Motion controller
ACS Motion Control SPiiPlus EC-PX controller
EtherCAT MainDevice motion controller for 4 up to 128 axes with a maximum EtherCAT cycle rate of 10 kHz, panel or DIN mounting, and TCP/IP, EtherNet/IP, Modbus and RS-232 host links.
Need this part, a replacement or a better-fit option? Our engineers help with selection, procurement, sourcing, competitive pricing and lead times.
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Need ACS Motion Control parts, a replacement or another suitable option? Send your part number or describe the application. We’ll review the requirement and help with product selection, sourcing, pricing and lead times.
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Key specifications
| Data / bus | EtherCAT, EtherNet/IP, Modbus |
|---|---|
| Fieldbus | EtherCAT MainDevice; host TCP/IP, EtherNet/IP, Modbus, RS-232 |
| Axes | 128 |
| Axes max | 128 |
| Cycle | EtherCAT up to 10 kHz |
Summarised in our own words from PI Group (Physik Instrumente)'s published data; series maxima, individual models vary. Last checked 2026-10-30. Source 1 · Source 2
Notes on this data
Launched 2024 per ACS history.
Specify Motion is not affiliated with PI Group (Physik Instrumente). ACS Motion Control and SPiiPlus EC-PX are used only to identify the product. Comparisons use published figures; always confirm against the current datasheet.
Engineer support
Speak to our engineers about your project
Our experienced engineers are on hand, ready to help with your project. Whether you need the ACS Motion Control SPiiPlus EC-PX itself, help sourcing it, or a modified or custom design built around your load, speed and space, tell us what the machine has to do and we'll come back with the right option.
- Help sourcing SPiiPlus EC-PX and spares for installed machines
- Modified and custom designs when a catalogue part doesn't fit
- Complete axis: motor, drive, gearing and feedback matched together
Typical applications
What a motion controller is
A motion controller plans and coordinates movement for one or more axes, sending position, velocity or torque commands to servo or stepper drives. It generates trajectories with defined acceleration and jerk, synchronises axes for interpolation, electronic gearing and camming, and handles homing, limits and registration inputs. Commands reach drives over pulse, analogue or, most commonly now, EtherCAT and other real-time networks. Many controllers also include PLC functions to IEC 61131-3, combining logic and motion.
When engineers choose a motion controller
Choose a dedicated motion controller when a machine needs coordinated multi-axis motion beyond basic point-to-point moves, such as robots, gantries, packaging and CNC. It gives deterministic timing and motion libraries. The trade-offs are cost, programming effort and ecosystem lock-in. For simple machines with a few independent axes, a PLC with motion function blocks or intelligent drives with stored moves may be enough.
How to specify the ACS Motion Control SPiiPlus EC-PX
Send these with your enquiry and an engineer can confirm the right SPiiPlus EC-PX variant or an equivalent:
- Number of axes and drives
- Network and cycle time (ms)
- Motion functions: interpolation, camming, robotics
- Programming environment and languages
- I/O and expansion
- HMI and connectivity
- Safety integration
Common mistakes to avoid
- Choosing a controller that does not support the drives' network
- Underestimating cycle time needs for many axes
- Ignoring programming tools and skills in the team
- Not planning for future axis count
ACS Motion Control SPiiPlus EC-PX: frequently asked questions
Can you help replace ACS Motion Control SPiiPlus EC-PX or source the original?
Send the full model code, quantity and required date. Our engineers can check original-part availability and assess suitable alternatives, including Motion Control Products options where appropriate. We confirm compatibility and any changes needed before recommending a replacement.
What is the ACS Motion Control SPiiPlus EC-PX?
EtherCAT MainDevice motion controller for 4 up to 128 axes with a maximum EtherCAT cycle rate of 10 kHz, panel or DIN mounting, and TCP/IP, EtherNet/IP, Modbus and RS-232 host links. Published series figures include axes 128. It is made by PI Group (Physik Instrumente); Specify Motion can help source it or propose an equivalent.
Who makes the ACS Motion Control SPiiPlus EC-PX?
The ACS Motion Control SPiiPlus EC-PX is made by ACS Motion Control (PI Group (Physik Instrumente)) and is listed here for engineers comparing options. Specify Motion is not affiliated with PI Group (Physik Instrumente); brand names are used only to identify the product.
What is the axes of the ACS Motion Control SPiiPlus EC-PX?
The published series maximum axes is 128. Individual models and sizes in the SPiiPlus EC-PX range vary, so check the exact variant against your duty cycle, mounting and environment, or ask our engineers to confirm the right size for you.
Is there an alternative to the ACS Motion Control SPiiPlus EC-PX?
We can assess suitable replacement options. Our engineers can review the original model and propose options for your load, speed and environment. An engineer confirms the fit against your application before recommending anything.
What is the difference between a motion controller and a PLC?
A PLC handles machine logic, sequencing and I/O. A motion controller specialises in trajectory planning and coordinating axes. Many modern controllers combine both, running PLC logic and motion libraries on one CPU. Choose based on axis count, motion complexity and timing requirements.
Why is EtherCAT common for motion control?
EtherCAT offers short cycle times, precise synchronisation using distributed clocks and simple cabling, which suit coordinated multi-axis motion. Many drives and I/O devices support it. Other real-time networks such as PROFINET IRT and Sercos are also used, so check what the drives and controller support.
Further reading: How to select a motion controller or plc · Controllers and PLCs
Other motion controller series
Engineer support
Our engineers are ready to help with your project
Tell us about your project and how you use the ACS Motion Control SPiiPlus EC-PX: the load, speed, duty and environment. An experienced engineer will review it and reply, normally within one working day.
- Reviewed by an engineer, not an autoresponder
- Like-for-like and better-fit alternatives
- Standard, modified and custom options
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