Product Overview

The 6ES5430-4UA14​ is a SIMATIC S5-430 series digital input module from Siemens, configured as a 32-channel, 24 V DC, floating (galvanically isolated) input submodule in the compact “Version U” mechanical form. It occupies a single slot in a SIMATIC S5 central rack — primarily S5-115U, secondarily S5-135U — and acquires 24 V DC sensor signals (PNP proximity, pushbutton, limit switch, motor-aux contact, valve-end-switch, drive-status relay) while keeping the input channel groups electrically isolated from the rack/S5 M reference. This floating topology is the defining difference between the 430 family and the 420 family: where the 6ES5420-4UA11​ we covered previously bonds all 32 inputs to a common M, the 6ES5430-4UA14​ breaks the 32 inputs into isolated groups (typically two groups of 16 or four groups of 8, depending on the exact 430 sub-revision’s internal bridge/default — S5-430 32-point DIs conventionally group in 8s or 16s with per-group common terminals on the front connector), each group referencing its own sensor-supply 0 V rather than the S5 rack 0 V.The “Version U” compact mechanical means the 6ES5430-4UA14​ is shorter in depth than a standard S5 module, clearing shallower cabinets or sitting alongside deeper neighbours (S5-465 analogue, S5-470 CP, etc.) without back-of-rack clearance fights — the same mechanical rationale as the 420-4UAxx line, but applied to the isolated DI branch. Within S5-115U panels, the 6ES5430-4UA14​ gets specified whenever the 24 V DC sensor supply is not derived from the S5 PS 24 V auxiliary — typical cases being: sensors fed from a drive-DC bus (VFD DC-link derived 24 V, which floats relative to S5 M), sensors on a separately earthed PSU in a zone-separated cabinet, or intrinsically safe / segmented sensor buses where tying every sensor 0 V to S5 M would create ground loops or violate segregation. In those topologies, forcing a 420 non-floating module creates phantom inputs or unpredictable behaviour; the 6ES5430-4UA14​ is the correct catalogue answer.Like all S5 I/O, the 6ES5430-4UA14​ is long out of Siemens active production, but the S5-115U/135U installed base it serves is still sizable in steel, cement, water/wastewater, legacy packaging, crane/hoist, and Eastern European/Asian machinery from the 1990s–2000s export wave. NOS and refurbished units of the 6ES5430-4UA14​ trade actively because a failed floating DI in a running rack is a stop-event: if a drive-status relay or safety-chain segment is on a floating group and the module drops, the CPU sees the input go false and the safety or interlock logic trips. Supplying the 6ES5430-4UA14​ means supplying the exact 32×24 V DC floating density in compact U — not a 420 substitute (wrong topology) and not a 430 in standard/K depth (cabinet clash risk). The 4UA14 suffix places it late in the 430-4 sub-revision chain (4UA11 → 4UA12 → 4UA13 → 4UA14), so it typically interchanges with earlier 4UAxx without project change, which is why many spare planners just specify “6ES5430-4UA14” as the catch-all 430 compact-U 32-DI.

Technical Specifications