Description
The Siemens 6ES5095-8MA04 is a compact central unit (CPU) from the SIMATIC S5-95U series, designed as an integrated controller for small to medium-sized automation tasks . This all-in-one module combines the processor, power supply, and basic I/O in a single compact housing, eliminating the need for a separate rack.
The 6ES5095-8MA04 serves as the core of the SIMATIC S5-95U system, executing user programs written in STEP 5 languages (STL, LAD, or CSF) and managing all control, monitoring, and communication functions . This central unit is specifically designed for space-constrained applications where a modular rack system would be impractical, offering a cost-effective solution for simple to moderately complex automation tasks.
Application Scenarios
At a mid-sized packaging machinery manufacturer, an aging S5-95U controller failed on a critical shrink-wrap line, threatening a production halt. The facility’s maintenance team quickly sourced a Siemens 6ES5095-8MA04 as a drop-in replacement. Within minutes of installation, the machine was back online, with the 6ES5095-8MA04 executing the existing program without modification. This rapid restoration saved an estimated $20,000 in lost production and demonstrated the value of maintaining legacy S5 spares.
In a building automation context, a facility manager needed to upgrade an obsolete S5-90U system controlling HVAC across a large office complex. The 6ES5095-8MA04 provided a direct upgrade path, offering increased processing speed and expanded memory capacity while maintaining compatibility with existing wiring and peripheral devices . The Siemens 6ES5095-8MA04 now reliably manages 32 digital inputs/outputs and analog signals across the building’s climate control system.
Parameters
| Main Parameters | Value/Description |
|---|---|
| Product Model | 6ES5095-8MA04 |
| Manufacturer | Siemens |
| Product Category | Compact Central Unit (CPU) / SIMATIC S5-95U Series |
| Power Supply Voltage | 24 V DC |
| Processor Type | 16-bit |
| Memory | Program and data memory via expansion submodules |
| Integrated I/O | Digital and analog (limited) |
| Programming Languages | STEP 5 (STL, LAD, CSF) |
| Communication Interface | 20 mA current loop (standard) |
| Optional Communication | PROFIBUS DP slave interface |
| Operating Temperature | 0°C to +60°C (horizontal installation) |
| Protection Class | IP20 |
| Mounting Type | DIN rail / Panel mount |
| Weight | Approx. 1.2 – 1.3 kg |
Technical Principles and Innovative Values
Innovation Point 1: All-in-One Compact Architecture
The Siemens 6ES5095-8MA04 integrates the CPU, power supply, and basic I/O into a single unit, eliminating the need for a separate rack and backplane . This compact design reduces cabinet space requirements by up to 50% compared to modular S5 systems, making it ideal for small machinery and distributed control applications.
Innovation Point 2: Cyclic Program Execution with Watchdog Protection
The 6ES5095-8MA04 operates on a cyclic principle: reading inputs, executing the user program, and writing outputs—all under the supervision of an integrated watchdog timer . This ensures the system enters a safe state if the program execution exceeds the maximum cycle time, preventing uncontrolled machine operation. The typical basic logic instruction execution time is approximately 1.5 µs .
Innovation Point 3: Flexible Programming and Communication
The Siemens 6ES5095-8MA04 supports multiple programming methods (STL, LAD, CSF) and sequential control programming via GRAPH Mini . The standard 20 mA current loop interface enables connection to programming devices and operator panels, while optional PROFIBUS DP slave capability allows integration into larger distributed automation networks
