Siemens 6ES7321-7RD00-0AB0 SIMATIC S7-300 SM321 Digital Input
Siemens 6ES7 321-7RD00-0AB0 SIMATIC S7-300 SM 321 Digital Input Module, (4) NAMUR/DIN 19234 Digital Inputs, 24V DC Supply Voltage, 20-Pin, for signals from Hazardous Areas (Ex(i) protection), with Diagnostic Functions, PTB tested, Optically Isolated