What it is and where it fits
The Omron CS1W-EIP21 is a Communications Module for the CS Series programmable controllers, providing Ethernet/IP connectivity via a backplane mount and RJ45 termination. It carries CE, cULus, Lloyd, and NK approvals, making it suitable for machinery applications requiring marine-class or general industrial certification.
Sourcing and lifecycle reality
This module is classified as obsolete per the manufacturer's lifecycle. No official replacement model has been published. Sourcing is through independent surplus channels; availability is quoted per RFQ. Confirm firmware revision and revision history with the seller to support any validation effort.
Mounting and integration note
The module snaps onto a CS Series CPU rack or expansion backplane. No additional DIN rail is required. When slotting into an existing configuration, verify the PLC program's network configuration to match the module's identity — the EIP21 appears as an Ethernet/IP adapter in the I/O table.