TheCUD2 provides four optically isolated binary inp...

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    62EB1 and EB2EB1 and EB2 are half-sized expansion boards that provide aExpansion Boardsnumber of additional I/O possibilities. EB1 has three binaryinputs and four bidirectional binary I/O. Bidirectional I/O can beconfigured as a binary input or output. One of the analog inputsis used as a voltage...

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    63CommunicationsOne of the strong points of the SIMOREG 6RA70 is its serialinterface capabilities, which makes it easy to integrate thedrive with other automation components. Communicationoptions are available for PROFIBUS-DP, SIMOLINK®, CAN, andDeviceNet communications.SLBThe SLB communication ...

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    64CBCISO is a federation of standards organizations from over 100countries that develops voluntary standards for business,science, and technology. The official name is OrganizationInternationale de Normalisation, also known in the UnitedStates as the International Organization for Standardization...

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    65CBDThe CBD communication board is used to communicate withDeviceNet. DeviceNet is another communication protocol thatwas developed based on the CAN technology. DeviceNetprovides a low-level network for DeviceNet enabled devicessuch as sensors, motor starters, and drives to communicatewith highe...

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    66Electronics BoxThe electronics box contains the CUD1 board (main controlboard) and option boards. The CUD1 board is plugged intoslot 1.Mounting Option BoardsThere are several option boards available, which will bediscussed later in this section. Option boards are automaticallyrecognized by the ...

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    67There are a few rules that must be followed when mountingoption boards:•Option boards may be plugged into positions 2 or 3,however, position 2 must be filled first.•When used, a technology board (T400) is always installedin position 2.•If a communication board (CBP2, CBC. or CBD) is usedw...

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    68Review 61.____________ is the designation of the main electroniccontrol board in the SIMOREG 6RA70 DC MASTER.2.A ____________ ____________ ____________ isrequired when mounting option boards in the electron-ics box.3.Position ____________ must be filled first wheninstalling option boards.4.__...

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    69Parameters and Function BlocksThe SIMOREG 6RA70 DC MASTER features an extensiveparameter set that can easily be adapted to almost any drivetask, from simple to complex. A wide scope of parametersinclude:•Acceleration/Deceleration Control•Automatic Restart Function•Field Reversal•Various...

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    70Function ParametersAcceleration or deceleration times are examples of functionparameters. A feature of DC drives is the ability to increase ordecrease the armature voltage gradually. This accelerates anddecelerates the motor smoothly with less stress on the motorand connected load.Parameters P3...

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    71Visualization ParametersVisualization parameters are used for visualizing internalquantities. These parameters are only displayed and cannot bechanged by the operator. Visualization parameters aredistinguished by a lower case “r”. Parameter r038, for example,displays the value of voltage ...

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    72Indexing and Data SetsIn many applications it may be desirable to configure theSIMOREG 6RA70 DC MASTER for variations in operation. Forexample, there may be a situation in an application where it isdesirable to have different acceleration times. Indexedparameters can have up to four different v...

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    73The PI-controller’s job is to make speed corrections quickly aminimal amount of overshoot and oscillation. Parameter P225(gain) and parameter P226 (time) are used to tune the PI-controller’s performance. The end result should be a fastresponse time with about a 43% initial overshoot. The ...

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    74Connectors and binectors are identified by a name and number.Connectors with 16 bit resolution are identified with a “K”.Connectors with 32 bit resolution are identified with a “KK”.Binectors are identified with a “B”.BICOBICO is the term used to describe the method of connectingfun...

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    75Engineering ToolsThere are several engineering tools available optionally. Thesetools aid in programming, operating, troubleshooting, andmanaging SIMOREG 6RA70 DC MASTER drives.SIMOVISSIMOVIS® can be used to aid start-up, setting and savingparameters, and as a diagnostic tool for troubleshooti...

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    76QuickStartQuickStart is another tool useful in setting up SIMOREG DCdrives. A feature of this tool is the ability to communicate withspecific drives in a network of drives. A Wizard driven menuleads operators through a simplified start-up procedure step-by-step.Drive ESDrive ES is used to inte...

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    77ApplicationsWhen applying a DC drive and motor to an application it isnecessary to know the horsepower, torque, and speedcharacteristics of the load. The following chart shows typicalcharacteristics of various loads.Loads generally fall into one of three categories:CategoryDescriptionConstant T...

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    78Application ExamplesThe Siemens SIMOREG 6RA70 DC MASTER drives aredesigned to handle the most challenging applications. Thefollowing examples are just some of applications the SIMOREGcan be used on.Winders/CoilersDC motors offer superior characteristics at low speed forwinder and coiler operati...

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    79Marine ApplicationsDC drives offer several advantages in marine applications.Compact sizing is one of the biggest advantages. DC drivesalso adapt well from generator supplies such as found in themarine industry.Crane/HoistDC offers several advantages in applications that operate at lowspeed, su...

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    80Mining/DrillingDC is often preferred in the high horsepower applicationsrequired in the mining and drilling industry. DC drives offeradvantages in size and cost. They are rugged, dependable, andproven in the industry.ExtrudingExtruding is a price competitive industry. DC offers economicalsoluti...

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    81Selecting a Siemens DC DriveThe following flow diagram, along with the selection charts,will help you select the right DC drive for your application.

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    82The following tables provide catalog numbers for SIMOREG DCdrives up to 1000 HP. For larger drives consult your Siemenssales representative.Power ModuleSingle Quad, Non-Regen240 VDC 500 VDC37.5156RA7018-6FS22-0Z+X017.515306RA7025-6FS22-0Z+X011530606RA7028-6FS22-0Z+X0125601006RA7031-6FS22-0Z+X0...

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    83Power ModuleFour Quad, RegenBase DriveSignle Quad, Non-RegenBase DriveFour Quad, Regen240 VDC 500 VDC37.5156RA7018-6FV62-0Z+X017.515306RA7025-6FV62-0Z+X011530606RA7028-6FV62-0Z+X0125601006RA7031-6FV62-0Z+X0140751406RA7075-6FV62-0Z+X01601252106RA7078-6FV62-0Z+X01751502556RA7082-6FV62-0Z+X0112525...

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    84Review 71.Parameters that can be read only are referred to as____________ parameters.2.A function block consists of several ____________grouped together to perform a specific task.3.____________ is the term used to describe the methodof connecting function blocks together.4.Winders are examples...

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    85Review AnswersReview 11) SIMOREG; 2) 15; 3) 15; 4) b. Dividing Distance by Time;5) force; 6) external force.Review 21) electromagnet; 2) current; 3) CEMF;4) a. Permanent Magnet, b. Compound, c. Shunt, d. Series.Review 31) a. increase; 2) c. not turning; 3) shunt; 4) b. torque; 5 flux.Review 41)...

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    86Final ExamThe final exam is intended to be a learning tool. The bookmay be used during the exam. A tear-out answer sheet isprovided. After completing the test, mail the answer sheet infor grading. A grade of 70% or better is passing. Uponsuccessful completion of the test a certificate will be i...

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    875.____________ is the voltage induced into an armatureconductor of a DC motor in opposition to appliedvoltage.a.Armature voltageb.Field voltagec.CEMFd.EMF6.____________ current refers to the minimum amountof current flowing from anode to cathode to keep athyristor turned on.a.Armature currentd....

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    8810.Which of the following is not an advantage of regenover dynamic braking?a.Regen brakes faster from max speed tobase speedb.Regen brakes faster from base speed to stopc.Regen is not limited to duty cycle and cool-down periodsd.Regen can develop torque at zero speed11.____________ tuning tunes...

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    8916.Hoisting gear is an example of a ____________ load.a.constant torqueb.variable torquec.constant horsepowerd.constant speed17.____________ is used to communicate withPROFIBUS-DP.a.CBCc.CBDb.CBP2d.SBP18.____________ is the term used to describe the methodof connecting function blocks together....

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    90Notes

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    91Notes

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    92Notes

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