The BL20-4DO-24VDC-0.5A-P (Ident-No: 6827023) is a hot-swappable electronic slice that plugs into a passive base module (like the BL20-S3T-SBB). It features PNP (Positive) switching logic and provides galvanic isolation via optocouplers between the field level and the internal system electronics. This separation protects your PLC and network gateway from field-side electrical noise and surges.
