A - 5 
 
INTRODUCTION 
Thank you for purchasing the Mitsubishi general-purpose programmable logic controller MELSEC-Q Series. 
Always read through this manual, and fully comprehend the functions and performance of the Q Series PLC 
before starting use to ensure correct usage of this product. 
Make sure that this manual is delivered to the final user. 
 
CONTENTS 
 
SAFETY INSTRUCTIONS............................................................................................................................A-   1 
REVISIONS...................................................................................................................................................A-   4 
CONTENTS...................................................................................................................................................A-   5 
About Manuals ..............................................................................................................................................A- 13 
Using This Manual.........................................................................................................................................A- 13 
Conformation to the EMC Directive..............................................................................................................A- 13 
Generic Terms and Abbreviations................................................................................................................A- 14 
Component List .............................................................................................................................................A- 14 
Section 1   Product Specifications and Handling 
 
1. Product Outline  1-  1 to 1- 28 
1.1 Positioning control....................................................................................................................................1-  2 
1.1.1 Features of QD75..............................................................................................................................1-  2 
1.1.2 Purpose and applications of positioning control............................................................................... 1-  5 
1.1.3 Mechanism of positioning control .....................................................................................................1-  7 
1.1.4 Overview of positioning control functions.........................................................................................1-  8 
1.1.5 Outline design of positioning system...............................................................................................1- 18 
1.1.6 Communicating signals between QD75 and each module.............................................................1- 19 
1.2 Flow of system operation........................................................................................................................1- 22 
1.2.1 Flow of all processes........................................................................................................................1- 22 
1.2.2 Outline of starting .............................................................................................................................1- 24 
1.2.3 Outline of stopping ...........................................................................................................................1- 26 
1.2.4 Outline for restarting.........................................................................................................................1- 27 
2. System Configuration  2-  1 to 2-  6 
2.1 General image of system.........................................................................................................................2-  2 
2.2 Component list ......................................................................................................................................... 2-  4 
2.3 Applicable system ....................................................................................................................................2-  5 
2. How to check the function version, serial No............................................................................................ 2-  6 
3. Specifications and Functions  3-  1 to 3- 20 
3.1 Performance specifications......................................................................................................................3-  2 
3.2 List of functions  .......................................................................................................................................3-  4 
3.2.1 QD75 control functions......................................................................................................................3-  4 
3.2.2 QD75 main functions.........................................................................................................................3-  6