Deep dive · expands Platform · ch.3

The hardware family

This lesson covers the brain versus dumb I/O, couplers versus terminals, the CPU family, and the EtherCAT backbone that ties it all together. Build your own NX I/O island, then send a frame down the chain.

🧱 NX I/O islandEtherCAT backbone
01 · Build an island

Coupler + terminals

An NX I/O island starts with a coupler (the EtherCAT connection) and grows by clicking terminals onto it: digital in, digital out, analog, whatever the machine needs. Add a few, then run a frame.

02 · The whole family

Who's who in the rack

🧠 NJ / NX CPU units are the brain. Each one is a Machine Automation Controller: one CPU runs your Sysmac logic and a synchronised motion core together. The NX1P and NX1 take NX I/O units right beside the CPU, while the NX7 reaches all of its I/O over the network; NJ is rack-mount. The models span a whole ladder, shown below.

🔌 Couplers & terminals: a coupler joins an NX I/O island to EtherCAT; terminals are the cheap, dumb in/out slices you snap on beside it.

💻 NY IPC & Panel PC: the PC and the controller in one box, for when you need Windows alongside control to run a machine HMI, vision or data handling.

🌐 EtherCAT backbone: one frame visits every node in order, reads & writes on the fly, and returns. Its timing is deterministic to the microsecond.

03 · Choose your controller

The NJ/NX ladder

Every Sysmac controller is a Machine Automation Controller, with one CPU running logic and a synchronised motion core. The models climb a ladder from a compact built-in-I/O box to a 256-axis flagship. Tap a model to match it to a machine.

🪜 choose your controller↑ more axes · more performance

Source : industrial.omron.eu

04 · New here, or going deep?

Two tracks to the same controller

The left panel gives the plain-language version; the right one has real specs and a sizing rule. Either way you end up choosing the same box.

🌱 New to this? Beginner

Every Sysmac controller is a Machine Automation Controller: one CPU that runs your logic and the motion together.

  • The brain is the NJ or NX CPU; it makes every decision and keeps the axes in step.
  • Climb the ladder for more axes and speed: a small built-in-I/O box at the bottom, a 256-axis flagship at the top.
  • The couplers and terminals around it are just limbs: cheap in/out slices on EtherCAT.

Mental model: picture a band with one conductor (the CPU) keeping every musician (axis) perfectly in time. A bigger orchestra needs a bigger conductor.

⚙️ Go deeper Advanced

Pick the rung by axis count, cycle time and memory. Every rung shares the same Sysmac engine.

  • Compact / entry: NX1P (built-in 24/40-pt I/O), NJ1.
  • Mid-range: NX1, NJ3. Advanced: NX5, NJ5.
  • Flagship: NX7, with up to 256 axes, 80 MB program, 125 µs cycle and 2 parallel motion cores.
  • The NX1P and NX1 take I/O units beside the CPU (the NX7 cannot); NJ is rack-mount. Same programming, different chassis.

Selection rule: count coordinated axes and your tightest cycle. A few axes → NX1P / NJ1 / NX1; many axes or sub-ms motion → NX5 / NJ5 → NX7.

🧩
Picture it
One conductor keeping every musician in time. A small ensemble needs a modest conductor; a 256-piece orchestra needs the NX7.
⏱️
Pick the right controller in 10 seconds
1Small machine, want I/O inside the CPU? → NX1P (built-in I/O) or NJ1.
2Typical cell, a handful of axes? → NX1 / NJ3, step up to NX5 / NJ5 for more.
3Many synchronised axes, tight cycle, big program? → NX7 (256 axes, 125 µs).
⚠️
Common mistake
Treating NX and NJ as different performance "levels". They overlap: the NX1P and NX1 take I/O units beside the CPU, and NJ is rack-mount. Choose by chassis style and axis count, not by the letter.

Source : industrial.omron.eu

05 · Check yourself

One quick question

What's the job of the coupler at the head of an NX I/O island?