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Modicon TM3 Expansion I/O modules for M221, M241, M251

Modicon TM3 I/O system specially designed for the Modicon M221, M241 and M251 logic controllers!

Part of Modicon

Flexible I/O expansion modules for M221, M241 & M251 Modicon PLCs. Includes digital and analog as well as mixed I/O. Also, includes special modules designed specifically for Machine Safety control. Up to 7 modules can be connected directly to the PLC. Also, the system can be expanded to include an additional set of 7 modules for a total of 14 modules and a couple hundred I/O points.

Modicon TM3 Expansion I/O modules for M221, M241, M251
  • Features

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    Modicon TM3 I/0 system - your choice for flexible and customizable expansion of I/O terminals!
    The specially developed Modicon TM3 I/O system enables flexible and customizable expansion of the I/O terminals in all of the controllers. Up to 14 terminals can be added to the controllers without tools. When the terminals are plugged in, their contacts are electrically linked to both the controller and the adjacent terminal. This high-speed expansion bus is 10 times faster than traditional solutions.

    The Modicon TM3 offer provides a large range of I/O systems to enhance the capabilities of Modicon M221, M241M251 logic controllers:

    • Digital I/O modules which can be used to create configurations with up to 264 digital I/O.
    • Analog I/O modules which can be used to create configurations with up to 114 analog I/O and are designed to receive, amongst other things, position, temperature or speed sensor signals.
    •  Expert modules for the control of TeSys motor starters which simplify wiring up the control section due to connection with RJ45 cables.
    • Functional Safety modules which simplify wiring and can be configured in the SoMachine Basic software.

    In addition, the Modicon TM3 expansion system is flexible due to the possibility of remotely locating some of the Modicon TM3 modules in the enclosure or another cabinet (up to 5 meters away, using a bus expansion system. It is common to the whole range of Modicon M221, M241 and M251 logic controllers, meaning that the model of controller can be revised without changing expansion module.

    The Modicon TM3 is a MachineStruxure I/O system. The NEXT generation of MachineStruxure™ from Schneider Electric is an intuitive solution for machine automation with all the features and functions you need to build machines that will improve your bottom line. From design and development, to commissioning and maintenance, MachineStruxure is a complete machine building solution with benefits all through the machine life cycle.


    Special feature:
    Modicon TM3 expansion modules have been designed with a simple interlocking assembly mechanism. A bus expansion connector is used to distribute data and the power supply when assembling the Modicon TM3 expansion modules with logic controllers.
    • Flexibility to be used across multiple PLC platforms such as Modicon M221, M241 & M251 providing a common I/O expansion system compatible with a wide range of machine automation controllers


    • TM3 Safety Cat3
    • TM3 8IO
    • TM3 32IO
    • TM3 Exp and Safe
    • TM3 24IO

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