Mitsubishi has added a new generation of microcontrollers to its Melsec FX3 series of PLCs – claimed to be the world’s most successful line of compact controllers, with over nine million sold over the past 30 years. The new FX3G replaces the earlier FX1N series and offers: up to 128 I/O (expandable to 256); a CPU said to be faster than its main rivals (0.21µs per instruction cycle); and easy configuration through clip-on application modules.

There are three expansion options. On the right-hand side, the PLC accepts up to eight FX I/O, function and network modules; on the left-hand side, there is an “adapter bus” that takes up to four FX3U adapters to provide high-performance communications and analogue capabilities linked directly to the CPU. The third option is to use expansion slots on the front, where two expansion boards can be inserted to add serial communications (RS-232, RS-422 or RS-485) and analogue functions. A display module can also be plugged into the front.

The FX3G is hardware- and software-compatible with the FX1N controllers, so it can be “dropped” into existing applications. Its 32,000-step program memory enables it to handle significant automation tasks and to use structured programming techniques.

For positioning applications, the new PLC has six high-speed counters operating at up to 60kHz. There are also pulse outputs up to 100kHz for controlling up to three stepper or servo motors. Up to eight variable speed drives can be connected directly to the PLC and controlled using dedicated instructions.

Accompanying programming software supports the five IEC 61131-3 programming languages. The instruction set includes more than 120 dedicated application instructions.

The FX3G is available in 14, 24, 40 and 60 I/O models. Initial 100-240V AC versions will be followed by 24V DC versions for specialist applications.

The FX3G supports Profibus, CC-Link, Ethernet and CANopen, plus data communications via up to three serial interfaces. A USB port and an RS-422 port are built into the front panel, with other connections being made via interface modules.   

UK prices start at less than £300.