Yaskawa DR2 User Manual

Series SGM/SGMP/DR2

USER'S MANUAL

AC Servomotors and Driver

SGM/SGMP Servomotors DR2 Servopack

YASKAWA

YA S K A WA

MANUAL NO. TSE-S800-17D

PREFACE

The rapid progress being made in today’s automation and information technologies is resulting in a growing need for even more-advanced motion control for future high-tech equipment. The end result is a need for devices that can provide more-precise and quicker motion at higher speeds. Servo control technology makes this possible. Launched by Yaskawa in 1993, the Σ Series consists of innovative AC Servos that were developed using leading-edge servo control technology.

This manual covers all products information on the Σ Series SGMj/DR2, which feature superior functions and performance. This manual was designed to provide comprehensible information for users who are about to use a servo for the first time as well as for users who already have experience in using servos. This manual enables users to understand what Σ-Series AC Servos are all about and how to design, install, operate, and maintain a servo system. Keep this manual in a convenient location and refer to it whenever necessary in operating and maintaining the servo system.

YASKAWA ELECTRIC CORPORATION

General Precautions

S Some drawings in thismanual are shownwith the protectivecover or shields removed,in order to

describe the detail with more clarity. Make sure all coversand shields are replacedbefore operating this product.

S Some drawings in this manual are shown as typical example and may differ from the shipped

product.

S This manual may be modified when necessary because of improvement of the product,modifica-

tion or changes in specifications. Such modification is made as a revision by renewing the manual No.

S To order a copy of this manual, if your copy has been damaged or lost, contact your YASKAWA

representative listed on the last page stating the manual No. on the front cover.

S YASKAWA is not responsible for accidents or damages due to any modification of the product

made by the user since that will void our guarantee.

NOTES FOR SAFE OPERATION

Read this manual thoroughly before installation, operation, maintenance or inspection of the AC Servo

Drives. In this manual, the NOTES FOR SAFE OPERATION are classified as “WARNING” or

“CAUTION”.

WARNING

Indicates apotentially hazardous situation which, ifnot avoided, couldresult in deathor serious personal inju-

ry.

CAUTION

Indicates a potentially hazardous situation which, if not avoided, may result in minor or moderate personal

injury and/or damage to the equipment.

In some instances, items described in

follow these important items.

CAUTION

may also result in a serious accident. In either case,

WARNING

(INSTALLATION)

S After voltage resistance test, wait at least five minutes before servicing the

product.

Failure to observe this warning may result in electric shock.

(WIRING)

S Grounding must be in accordance with the national code and consistent

with sound local practices.

Failure to observe this warning may lead to electric shock or fire.

(OPERATION)

S Never touch any rotating motor parts during operation.

Failure to observe this warning may result in personal injury.

(INSPECTION AND MAINTENANCE)

S Be sure to turn OFF power before inspection or maintenance.

Otherwise, electric shock may result.

S After turning OFF power, wait at least five minutes before servicing the

product.

Otherwise, residual electric charges may result in electric shock.

CAUTION

(RECEIVING)

S Use the specified combination of SERVOMOTOR and SERVOPACK.

Failure to observe this caution may lead to fire or failure.

(INSTALLATION)

S Never use the equipment where it may be exposed to splashes of water,

corrosive or flammable gases, or near flammable materials.

Failure to observe this caution may lead to electric shock or fire.

(WIRING)

S Do not connect three−phase power supply to output terminals

Failure to observe this caution may lead to personal injury or fire.

S Securely tighten screws on the power supply and motor output terminals.

Failure to observe this caution can result in a fire.

and

CAUTION

(OPERATION)

S To avoid inadvertent accidents, run the SERVOMOTOR only in test run

(without load).

Failure to observe this caution may result in personal injury.

S Before starting operation with a load connected, set up user constants

suitable for the machine.

Starting operation without setting up user constants may lead to overrun failure.

S Before starting operation with a load connected, make sure emergency-

stop procedures are in place.

Failure to observe this caution may result in personal injury.

S During operation, do not touch the heat sink.

Failure to observe this caution may result in burns.

(INSPECTION AND MAINTENANCE)

S Do not disassemble the SERVOMOTOR.

Failure to observe this caution may result in electric shock or personal injury.

S Never change wiring while power is ON.

Failure to observe this caution may result in electric shock or personal injury.

Manual Contents

This manual providesΣ-Series users with information on the following:

•

An overview of servo systems for first-time users.

•

Checking the product on delivery and basic applications of the servo.

•

Servo applications.

•

Selecting an appropriate servo for your needs and placing an order.

•

Inspection and maintenance.

Manual Structure

All chapters in this manual are classified into one or more of three areas according to their contents:A,B, andC. Refer to the applicable chapters for the information you require.

Chapters explaining how to select a servo: For users who wish to gain a basic understanding of

Series products or who need to select an appropriate servo.

Chapters explaining how to design a servo system: For users who are about to design, install, and operate aΣ-Series Servo Control System.

Chapters explaining maintenance: For users who are going to maintain and troubleshootΣ-Series products.

Chapter

CHAPTER 1 For First-time Users of AC Servos

CHAPTER 2 Basic Uses of Σ-series Products

CHAPTER 3 Applications of Σ-series Products

CHAPTER 4 Using the Digital Operator

CHAPTER 5 Servo Selection and Data Sheets

CHAPTER 6 Inspection, Maintenance, and Troubleshooting

CHAPTER 7 Measures to Satisfy the Requirements of

Title Page Area

...................... .........

Provides an overview of servos and theΣSeries

......................... .........

Describes steps to take when product is received, plus basic wiring and application methods.

....................... .........

Describes the effective usage ofΣ-Series features according to application.

.............................. ........

Describes operating procedures forΣ-Series servos, turning features ON and OFF, setting control constants, etc.

........................ ........

Describes selection methods forΣ-Series servos and peripherals and provides servo specifications.

Describes user maintenance and troubleshooting.

EMC Directive

Provides the measures to conform to the EMC Directive.

169

203

........... ........

387

415

A, B

B........................................ .........

vii

APPENDIXES

Differences between DR2 and DR1, SGDA and SGD Servopacks 423

Servo Adjustment 429

List of I/O Signals 445

List of User Constants 465

List of Alarm Displays 477

Relationship between Reference Forms and User Constants 481

Reviewing the Full-closed Loop Specifications 489

............................................ ........

....................................... ........

................................... ........

.................................... ........

.. ........

............... ........

A, B. C

B, C

A, B, C

B, C

INDEX

.............................................................. ........

497

A, B, C

viii

Basic Terms

Unless otherwise specified, the following definitions are used:

Servomotor:

Servopack: An amplifier (Trademark of Yaskawa servo amplifier “DR2 Servopack”)

Servodrive: A SGM/SGMP Servomotor and an amplifier (DR2 Servopack)

Servo system: A complete servo control system consisting of servodrive, host controller,

Visual Aids

The following aids are used to indicate certain types of information for easier reference.

TERMS

Speed/Torque

-Series SGM/SGMP Servomotor

and peripheral devices

Indicates references for additional information.

Technical terms placed in bold in the text are briefly explained in a “TERMS” section at the bottom of the page. The following kinds of technical terms are explained: Technical terms that need to be explained to users who are not very familiar with servo systems or electronic devices and technical terms specific toΣSeries Servos that need to be explained in descriptions of functions.

The text indicated by this icon is applicable only to Servopack in speed/torque control mode.

Positions

JUSP-OP02A-1

NOTE

The text indicated by this icon is applicable only to Servopack in position control mode.

The text indicated by this icon explains the operating procedure using hand-held type digital operator (Type: JUSP-OP02A-1).

AΣ-Series Servodrive alone cannot ensure the functionality and performance of the entire machine control system. It must be combined with an appropriate machine and host controller so that the entire control system works properly. Therefore, carefully read the instruction manuals for the machine to be used before attempting to operate the servodrive.

Yaskawa, 1996



All rights reserved. Nopart of this publication may be reproduced,stored ina retrievalsystem, or transmitted, in anyform, or by any means, mechanical, electronic, photocopying, recording, or otherwise, without the prior written permission of Yaskawa. No patent liabilityis assumedwith respectto the use of theinformation containedherein. Moreover, becauseYaskawa is constantly striving to improve its high-quality products, the information contained in this manual is subject to change without notice. Every precaution has been taken in the preparation of this manual. Nevertheless, Yaskawa assumes no responsibility for errors or omissions. Neither is any liability assumed for damages resulting from the use of the information contained in this publication.

CHAPTER 1 FOR FIRST-TIME USERS OF AC SERVOS 1...............

1.1 Basic Understanding of AC Servos 2..........................................

1.1.1 Servo Mechanisms 2................................................

1.1.2 Servo Configuration 5...............................................

1.1.3 Features of Σ-Series Servos 11.........................................

CHAPTER 2 BASIC USES OF Σ-SERIES PRODUCTS 15.................

2.1 Precautions 16.............................................................

2.1.1 Notes on Use 16....................................................

2.2 Installation 18.............................................................

2.2.1 Checking on Delivery 18..............................................

2.2.2 Installing the Servomotor 19...........................................

2.2.3 Installing the Servopack 22............................................

2.3 Connection and Wiring 25....................................................

2.3.1 Connecting to Peripheral Devices 25....................................

2.3.2 Main Circuit Wiring and Power ON Sequence 28..........................

2.3.3 Examples of Connecting I/O Signal Terminals 30..........................

2.4 Conducting a Test Run 37....................................................

2.4.1 Test Run in Two Steps 37.............................................

2.4.2 Step 1: Conducting a Test Run for Motor without Load 39...................

2.4.3 Step 2: Conducting a Test Run with the Motor Connected to the Machine 43.....

2.4.4 Supplementary Information on Test Run 45...............................

2.4.5 Minimum User Constants Required and Input Signals 47....................

CHAPTER 3 APPLICATIONS OF Σ-SERIES PRODUCTS 49..............

3.1 Setting User Constants According to Machine Characteristics 52.....................

3.1.1 Changing the Direction of Motor Rotation 52..............................

3.1.2 Setting the Overtravel Limit Function 54.................................

3.1.3 Restricting Torque 57................................................

3.2 Setting User Constants According to Host Controller 64............................

3.2.1 Inputting Speed Reference 64..........................................

3.2.2 Inputting Position Reference 69........................................

3.2.3 Using Encoder Output 76.............................................

3.2.4 Using Contact I/O Signals 80..........................................

3.2.5 Using Electronic Gear 82.............................................

3.2.6 Using Contact Input Speed Control 86...................................

3.2.7 Using Torque Control 91..............................................

3.2.8 Using Torque Feed-forward Function 97.................................

3.2.9 Using Torque Restriction by Analog Voltage Reference 98...................

3.2.10 Using the Reference Pulse Inhibit Function (INHIBIT) 100....................

3.2.11 Using the Reference Pulse Input Filter Selection Function 101.................

3.2.12 Using the Analog Monitor 102..........................................

3.3 Setting Up the Σ Servopack 103................................................

3.3.1 Setting User Constants 103.............................................

3.3.2 Setting the Jog Speed 104..............................................

3.3.3 Setting the Number of Encoder Pulses 105.................................

3.3.4 Setting the Motor Type 106.............................................

CONTENTS

3.4 Setting Stop Mode 107.......................................................

3.4.1 Adjusting Offset 107..................................................

3.4.2 Using Dynamic Brake 108.............................................

3.4.3 Using Zero-Clamp 109................................................

3.4.4 Using Holding Brake 110..............................................

3.5 Running the Motor Smoothly 114...............................................

3.5.1 Using the Soft Start Function 114........................................

3.5.2 Using the Smoothing Function 115.......................................

3.5.3 Adjusting Gain 115...................................................

3.5.4 Adjusting Offset 116..................................................

3.5.5 Setting the Torque Reference Filter Time Constant 116.......................

3.6 Minimizing Positioning Time 118...............................................

3.6.1 Using Autotuning Function 118.........................................

3.6.2 Setting Servo Gain 118................................................

3.6.3 Using Feed-forward Control 120.........................................

3.6.4 Using Proportional Control 120.........................................

3.6.5 Setting Speed Bias 121................................................

3.6.6 Using Mode Switch 122...............................................

3.7 Forming a Protective Sequence 128.............................................

3.7.1 Using Servo Alarm Output and Alarm Code Output 128......................

3.7.2 Using Servo ON Input Signal 132........................................

3.7.3 Using Positioning Complete Signal 133...................................

3.7.4 Using Speed Coincidence Output Signal 134...............................

3.7.5 Using Running Output Signal 136.......................................

3.7.6 Using Servo Ready Output Signal 138....................................

3.8 Special Wiring 140..........................................................

3.8.1 Wiring Instructions 140................................................

3.8.2 Wiring for Noise Control 142...........................................

3.8.3 Using More Than One Servo Drive 147...................................

3.8.4 Using Regenerative Units 148...........................................

3.8.5 Using an Absolute Encoder 151.........................................

3.8.6 Extending an Encoder Cable 159........................................

3.8.7 Using DR2 Servopack with High Voltage Line 161..........................

3.8.8 Connector Terminal Layouts 163........................................

CHAPTER 4 USING THE DIGITAL OPERATOR 169.....................

4.1 Basic Operations 170.........................................................

4.1.1 Connecting the Digital Operator 170.....................................

4.1.2 Resetting Servo Alarms 171............................................

4.1.3 Basic Functions and Mode Selection 172..................................

4.1.4 Operation in Status Display Mode 173....................................

4.1.5 Operation in User Constant Setting Mode 176..............................

4.1.6 Operation in Monitor Mode 179.........................................

xii

CONTENTS

4.2 Using the Functions 183......................................................

4.2.1 Operation in Alarm Trace-back Mode 183.................................

4.2.2 Operation Using the Digital Operator 186.................................

4.2.3 Autotuning 188......................................................

4.2.4 Reference Offset Automatic Adjustment 195...............................

4.2.5 Speed Reference Offset Manual Adjustment Mode 197.......................

4.2.6 Clearing Alarm Trace-back Data 200.....................................

4.2.7 Checking Motor Type 201..............................................

4.2.8 Checking Software Version 201.........................................

CHAPTER 5 SERVO SELECTION AND DATA SHEETS 203...............

5.1 Selecting a Σ-Series Servo 205.................................................

5.1.1 Selecting a Servomotor 205............................................

5.1.2 Selecting a Servopack 212.............................................

5.1.3 Digital Operator 216..................................................

5.2 SGM Servomotor 217........................................................

5.2.1 Ratings and Specifications 217..........................................

5.2.2 Mechanical Characteristics 230..........................................

5.3 Servopack Ratings and Specifications 233........................................

5.3.1 Ratings and Specifications 233..........................................

5.3.2 Power Consumption 238...............................................

5.3.3 Overload Characteristics 239...........................................

5.3.4 Starting Time and Stopping Time 240.....................................

5.3.5 Load Inertia 241.....................................................

5.3.6 Overhanging Loads 246...............................................

5.4 Σ-Series Dimensional Drawings 247.............................................

5.4.1 Servomotor Dimensional Drawings 247...................................

5.4.2 Servomotor Dimensional Drawings

5.4.3 Servopack Dimensional Drawings 329....................................

5.4.4 Digital Operator Dimensional Drawing 334................................

5.5 Selecting Peripheral Devices 335...............................................

5.5.1 Selecting Peripheral Devices 335........................................

5.5.2 Order List 341.......................................................

5.6 Specifications and Dimensional Drawings of Peripheral Devices 349...................

5.6.1 Cable Specifications and Peripheral Devices 349............................

5.6.2 Motor Cables 355....................................................

5.6.3 Connector Kits 358...................................................

5.6.4 Brake Power Supply 363...............................................

5.6.5 Encoder Cables 365...................................................

5.6.6 Battery for Absolute Encoder 371........................................

5.6.7 1CN Connector 371...................................................

5.6.8 Circuit Breaker 373...................................................

5.6.9 Noise Filter 374......................................................

5.6.10 Magnetic Contactor 375...............................................

5.6.11 Surge Suppressor 376.................................................

5.6.12 Regenerative Unit 376.................................................

5.6.13 Variable Resistor for Speed Setting 379...................................

(TÜV approved, conforming to the machine instructions) 289..................

xiii

CONTENTS

5.6.14 Encoder Signal Converter Unit 379......................................

5.6.15 Cables for Connecting PC and Servopack 381..............................

5.6.16 4CN Connector 385...................................................

CHAPTER 6 INSPECTION, MAINTENANCE, AND TROUBLESHOOTING 387.

6.1 Inspection and Maintenance 388................................................

6.1.1 Servomotor 388......................................................

6.1.2 Servopack 389.......................................................

6.1.3 Replacing Battery for Absolute Encoder 390...............................

6.2 Troubleshooting 391.........................................................

6.2.1 Troubleshooting Problems with Alarm Display 391..........................

6.2.2 Troubleshooting Problems with No Alarm Display 409.......................

6.2.3 Internal Connection Diagram and Instrument Connection Examples 411.........

CHAPTER 7 MEASURES TO SATISFY THE REQUIREMENTS OF

EMC DIRECTIVE 415.....................................

7.1 What is European Safe Standard? 416............................................

7.1.1 What is EN Standard? 416.............................................

7.1.2 What is CE Marking? 416..............................................

7.1.3 EMC Directive 417...................................................

7.1.4 Certification Body TÜV Authorized by EU 417.............................

7.2 Measures to Satisfy the Requirements of EMC Directive 418.........................

7.2.1 Applicable Servomotor 418.............................................

7.2.2 Applicable Noise Filter 418.............................................

7.2.3 Motor Cables 419....................................................

7.2.4 Encoder Cables 419...................................................

7.2.5 Control I/O 420......................................................

7.2.6 Digital Operator and Monitoring by Personal Computer 420...................

7.2.7 The Core on the Cable 421.............................................

7.2.8 Wiring 421..........................................................

APPENDIXES

A Differences Between DR2 and DR1, SGDA and SGD Servopacks 423..................

B Servo Adjustment 429........................................................

B.1 Σ-Series AC Servopack Gain Adjustment 430.....................................

B.1.1 Σ-Series AC Servopacks and Gain Adjustment Methods 430...................

B.1.2 Basic Rules for Gain Adjustment 431.....................................

B.2 Adjusting a Servopack for Speed Control 432.....................................

B.2.1 Adjusting Using Auto-tuning 432........................................

B.2.2 Manual Adjustment 433...............................................

B.3 Adjusting a Servopack for Position Control 436...................................

B.3.1 Adjusting Using Auto-tuning 436........................................

B.3.2 Manual Adjustment 437...............................................

B.4 Gain Setting References 441...................................................

B.4.1 Guidelines for Gain Settings According to Load Inertia Ratio 441..............

C List of I/O Signals 445........................................................

D List of User Constants 465.....................................................

xiv

CONTENTS

E List of Alarm Displays 477....................................................

F Relationship between Reference Forms and User Constants 481.......................

G Reviewing the Full-closed Loop Specifications 489.................................

INDEX 497...........................................................

FOR FIRST-TIME USERS OF AC SERVOS

This chapter is intended for first-time users of AC servos. It describes the basic configuration of a servo mechanism and basic technical terms relating to servos. Users who already have experience in using a servo should also take a look at this chapter to understand the features of Σ-Series AC Servos.

1.1 Basic Understanding of AC Servos 2...........

1.1.1 Servo Mechanisms 2.................................

1.1.2 Servo Configuration 5................................

1.1.3 Features of Σ-Series Servos 11..........................

FOR FIRST-TIME USERS OF AC SERVOS

1.1.1 Servo Mechanisms

1.1 Basic Understanding of AC Servos

This section describes thebasic configuration of a servo mechanismand technical terms relating to servos and also explains the features of Σ-Series AC Servos.

1.1.1 Servo Mechanisms 2..............................................

1.1.2 Servo Configuration 5..............................................

1.1.3 Features of Σ-Series Servos 11......................................

1.1.1 Servo Mechanisms

You may be familiar with the following terms:

• Servo

• Servo mechanism

• Servo control system

In fact, these terms are synonymous. They have the following meaning:

A control mechanism that monitors physical quantities such as specified positions.

In short, a servo mechanism is like a servant who does tasks faithfully and quickly according to his master’s instructions. In fact, “servo” originally derives from the word “servant.”

TERMS

Servo mechanism

According to Japanese Industrial Standard (JIS) terminology, a “servo mechanism” is defined as a mechanism that uses the position, direction, or orientation of an object as a process variable to control a system to follow any changes in a target value (set point). More simply, a servo mechanism is a control mechanism that monitors physical quantities such as specified positions. Feedback control is normally performed by a servo mechanism. (Source: JIS B0181)

1.1 Basic Understanding of AC Servos

Servo system could be defined in more detail as a mechanism that:

• Moves at a specified speed and

• Locates an object in a specified position

To develop such a servo system, an automatic control system involving feedback control must be designed. This automatic control system can be illustrated in the following block diagram:

Configuration of Servo System

Specified position

input

Servo amplifier

Servo motor

Feedback part

Detector

Controlled machine (load)

Machine position

output

This servo system is an automatic control system that detects the machine position (output data), feeds back the data to the input side, compares it with the specified position (input data), and moves the machine by the difference between the compared data.

In other words, the servo system is a system to control the output data to match the specified input data.

If, for example, the specified position changes, the servo system will reflect the changes.

In the above example, input data is defined as a position, but input data can be any physical quantities such as orientation (angle), water pressure, or voltage.

TERMS

Position, speed, force (torque), electric current, and so on are typical controlled values for a servo system.

The main technical terms used in this manual are as follows:

1) Servo mechanism

2) Servo

Normally, servo is synonymous with servo mechanism. However, because “mechanism” is omitted, the meaning becomes somewhat ambiguous. Servo may refer to the entire servo mechanism but may also refer to an integral part of a servo mechanism such as a servomotor or a servo amplifier. This manual also follows this convention in the use of the term “servo”.

Feedback control

A control that returns process variables to the input side and forms a closed loop. It is also called closed-loop control.

FOR FIRST-TIME USERS OF AC SERVOS

1.1.1 Servo Mechanisms cont.

3) Servo control system

Servo control system is almost synonymous with servo mechanism but places the focus on system control. In this manual, the term “servo system” is also used as a synonym of servo control system.

Related Terms Meaning

Servomotor General servomotors or Yaskawa SGM/SGMP

Servomotors. In some cases, a position detector (encoder) is included in a servomotor.

Servopack Trademark of Yaskawa servo amplifier “DR2 Servopack.”

Servo drive A Servomotor and amplifier pair. Also called “servo.”

Servo system A closed control system consisting of a host controller,

servo drive and controlled system to form a servo mechanism.

Host controller

Reference

Amplifier (Servopack)

Servo drive

Servomotor

Servo system

Operate

Controlled system

1.1.2 Servo Configuration

1) Configuration of Servo System

The following diagram illustrates a servo system in detail:

1.1 Basic Understanding of AC Servos

Host controller

(5)

Position or speed reference

Servo amplifier

Comparator

(Input)

Position or speed feedback

Power amplifier

Detector

(1) Controlled system: Mechanical system for which the position or speed is to be con-

trolled. This includes a drive system that transmits torque from a servomotor.

(4)

Motor drive circuit

Gear

(2)

(3)

Servomotor Drive system

(Output)

(1)

Controlled system

Position

Speed

Movable table

Ball screw

(2) Servomotor: A main actuator that moves a controlled system. Two types are

available: AC servomotor and DC servomotor.

(3) Detector: A position or speed detector. Normally, an encoder mounted on

a motor is used as a position detector.

(4) Servo amplifier: An amplifier that processes an error signal to correct the differ-

ence between a reference and feedback data and operates the servomotor accordingly. A servo amplifier consists of a comparator, which processes error signals, and a power amplifier, which operates the servomotor.

(5) Host controller: A device that controls a servo amplifier by specifying a position

or speed as a set point.

FOR FIRST-TIME USERS OF AC SERVOS

1.1.2 Servo Configuration cont.

Servo components (1) to (5) are outlined below:

(1) Controlled system

In the previous figure, the controlled system is a movable table for which the position or speed is controlled. The movable table is driven by a ball screw and is connected to the servomotor via gears. So, the drive system consists of:

Gears + Ball Screw

This drive system is most commonly used because the power transmission ratio (gear ratio) can be freely set to ensure high positioning accuracy. However, play in the gears must be minimized.

The following drive system is also possible when the controlled system is a movable table:

Coupling + Ball Screw

When the power transmission ratio is 1 : 1, a coupling is useful because it has no play.

Coupling

Rolling-contact guide

Ball screw

Rolling-contact bearing

This drive system is widely used for machining tools.

Housing

Timing Belt + Trapezoidal Screw Thread

A timing belt is a coupling device that allows the power transmission ratio to be set freely and that has no play.

A trapezoidal screw thread does not provide excellent positioning accuracy, so can be

Trapezoidal screw thread

treated as a minor coupling device.

Servomotor

Timing belt

To develop an excellent servo system, it is important to select a rigid drive system that has no play.

Configure the controlled system by using an appropriate drive system for the control purpose.

TERMS

Drive system

Also called a drive mechanism. A drive system connects an actuator (such as a servomotor) to a controlled system and serves as a mechanical control component that transmits torque to the controlled system, orientates the controlled system, and converts motion from rotation to linear motion and vice versa.

(2) Servomotor

(a) DC Servomotor and AC Servomotor

Servomotors are divided into two types: DC servomotors and AC servomotors.

DC servomotors are driven by direct current (DC). They have a long history. Up until the 1980s, the term “servomotor” used to imply a DC servomotor.

1.1 Basic Understanding of AC Servos

From 1984, ACservomotors were emerging as a result of rapid progress inmicroprocessor technology. Driven by alternating current (AC), AC servomotors are now widely used because of the following advantages:

• Easy maintenance: No brush

• High speed: No limitation in rectification rate

Note however that servomotors and Servopacks use some parts that are subject to mechanical wear or aging. For preventive maintenance, inspect and replace parts at regular intervals. For details, refer to Chapter 6 Inspection, Maintenance, and Troubleshooting.

(b) AC Servomotor

AC servomotors are divided into two types: synchronous type and induction type. The synchronous type is more commonly used.

For a synchronous type servomotor, motor speed is controlled by changing the frequency of alternating current.

A synchronous type servomotor provides strong holding torque whenstopped, so this type is ideal when precise positioning is required. Use this type for a servo mechanism for position control.

The following figure illustrates the structure of a synchronous type servomotor:

Rotary disc

Light-emitting element

Position detector (encoder)

Light-receiving element

Armature wire

Lead wire

Housing

Stator core

Magnet

Front cap

Ball bearing

Shaft

Rotor core

Yaskawa SGM and SGMP Servomotors are of the synchronous type.

FOR FIRST-TIME USERS OF AC SERVOS

1.1.2 Servo Configuration cont.

A servomotor must have “instantaneous power” so that it can start as soon as a start reference is received. The term “power rating (kW/s)” is used to represent instantaneous power. It refers to the electric power (kW) that a servomotor generates per second. The greater the power rating, the more powerful the servomotor.

(3) Detector

A servo system requires a position or speed detector. It uses an encoder mounted on a servomotor. Optical and magnetic detection methods are both available. Encoders are divided into the following two types:

(a) Incremental Encoder

An incremental encoder is a pulse generator, which generates a certain number of pulses per revolution (e.g., 2,000 pulses per revolution). If this encoder is connected to the mechanical system and one pulse is defined as a certain length (e.g., 0.001 mm), it can be used as a position detector. However, this encoder does not detect an absolute position and merely outputs a pulse train. Hence zero return operation must be performed before positioning. The following figure illustrates the operation principle of a pulse generator (Optical method):

Phase A pulse train

Phase B pulse train

Fixed slit

Light-receiving element

Rotary slit

Center of revolution

Phase A

Phase B

Phase Z

Rotary disc

Slit

Light-emitting element

(b) Absolute Encoder

An absolute encoder is designedto detect an absolute angle of rotation as well as to perform the general functions of an incremental encoder. With an absolute encoder, therefore, it is possible to create a system that does not require zero return operation at the beginning of each operation.

• Difference between an absolute An absolute

encoder will keep track of the motor shaft position even if system

and incremental encoder:

power is lost and some motion occurs during that period of time. The incremental encoder is incapable of the above.

1.1 Basic Understanding of AC Servos

(4) Servo amplifier

A servo amplifier is required to operate an AC servomotor.

The following figure illustrates the configuration of a servo amplifier:

Servo amplifier

Motor driving AC power

Servomotor

Commercial AC power

Reference input

Comparator

Feedback

Power amplifier

A servo amplifier consists of the following two sections:

(a) Comparator

A comparator consists of a comparison function and a control function. The comparison function compares reference input (position or speed) with a feedback signal and generates a differential signal.

TERMS

The control function amplifies and transforms the differential signal. In other words, it performs proportional (P) control or

proportional/integral (PI) control

(It is not important if you do not understand these control terms completely at this point.)

(b) Power Amplifier

A power amplifier runs the servomotor at a speed or torque proportional to the output of the comparator. In other words, from the commercial power supply of 50/60 Hz, it generates alternating current with a frequency proportional to the reference speed and runs the servomotor with this current.

Proportional/integral (PI) control

PI control provides more accurate position or speed control than proportional control, which is more commonly used.

FOR FIRST-TIME USERS OF AC SERVOS

1.1.2 Servo Configuration cont.

(5) Host Controller

A host controller controls a servo amplifier by specifying a position or speed as a set point.

For speed reference, a position control loop may be formed in the host controller when a position feedback signal is received. Yaskawa PROGIC-8 is a typical host controller.

TERMS

PROGIC-8

A programmable machine controller. If combined with a servo amplifier for speed control (maximum eight axis control), the PROGIC-8 can provide position control. The PROGIC-8 also provides programmable controller functions.

1.1.3 Features of Σ-Series Servos

1) Σ-Series SGM/SGMP Servomotors are synchronous type servomotors and have the following features:

• Size and weight reduced to one-third those of

our conventional models. Compact Servomotor for saving installation space.

• Servo performance (power rating) enhanced to

three times that of our conventional models. Enhanced power rating (kW/s) to satisfy every need.

• A wide product range covering rated output of

30 W to 750 W.

1.1 Basic Understanding of AC Servos

SGM type

Supply Voltage Rated Output 100 VAC: 30 W, 50 W, 100 W, 200 W, 300 W

(0.04 HP, 0.07 HP, 0.13 HP, 0.27 HP, 0.40 HP)

200 VAC: 30 W, 50 W, 100 W, 200 W, 400 W, 750 W

(0.04 HP, 0.07 HP, 0.13 HP, 0.27 HP, 0.53 HP, 1.01 HP)

2) DR2 Servopacks can perform speed/torque or position control. Select the control mode by setting of the user constant Cn-02 (memory switch).

• Speed/Torque Control Mode: User constant

Cn-02 (memory switch) Bit B = 0 This mode uses speed or torque reference input. Reference input is by analog voltage.

• Position Control Mode: User constant Cn-02

(memory switch) Bit B = 1 This mode uses position reference input. Reference

input is by pulse train.

SGMP type

DR2 Servopack

TERMS

Power rating (kW/s)

A constant that represents response performance of a servomotor. It can be determined by dividing squared rated torque by motor inertia. Power rating is the electric power (kW) that a servomotor can generate per second. The greater the power rating, the more powerful the servomotor.

FOR FIRST-TIME USERS OF AC SERVOS

1.1.3 Features ofΣ -Series Servos cont.

3) The most common usage of a speed/torque control Servopack is shown below:

• Using Servopack in Speed/Torque Control Mode (Speed Control)

Position feedback

Position reference +

Speed reference

(Analog voltage)

Position

Host controller

Position control loop

Servopack

(speed/torque control)

Speed

Convert

Pulse train

Position feedback

Power amplifier

Servomotor

Torque (current) feedback

Encoder

As shown in the figure above, a position control loop is formed in the host controller. The host controller compares a position reference with a position feedback signal and sends processing results to the Servopack as a speed reference.

In this way, the host controller can freely perform the control required for the servo mechanism. The Servopack undertakes the speed control loop and subsequent control processing.

Yaskawa programmable machine controller PROGIC-8 is available as a typical host controller.

1.1 Basic Understanding of AC Servos

4) Speed/torque control Servopack can also provide torque control as shown below.

• Using Servopack in Speed/Torque Control Mode (Torque Control)

Host controller

Position monitoring

Position information

Speed reference (Analog voltage)

Torque reference

(Analog voltage)

Position

Speed

Convert

Pulse train

Position feedback

Power amplifier

Servopack (speed/torque control)

Torque (current) feedback

Servomotor

Encoder

Set the user constants for Servopack to switch between the following torque control modes:

(1) Controlling servomotor torque by torque reference

(Torque control I)

(2) Operating servomotor by switching between torque reference and speed

reference

(Torque control II)

The host controller outputs a torque reference or speed reference to control the Servopack. It also receives a pulse train (position information) from the Servopack and uses itto monitor the position.

FOR FIRST-TIME USERS OF AC SERVOS

1.1.3 Features ofΣ -Series Servos cont.

5) Position control Servopack can be used as below.

• Using Servopack in Position Control Mode

Position reference

Position information

Pulse train

Host controller

Position monitoring

Speed/current loop

Pulse train

Position feedback

Servopack

(position control)

Power amplifier

Servomotor

Encoder

The host controller can send a position reference (pulse train) to the Servopack to perform positioning or interpolation. This type of Servopack contains a position control loop.

User constants can be used to select either of the following pulse trains:

(1) Code and pulse train

(2) Two-phase pulse train with 90° phase difference

(3) Forward and reverse pulse trains

The host controller receives a pulse train (position information) from the Servopack and uses it to monitor the position.

6) A Digital Operator can be used to set user constants for a Servopack as follows:

(1) Setting user constants to enable or disable each function

(2) Setting user constants required for functions to be used

Set user constants according to the servo system to be set up.

BASIC USES OF Σ-SERIES PRODUCTS

This chapter describes the first things to dowhenΣ-Series products aredelivered. It also explainsthe most fundamental ways of connecting andoperating

-Series products. Both first-time and experienced servo users

this chapter.

2.1 Precautions 16...............................

2.2 Installation 18...............................

2.1.1 Notes on Use 16.....................................

2.2.1 Checking on Delivery 18...............................

2.2.2 Installing the Servomotor 19............................

2.2.3 Installing the Servopack 22.............................

must read

2.3 Connection and Wiring 25.....................

2.3.1 Connecting to Peripheral Devices 25.....................

2.3.2 Main Circuit Wiring and Power ON Sequence 28............

2.3.3 Examples of Connecting I/O Signal Terminals 30...........

2.4 Conducting a Test Run 37.....................

2.4.1 Test Run in Two Steps 37..............................

2.4.2 Step 1: Conducting a Test Run for Motor without Load 39....

2.4.3 Step 2: Conducting a Test Run with the Motor Connected

to the Machine 4 3....................................

2.4.4 Supplementary Information on Test Run 45................

2.4.5 Minimum User Constants Required and Input Signals 47......

BASIC USES OF Σ-SERIES PRODUCTS

2.1.1 Notes on Use

2.1 Precautions

This section provides notes on using Σ-Series products.

2.1.1 Notes on Use 16...................................................

2.1.1 Notes on Use

NOTE Always note the following to ensure safe use.

Two types of supply voltage are available, 100 V and 200 V.

Both Σ-Series Servomotor and Servopack have 100 V and 200 V types. Be sure to use the correct type.

Voltage label

Type NP

Always use the SGM/SGMP Servomotor and DR2 Servopack in pairs.

The SGM/SGMP Servomotor cannot run without the DR2 Servopack.

Direct connection

Do not plug the SGM Servomotor directly into the commercial power supply. (Direct connection to the commercial power supply will damage the Servomotor.)

200 V or 100 V power supply

Damage will result!

Do not change wiring when power is ON.

Always turn the power OFF before connecting or disconnecting a connector. (Except for Digital Operator (Type: JUSPOP02A-1))

CHARGE Lamp Extinguished

Always turn the power OFF before connecting or disconnecting a connector.

Note that residual voltage still remains in the Servopack even after the power is turned OFF.

Even after the power is turned OFF, residual voltage still remains in the capacitor inside the Servopack. Before inspection is to be performed, make sure if CHARGE lamp is extinguished.

CHARGE Lamp

Careful!

Residual voltage remains in capacitor

Check if CHARGE lamp goes OFF.

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