Technical Specifications
| Parameter Name | Parameter Value |
|---|---|
| Product Model | 6ES5090-8MA11 |
| Manufacturer | Siemens (SIMATIC S5) |
| Product Type | Compact Programmable Logic Controller (S5-90U series, kit config) |
| Digital Inputs | 10 × 24 V DC, sink/source configurable |
| DI Input Current | ~7–10 mA per point |
| DI Isolation | Optocoupler (input ↔ internal) |
| Digital Outputs | 6 × relay, NO dry contact |
| Relay Contact Rating | 5 A resistive @ AC 250 V / DC 30 V |
| Relay Mechanical Life | >10,000,000 operations |
| Relay Electrical Life | >100,000 operations @ rated load |
| Response Time (Relay) | ~10 ms on / ~10 ms off |
| Mains Supply | 115 V AC / 230 V AC, wide-range auto-adaptive |
| Power Consumption | ~30 VA (no-load) |
| Program Memory | RAM (battery-backed) + EPROM submodule option |
| Data Retention | Internal lithium battery, typ. 1–2 years (replaceable) |
| Programming Software | STEP 5 (v5.x / v6.x / v7.x); no STEP 7 / TIA support |
| Operating Temperature | 0 °C to +55 °C |
| Storage Temperature | –25 °C to +70 °C |
| Relative Humidity | 5 % to 95 % (non-condensing) |
| Mounting | 35 mm DIN rail (EN 60715) |
| Dimensions (W × H × D) | ~90 × 80 × 60 mm |
| Weight | ~0.3 kg |
| Protection Class | IP20 |
| Certifications | CE |
Main Features and Advantages
True all-in-one compactness. The 6ES5090-8MA11 was, for its 1990s-era launch window, unusually integrated: CPU, 115/230 V AC PSU, 10 DI, and 6 relay DO in a 90-mm-wide shell. No separate S5 power supply module, no IM interface module, no rack — just clip onto DIN rail, land 115/230 V L/N, land 10 DI sensors, land 6 DO loads on the removable terminal, and the 6ES5090-8MA11 is running. For OEMs building form-fill-seal heads, cartoner infeeds, small press safeties, or building-HVAC plant-room aux panels, this collapsed footprint saved an entire “PSU + CPU + DI + DO” slice of DIN real estate.Wide-range 115/230 V AC with zero configuration. Most compact PLCs of that era demanded a jumper or selector for 120 vs. 230 V. The 6ES5090-8MA11 auto-adapts across the full band — same unit ships to a German 230 V panel and a North American 120 V panel without opening the housing. For EPCs and OEMs selling machines to both regions, this eliminated the “wrong-PSU SKU” mistake that plagued narrower-input competitors.Battery-backed RAM + EPROM submodule path. The 6ES5090-8MA11 stores the STEP 5 program in internal RAM kept alive by a replaceable lithium cell (1–2 year hold typical). For machines where power cycles are frequent — packaging lines powered down nightly, seasonal building plants — this is risky unless the program is also burned to an S5-375 EPROM submodule plugged into the 6ES5090-8MA11 front socket. That dual-path (RAM for development, EPROM for production) was the S5-90U deployment pattern, and the 6ES5090-8MA11 kit format usually arrives with the EPROM socket accessible for field insertion.Sink/source DI flexibility. The 10 DI channels on the 6ES5090-8MA11 accept both PNP (source) and NPN (sink) 24 V DC field sensors — wire the 24 V to the M rail or to sensor + per convention. At ~7–10 mA per point, the DI stage is tolerant of long cable runs and marginal sensor drive. 2-wire sensors are supported with a max ~1 mA quiescent draw, adequate for most 24 V DC prox and photoelectric heads.Relay DO for mixed-load switching. The 6 DO on the 6ES5090-8MA11 are dry NO relay contacts rated 5 A at AC 250 V or DC 30 V — meaning they can directly switch 24 V DC solenoid valves, 230 V AC indicator beacons, small 1-ph contactors, and even single-phase heater loads without interposing SSRs. The ~10 ms relay operate/release time is fine for discrete logic but not for high-speed PWM — that limitation was accepted in the S5-90U target applications (sequence control, interlock, safety string, not servo).Kit-format convenience for legacy spares. Because the 6ES5090-8MA11 is a discontinued SKU, most buyers encounter it as a replacement in a 15–25-year-old machine. The “kit” bundling — CPU + front-connector + (often) PG-cable/adapter context — reduces the “arrived but missing the 3-row front plug” frustration that plagues loose S5-90U singles. For maintenance stores, the 6ES5090-8MA11 kit is the drop-in unit: unclip old, unplug 3-row terminal, clip new, replug, reload STEP 5 program from EPROM or PG backup.
