Product Overview

The 6ES5464-8MA21​ is a 4-channel, ±50 mV low-level analog input module within Siemens’ SIMATIC S5-464 family, engineered for the S5-100U compact PLC rack and the ET 100U distributed I/O station. Where most S5 analog input cards handle 0–10 V or 0/4–20 mA process signals from transmitters, the 6ES5464-8MA21​ is deliberately positioned at the opposite end of the amplitude spectrum: it directly digitises millivolt-level sensor outputs — thermocouple junctions, strain-gauge bridges, low-level pressure transducer elements — without requiring external signal conditioners. This makes the 6ES5464-8MA21​ the go-to AI card in S5-100U machines that were commissioned around furnace zones, extrusion barrel strings, environmental chambers, and small-signal weighing skids where a 10 V full-scale card would waste 99 % of its dynamic range.Each channel on the 6ES5464-8MA21​ uses a dual-slope integrating A/D converter, delivering 12 bits plus sign (two’s complement, left-justified, 2048 units = rated ±50 mV), with configurable channel count — the four inputs can be software-configured as 1, 2, or 4 active channels depending on scan-time versus resolution trade-offs. A defining differentiator of the 6ES5464-8MA21​ is its hardware linearization for Type J, K, and L thermocouples, implemented inside the module so the S5 CPU is offloaded from polynomial compensation math. The module also supports internal or external cold-junction compensation (the latter via an optional compensating box on the +9 V reference), making it viable for multi-zone temperature racks where a single 6ES5464-8MA21​ might acquire J-type thermocouples on barrel zones 1–4 of a plastics extruder.Electrically the 6ES5464-8MA21​ is a floating-design card: inputs are galvanically separated from the S5 backplane, with VDE 0160 insulation rated at 60 V AC between input group and +9 V, and up to 75 V DC / 60 V AC permissible between inputs and the central ground point. Noise rejection is engineered for electrically dirty shops — common-mode rejection ≥ 86 dB and series-mode rejection ≥ 40 dB against 50/60 Hz ±1 % mains harmonics, with integration time selectable as 20 ms (50 Hz regions) or 16.6 ms (60 Hz regions) via DIP on the module front. The 6ES5464-8MA21​ draws ~100 mA from the S5 rack’s +9 V rail (CPU-sourced) and dissipates ~0.7 W, making it thermally negligible even in dense S5-100U racks. Like the rest of the S5-464 range it sits in Siemens’ PM410 discontinued/spare-only lifecycle, with no named successor — which cements its role today as a continuity-engineering spare for plants that still run S5-100U or ET 100U nodes and cannot justify rewiring low-level sensor loops to a modern 0–10 V / 4–20 mA retrofit.

Technical Specifications