New Mitsubishi FX5U safety extension modules for PLC, simplify design.

New FX5U safety extension modules for PLC.


Mitsubishi Electric has strengthened its compact PLC series with the addition of two new FX5U safety extension modules. The modules allow users to create a compact, integrated safety system by connecting a safety extension module to a PLC. Developed and produced in conjunction with German safety maker SICK AG, the modules connect directly to FXU and FX5UC PLCs. Needing no special wiring or programming means machine builders and systems integrators can shorten their installation time for safety control systems.

Rotary switch simplifies programming

A key development requirement for the new modules was the set-up simplicity for the safety application. Each safety extension module has nine built-in safety programs. A rotary switch on the front of the module enables the user to select the one required to run their system. This eliminates the need for developing and loading sequence programs designed for safety control. It significantly reduces set-up times compared with conventional architecture.

The principle of simplicity also extends to visualization. The PLC’s built-in web server makes it easy to check the status of both the standard control and safety control system. Thus, the new modules reduce the man-hours required during the engineering phase of a safety application and simplify its setup.

FX5U safety extension

The FX5-SF-MU4T5 safety module and FX5-SF-8D14 safety input expansion module connect directly to the PLC. This eliminates the additional wiring needed for a traditional safety controller or when constructing a system with safety relays. Spring clamp terminals on the new modules simplify the connection of the safety I/O.

The new modules enable safety integration from within the compact PLC with no need for additional communication options. They enable an FX5 PLC to work as a both general-purpose and safety controllers. A single main safety module connected to an FX5 CPU provides four safety inputs and four safety outputs. Connecting an additional two safety input expansion modules provides up to twenty safety inputs and four safety outputs. Moreover, the addition of the new safety modules enables FX5U PLC users to build a compact safety system certified to Category 4, PLe and SIL3 international safety standards.

Mitsubishi has prepared a MELSEC iQ-F Series Safety Extension Module Configuration Guide to help users with the safety extension modules. The guide is also suitable for checking the system configuration, settings, and wiring of the safety extension module.

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