SIMATIC S7/PCS 7. SM 321 DIGITAL INPUT. 16 DI. DC 24/125V. 1 X 40-PIN FRONT CONNECTOR WITH WIRE BREAK DIAGNOSIS HARDWARE INTERRUPT DIAGNOSTICS
SIMATIC S7-300. DIGITAL INPUT SM 321. OPTICALLY ISOLATED. 8 DI. 120V/230V AC. 1 X 40 PIN. WITH 1 POINT PER COMMON
SIMATIC S7-300. DIGITAL INPUT SM 321. GALVANICALLY ISOLATED. 16 DI. DC 24V. 1 X 20 PIN. PROCESS INTERRUPT. DIAGNOSTICS. FIT FOR ISOCHRONE MODE
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