Technical Specifications
| Parameter Name | Parameter Value |
|---|---|
| Product Model | 6ES5090-8MA00 |
| Manufacturer | Siemens AG |
| Product Type | SIMATIC S5-90U CPU 103 Compact PLC Module |
| CPU Series | S5-90U (top-grade processor in compact family) |
| User Program Memory | 4 KB EEPROM (battery-free storage) |
| Data Memory | 1 KB (flags, timers, counters, battery-less RAM) |
| Integrated Digital Inputs | 16 points × 24 V DC (Sink/Source, 7 mA typical) |
| Integrated Digital Outputs | 12 points × relay (2 A @ 230 V AC / 24 V DC) |
| Supply Voltage | 24 V DC (19.2–28.8 V DC range) |
| Current Consumption | ≈ 60–80 mA @ 24 V (CPU only) |
| Bit Instruction Execution Time | ≈ 1.5 µs |
| Programming Interface | 1 × PG/OP (RS485, AS511 protocol, 9.6 kbps) |
| Expansion Capability | Up to 3 S5-90U expansion modules (EM 101 digital, EM 102 analog) |
| Scan Cycle Time | ≈ 1.5 ms / 1K statements (typical) |
| LED Indicators | RUN / STOP / SF (System Fault) / BAT (Battery Low) |
| Battery Backup | 3.6 V lithium battery for RAM retention (approx. 1 year) |
| Operating Temperature | 0°C to +60°C |
| Dimensions (W × H × D) | Approx. 75 mm × 125 mm × 110 mm (with terminals) |
| Protection Class | IP20 |
| Mounting | 35 mm DIN rail (EN 50022) |
| Certifications | CE, UL, CSA |
Main Features and Advantages
Integrated I/O for Compact Control Solutions: The Siemens 6ES5090-8MA00 stands out in the S5-90U family with its comprehensive onboard I/O configuration, offering 16 digital inputs and 12 relay outputs. This integration eliminates the need for additional signal modules in basic applications, significantly reducing cabinet space requirements and overall system cost. The relay outputs, rated at 2 A, can directly drive contactors, solenoid valves, and indicator lamps, making the Siemens 6ES5090-8MA00 a self-contained control solution for small to medium-scale machinery and standalone automation tasks .
Battery-Free Program Memory for Enhanced Reliability: One of the most significant advantages of the Siemens 6ES5090-8MA00 is its use of onboard EEPROM for user program storage, eliminating the annual battery replacement cycle that plagues battery-backed RAM-based CPUs. This design ensures the program is retained indefinitely without power, preventing the “BATF” (Battery Fault) LED surprises and program loss during extended outages or maintenance shutdowns . The battery-free approach also removes the risk of acid leakage in hot or humid cabinets, a common failure mode in aging legacy systems.
Superior Performance within the S5-90U Family: As the top-grade processor in the S5-90U family, the Siemens 6ES5090-8MA00 delivers the fastest instruction execution times of its product line, processing bit instructions in approximately 1.5 µs—substantially faster than the CPU 101 (~5 µs) and CPU 102 (~3.5 µs) variants . This enhanced performance ensures deterministic scan cycles, making the Siemens 6ES5090-8MA00 suitable for applications with tight timing requirements where response time is critical.
STEP 5 Programming Compatibility and Legacy Support: The Siemens 6ES5090-8MA00 is fully compatible with the classic STEP 5 programming environment (V7.x), supporting statement list (STL) and ladder logic (LAD) programming methods . For facilities with extensive S5 program libraries, this compatibility means no program rewrite is required when replacing failed units—simply download the existing program via the RS485 PG/OP interface and restore full operation. The front RS485 port supports connection to PG720/PG740 programmers or PCs equipped with a CP 5611 communication card, enabling program download, online monitoring, and forced I/O operations .
