Product Core Brief
- Model: F3SP21-0N
- Brand: YOKOGAWA
- Series: FA-M3 Programmable Logic Controller
- Core Function: Sequence control CPU module for FA-M3 PLC systems, executing ladder logic and managing I/O, communication, and motion modules.
- Product Type: PLC CPU Module
- Key Specs: FA-M3 sequence control CPU | SIO port for programming and PC link | FA-M3 base slot
- Condition: New Original / New Surplus
Key Technical Specifications
| Parameter | Detail |
|---|---|
| Brand | YOKOGAWA |
| Model Number | |
| Product Type | Sequence Control CPU Module |
| Applicable System | YOKOGAWA FA-M3 PLC |
| Mounting | FA-M3 base module slot |
| Communication | SIO port for programming / PC link; Ethernet link via compatible F3LE module |
| Compatible I/O | FA-M3 digital, analog, positioning, counter, and communication modules |
| Typical Applications | Packaging machinery, material handling, assembly lines, process control, OEM machine control |
| Origin | Japan |
| Condition | New Original / New Surplus |
Note: Exact program capacity, scan time, memory size, SIO/Ethernet performance, and supported instruction set should be confirmed against the official FA-M3 CPU manual or the module nameplate before final integration.
Product Introduction
The F3SP21-0N is a sequence control CPU module for YOKOGAWA FA-M3 PLC systems. It serves as the controller for the FA-M3 rack, executing ladder programs, scanning I/O modules, and coordinating communication with HMIs, drives, and other field devices.
For maintenance teams and system integrators, this module is useful when replacing a failed FA-M3 CPU or building a spare for an existing machine. Because it belongs to the FA-M3 family, it shares the same modular architecture as other F3SP-series CPUs, allowing it to work with standard FA-M3 power supplies, base modules, and I/O cards.
QA & Testing SOP
We verify every CPU module before dispatch because a bad processor can stop an entire machine.
- Label & Suffix Verification: Confirm F3SP21-0N on the faceplate. The FA-M3 CPU family includes multiple variants, so the exact model must match the existing configuration.
- Visual & Anti-Counterfeit Inspection: Inspect the PCB, connectors, battery compartment, and housing for rework, corrosion, moisture damage, or non-OEM components.
- Backplane Connector Check: Examine the base module contacts for bent pins, oxidation, or debris. A poor backplane connection can cause intermittent CPU faults.
- Power-Up & LED Status Check: Install the module in a compatible FA-M3 test rack with the correct power supply, apply power, and verify RUN/STOP/ERROR indicators.
- Programming Port Test: Connect to the SIO port and confirm that the programming tool can communicate with the CPU.
- ESD-Safe Packaging: Each unit is packed in anti-static material with desiccant and sealed for shipment.
Installation Pitfalls & Guide
❗ Do not substitute F3SP21-0N with other F3SP CPUs without verification. FA-M3 CPUs such as F3SP25, F3SP28, F3SP35, and F3SP58 differ in performance, memory, and communication features. Using the wrong CPU can break the program or I/O mapping.
❗ Confirm the power supply module. FA-M3 CPUs require the correct F3PU-series power supply. An undersized or incompatible power module can cause unstable operation or repeated CPU resets.
❗ Check the base module slot rules. The CPU must be installed in the correct slot according to the FA-M3 base module configuration. Installing it in a non-CPU slot will prevent the system from starting.
❗ Back up the program before replacement. If the existing CPU is still accessible, download and save the ladder program, I/O configuration, and parameter settings before swapping modules.
Replacement Steps:
- Pre-Install: Back up the PLC program, confirm the F3SP21-0N model, and verify the power supply and base module.
- Removal: Power down the rack if required, disconnect communication cables, and remove the CPU module.
- Install: Seat the new F3SP21-0N in the correct CPU slot, reconnect cables, and verify that the module is fully seated.
- Power-On Test: Restore power, check LED status, connect the programming tool, verify communication, and load or confirm the PLC program.
Technical FAQ
Is F3SP21-0N a FA-M3 CPU module? Yes. It is a sequence control CPU module for the YOKOGAWA FA-M3 PLC family.
Can it communicate over Ethernet? The F3SP21-0N supports SIO-based PC link and can work with compatible FA-M3 Ethernet communication modules for Ethernet connectivity. Confirm the exact F3LE module and driver compatibility before setup.
Is it compatible with FA-M3 I/O modules? Yes. It is designed to work with standard FA-M3 I/O, positioning, counter, and communication modules installed in the same rack or extension units.
Can I replace another F3SP CPU with F3SP21-0N? Not automatically. Different FA-M3 CPUs have different performance levels, memory sizes, and supported features. Use the same model when possible, or verify compatibility with the OEM documentation.
