Siemens 6ES7221-1EF00-0XA0 Programmable Logic Controller

Siemens 6ES7221-1EF00-0XA0 is an EM 221 digital input module for the SIMATIC S7-200 family, delivering eight optically isolated digital inputs for use with S7-21x CPUs. It accepts AC input signals at 120 V or 230 V, enabling direct connection of industrial sensors and switches to the PLC. As part of the S7-200 I/O family, the EM 221 module provides isolated input channels to help protect the controller from field wiring disturbances. This module is a discontinued part; Siemens ended its lifecycle on October 1, 2013, though it may still be found through secondary markets and repair services for legacy installations.