Designed for high-speed sub-bus communications within automated systems, the Omron CJ1W-SRM21 facilitates seamless I/O integration as a dedicated CompoBus/S Master Unit for CJ-series programmable logic controllers. This module functions as an efficient remote I/O terminal hub, allowing CJ1 CPU architectures to communicate with up to 32 remote slave terminals. By offloading local I/O wiring to a localized high-speed bus network, this module significantly reduces physical wiring paths while retaining extremely low I/O response times. System engineers can dynamically allocate memory allocations between 256 or 128 discrete I/O points depending on network complexity and cycle time requirements.
| Parameter | Value |
|---|---|
| Manufacturer | Omron Industrial Automation |
| Model Number | CJ1W-SRM21 |
| Unit Classification | CJ-series Special I/O Unit |
| Communication Protocol | CompoBus/S |
| Max. Connectable Nodes | 32 remote slave terminals |
| Allocated CIO Words | 20 words (for 256 I/O) or 10 words (for 128 I/O) |
| Current Consumption | 0.15 A at 5 VDC |
| Transmission Distance | 100 m (High-Speed), 500 m (Long-Distance) |
| Shipping Weight (Calculated) | 0.25 kg |
| Package Dimensions (Calculated) | 15.0 x 10.0 x 4.0 cm |
| Terminal Block Pin | Function / Signal Assignment |
|---|---|
| BD H | CompoBus/S Communications Line (High) |
| BD L | CompoBus/S Communications Line (Low) |
| NC | No Connection |
The CJ1W-SRM21 serves as a drop-in replacement for older CompoBus systems and integrates directly onto CJ-series backplanes. Note that if you are migrating from CS-series architectures using CS1W-SRM21, the memory mapping and CIO allocations match conceptually, but the physical form factor of the module is strictly CJ-series. Ensure you verify backplane physical depth limitations when arranging the CJ1W card in high-density control panels.
A common field misconfiguration involves mixing CompoBus/S slave speeds. All connected slaves on the same trunk network must be configured to the same transmission mode as the CJ1W-SRM21 (either all High-Speed or all Long-Distance). If there is a mismatch, the Master Unit will generate persistent participation flags or fail to establish communication with the misplaced nodes entirely.
Always power cycle the PLC chassis after modifying the front-panel rotary unit number switches or the internal DIP switches. The CJ CPU registers the CJ1W-SRM21 hardware parameters and physical address configurations only during its initial boot sequence. Additionally, ensure that standard 100-ohm terminating resistors are installed at both physical ends of the communication trunk to eliminate signaling echoes and line noise.
CRITICAL WARNING
Do not install or remove the CJ1W-SRM21 module while the PLC backplane is powered. Failure to completely isolate power before handling modules can cause catastrophic damage to the CJ-series CPU bus interface, corrupt CPU user memory, or cause intermittent hardware exceptions on adjacent modules.
Isolate the master power supply supplying the CJ-series backplane and auxiliary field bus networks.
Configure the front-panel rotary switch to assign the desired Unit Number (0 to 95) and select the corresponding I/O configuration via the unit's DIP switches.
Align the top and bottom guides of the module with the CJ rack slots and push the module firmly until the lock levers click into place.
Wire the BD H and BD L terminal lines using dedicated twisted-pair CompoBus cable and double-check terminal tighteners to prevent loose physical contacts.
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Returns & Warranty
Manufacturer: Omron
Product No.: CJ1W-SRM21
Country of origin:Japan
Product Type: PLC Communication Modules
Payment: T/T, Western Union
Weight: 1200g
Dimensions: 15.0 x 10.0 x 4.0 cm
Shipping port: Xiamen
Warranty: 12 months
Designed for high-speed sub-bus communications within automated systems, the Omron CJ1W-SRM21 facilitates seamless I/O integration as a dedicated CompoBus/S Master Unit for CJ-series programmable logic controllers. This module functions as an efficient remote I/O terminal hub, allowing CJ1 CPU architectures to communicate with up to 32 remote slave terminals. By offloading local I/O wiring to a localized high-speed bus network, this module significantly reduces physical wiring paths while retaining extremely low I/O response times. System engineers can dynamically allocate memory allocations between 256 or 128 discrete I/O points depending on network complexity and cycle time requirements.
| Parameter | Value |
|---|---|
| Manufacturer | Omron Industrial Automation |
| Model Number | CJ1W-SRM21 |
| Unit Classification | CJ-series Special I/O Unit |
| Communication Protocol | CompoBus/S |
| Max. Connectable Nodes | 32 remote slave terminals |
| Allocated CIO Words | 20 words (for 256 I/O) or 10 words (for 128 I/O) |
| Current Consumption | 0.15 A at 5 VDC |
| Transmission Distance | 100 m (High-Speed), 500 m (Long-Distance) |
| Shipping Weight (Calculated) | 0.25 kg |
| Package Dimensions (Calculated) | 15.0 x 10.0 x 4.0 cm |
| Terminal Block Pin | Function / Signal Assignment |
|---|---|
| BD H | CompoBus/S Communications Line (High) |
| BD L | CompoBus/S Communications Line (Low) |
| NC | No Connection |
The CJ1W-SRM21 serves as a drop-in replacement for older CompoBus systems and integrates directly onto CJ-series backplanes. Note that if you are migrating from CS-series architectures using CS1W-SRM21, the memory mapping and CIO allocations match conceptually, but the physical form factor of the module is strictly CJ-series. Ensure you verify backplane physical depth limitations when arranging the CJ1W card in high-density control panels.
A common field misconfiguration involves mixing CompoBus/S slave speeds. All connected slaves on the same trunk network must be configured to the same transmission mode as the CJ1W-SRM21 (either all High-Speed or all Long-Distance). If there is a mismatch, the Master Unit will generate persistent participation flags or fail to establish communication with the misplaced nodes entirely.
Always power cycle the PLC chassis after modifying the front-panel rotary unit number switches or the internal DIP switches. The CJ CPU registers the CJ1W-SRM21 hardware parameters and physical address configurations only during its initial boot sequence. Additionally, ensure that standard 100-ohm terminating resistors are installed at both physical ends of the communication trunk to eliminate signaling echoes and line noise.
CRITICAL WARNING
Do not install or remove the CJ1W-SRM21 module while the PLC backplane is powered. Failure to completely isolate power before handling modules can cause catastrophic damage to the CJ-series CPU bus interface, corrupt CPU user memory, or cause intermittent hardware exceptions on adjacent modules.
Isolate the master power supply supplying the CJ-series backplane and auxiliary field bus networks.
Configure the front-panel rotary switch to assign the desired Unit Number (0 to 95) and select the corresponding I/O configuration via the unit's DIP switches.
Align the top and bottom guides of the module with the CJ rack slots and push the module firmly until the lock levers click into place.
Wire the BD H and BD L terminal lines using dedicated twisted-pair CompoBus cable and double-check terminal tighteners to prevent loose physical contacts.
Global Express Shipping
Returns & Warranty
Orders are processed and delivered Monday-Friday (excluding public holidays).
For full eligibility, restocking fees, and international return details, please view our official Refund & Return Policy .
| Country of origin |
Japan
|
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