The Omron PLC CompoBus/S Master Unit CJ1W-SRM21 is a dedicated CPU Bus Unit designed to provide high-speed remote I/O control for Omron CJ-series programmable logic controllers. Leveraging the CompoBus/S protocol, this master unit enables efficient distributed I/O management with a maximum of 256 I/O points, making it an essential component for modern, scalable automation systems. Whether you are retrofitting an existing line or building a new control architecture, the CJ1W-SRM21 delivers deterministic, real-time communication with minimal latency, ensuring precise synchronization of sensors, actuators, and other field devices.
| Parameter |
Specification |
| Product Type |
CompoBus/S Master Unit |
| Model Number |
CJ1W-SRM21 |
| Network Protocol |
CompoBus/S (Remote I/O) |
| Maximum I/O Points |
256 points (max.) |
| Supported PLC Series |
CJ1, CJ2, CS1 |
| Mounting Type |
CPU Bus Unit (rack-mounted) |
| Communication Speed |
High-speed (proprietary CompoBus/S timing) |
| Operating Environment |
Industrial (0-55°C, 10-90% RH non-condensing) |
| Power Supply |
Via PLC backplane (5 V DC) |
| Weight |
Approx. 120 g |
| Dimensions |
31 x 90 x 65 mm (W x H x D) |
| Standards |
CE, UL, cUL |
- Communication Architecture: The CJ1W-SRM21 acts as a master on the CompoBus/S network, managing up to 256 remote I/O points across multiple slave stations. It uses a cyclic data exchange method for deterministic performance.
- Integration & Configuration: Easily configured via CX-Programmer software; no separate programming required for basic I/O mapping. The unit is automatically recognized by the PLC CPU.
- Network Topology: Supports daisy-chain and branch configurations using standard CompoBus/S cables, enabling flexible wiring in distributed automation cells.
- Diagnostics & Indicators: Front-panel LEDs provide real-time status of network communication, unit errors, and power supply – simplifying troubleshooting and maintenance.
- Compatibility: Fully compatible with all CompoBus/S slave devices, including I/O terminals, sensor amplifiers, and valve manifolds, ensuring broad application versatility.
- Environmental Resilience: Rated for industrial environments with robust noise immunity, wide temperature range, and vibration resistance per IEC standards.
What Does Our Clients Say
Mitsubishi MR-J4
Laura Navas
Great product!
2019/12/01
Keyence sensor
EQDR SALES
Original and fast!
2020/02/22