Core Technology

Core Technology 06Programmable Logic Controller

About Programmable Logic Controller

Programmable logic controller (PLC) is used to control various automatic machines and indicates the control device to run the software described using a programming language called a ladder diagram that encodes relay circuits. The purpose of use varies widely, and thus the generalizability and flexibility of the system structure are crucial. Sodick’s PLC can be expanded from 16 I/O points (min.) to 65,536 I/O points (max.). In addition, it can control up to a maximum of 60 motor bearings.


  1. Space-saving: H131 x W31 x D98 mm (excludes the extruding parts of the CPU unit)
  2. Use of 100 Mbps LAN cables for inter-unit communication eliminated wiring and achieved high performance
  3. Capable of various kinds of motor control when used with motion units
  4. The screen software running on the display unit (SmART) allows you to customize operation screens to your needs
    Users can “drag and drop” available parts on SmART, place them wherever they want, and create the screen. Users can develop an operation screen without knowing the underlying programming language
  5. Offers multiple languages in response to globalization. Users can unify management of display languages
  6. Perform simulation of the ladder diagram that is created by ladder diagram software
    Users can easily perform checks on the operation of the output of each IO, internal relay, and counters, etc. by sending an input waveform to the simulator
  7. Equipped with an online debugging function
    PLCs can check various IOs and internal variables during real-time operation

Background of Development

In recent years, manufacturing and production worksites have shifted to new developing countries, mainly in Southeast Asia. For this reason, automation has become vital in Japan to meet demand, in terms of both cost and quality. In these new developing countries also, increasing labor costs is unavoidable, and it is expected that the move toward automation will spread further. Considering the current situation, in order to correspond to such social and structural changes, Sodick has developed PLCs for various automatic controls, not only for NC unit but also for general purpose use. This allows sequential control of machine tools, connection with peripheral equipment, and automatic control of industrial machines, all of which are pushing automation forward.