Description

The Siemens 6ES5090-8MA01 is an ultra-compact programmable logic controller (PLC) from the legendary SIMATIC S5 series, designed as a fully integrated “All-in-One” automation solution. Combining CPU, power supply, digital inputs, and relay outputs within a single housing, this unit, known as the S5-90U, provides a cost-effective and space-saving control solution for simple automation tasks .

Engineered for robust and straightforward operation, the Siemens 6ES5090-8MA01 eliminates the need for a separate rack, power module, or I/O cards found in larger systems. Its built-in battery ensures that critical user programs and data are retained during power outages, while its direct DIN rail mounting and screw terminal connections allow for rapid installation and minimal wiring .

 

Application Scenarios

In a busy packaging plant, a 20-year-old filling machine halted production when its original S5-90U controller suffered a fatal failure. With no time for a complete system redesign and migration to a modern S7 PLC, the maintenance team sourced a Siemens 6ES5090-8MA01. Within hours, they swapped the unit, restored the backup program from an EPROM cartridge, and brought the line back online without requiring any changes to the existing 24V sensor and actuator wiring. This quick replacement prevented what would have been a costly, multi-day production stoppage.

The Siemens 6ES5090-8MA01 directly addresses the critical industrial pain point of obsolescence in long-running machinery. Its compact, integrated design makes it ideal for distributed control in space-constrained cabinets, controlling conveyor belts, packaging units, textile looms, printing presses, and simple process skids . For facilities still reliant on S5 technology, maintaining a stock of this controller is essential to avoid the massive expense and downtime associated with a full system overhaul, effectively serving as a “time machine” to extend the life of a legacy production line .

 

Parameters

Main Parameters	Value/Description
Product Model	6ES5090-8MA01 (S5-90U)
Manufacturer	Siemens
Product Category	Compact Controller / Mini PLC
Supply Voltage	115/230V AC
Digital Inputs	10 x 24V DC
Digital Outputs	6 x Relay Contacts
Backup Battery	Enclosed 10DE 24V (retains program during power loss)
Programming Interface	PG Port (for STEP 5)
Memory	External S5 EPROM/FEPROM storage required
Weight	Approx. 0.5 – 1.2 kg (dependent on version)
Dimensions (WxHxD)	Approx. 120mm x 105mm x 133mm
Operating Temperature	0°C to +60°C
Certification	CE, compliant with EN 61131-2

 

Technical Principles and Innovative Values

• Innovation Point 1: Ultra-High Integration “All-in-One” Architecture. The defining innovation of the Siemens 6ES5090-8MA01 is its consolidation of CPU, power supply, and basic I/O into a single compact housing . This eliminates the need for a backplane rack and multiple separate modules, dramatically reducing installation costs, cabinet space requirements, and the points of potential failure. This “Minimalist Design” philosophy makes it a uniquely economical and reliable solution for small-scale automation tasks compared to modular systems.
• Innovation Point 2: Simplified Programming and Commissioning. The Siemens 6ES5090-8MA01 supports the well-established STEP 5 programming language, which is familiar to a generation of automation engineers . Its dedicated PG port simplifies communication for programming and monitoring. With no complex hardware configuration or network setup required, the Siemens 6ES5090-8MA01 offers a significantly faster “out-of-the-box” commissioning process compared to modern controllers, a major advantage for rapid deployment and on-the-fly maintenance.
• Innovation Point 3: Legendary Ruggedness and Reliability. Built to the original industrial standards of the 1980s, the Siemens 6ES5090-8MA01 is renowned for its “tank-like” construction. It employs conservative design principles and robust components that offer high resistance to electromagnetic interference, voltage fluctuations, and harsh industrial environments without the complexity of modern operating systems . This legendary reliability often translates to a service life of two decades or more, making it a uniquely dependable component for critical, low-complexity applications .