What this module is and where it fits
The Omron GRT1-OD4G-3 is a SmartSlice output module – four solid-state outputs on a DIN-rail mount, powered by 24 VDC. It lives inside a CJ, CS, or NJ series rack, not a CP1 series. The screw terminals make wiring straightforward, and the IP20 enclosure keeps it suited for clean indoor cabinets.
How it compares to the CP1W-32ET / ET1
A common question is whether the GRT1-OD4G-3 swaps into a panel built around a CP1W-32ET or CP1W-32ET1. Short answer: no—these are different platforms. The GRT1 is a SmartSlice module for CJ/CS/NJ-series controllers; the CP1W modules belong to the CP1-series compact PLC. Even the bus architecture isn't shared. Also, output count: 4 vs 32. So if you're sourcing for a CP1-based design, the GRT1 won't drop in without changing the entire backplane and program.
Installation and environment notes
DIN rail mount. Screw terminals accept solid or stranded wire. Operating range is -10°C to 55°C. cULus, CE, and Lloyd's approvals.