CJ1W-DRM21
| Specification | Details |
| Manufacturer | OMRON |
| Model | CJ1W-DRM21 |
| Product type | DeviceNet Master/Slave Unit |
| Series | CJ-Series |
| Module type | CPU Bus Unit / Communication Unit |
| Communication protocol | DeviceNet |
| Function | Master and Slave |
| Communication port | 1 × DeviceNet |
| Baud rate | 125 / 250 / 500 kbps |
| Maximum nodes | 64 nodes including Master, Slaves and Configurator |
| Maximum slaves | 63 |
| Communication supply | 11–25 VDC |
| Current consumption | Communication: 18 mA max.; internal circuit: 290 mA max. |
| Max. I/O as Master | Up to 32,000 points |
| Max. I/O as Slave | Up to 4,800 points |
| Maximum message length | 542 bytes |
| Units per PLC | Up to 16 with user-defined allocation |
| Dimensions | 31 × 90 × 78.7 mm |
| Weight | Approx. 120 g |