SIMATIC S7. DIGITAL INPUT SM 321. OPTICALLY ISOLATED. 4 DI. 24V DC. NAMUR/DIN 19234. F. SIGNALS F HAZARDOUS AREAS. CAPABLE OF DIAGNOST..PTB-TESTED
SIMATIC S7-300. DIGITAL INPUT SM 321. OPTICALLY ISOLATED. 32 DI. 120V AC. 1 X 40 PIN
SIMATIC S7/PCS7. SM 321 DIGITAL INPUT MODULE. 16 DI. 24V DC. 1 X 40 PIN. CAPABLE OF DIAGNOSTICS. FOR CONTACTS (CONNECTED/ UNCONNECTED). NAMUR SENSOR. 3/4-WIRE-BERO. WITH FLUTTER MONITORING. PULSE LENGTHENING. WIRE BREAK DETECTION. IM153-2 INTERFACE MOD. REQUIRED
SIMATIC S7-300. DIGITAL INPUT SM 321. OPTICALLY ISOLATED 32DI. 24 V DC. 1 X 40 PIN