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The Siemens 6ES5155-3UA21 is a 21-slot rack unit designed for the Simatic S5-135/155 automation series. This centralized housing system serves as the structural and electrical backbone for industrial controllers, providing a stable, modular environment for CPU, I/O, and communication modules. It is engineered for large-scale applications in heavy industry sectors, including steel production, automotive assembly, and chemical refining. The robust mechanical design minimizes vibrational stress on internal components, while the expansive slot configuration facilitates complex, multi-processor automation tasks and simplifies maintenance through modular component accessibility.
This rack unit is intended for use in large-scale industrial automation systems requiring high-density I/O and multi-processor configurations. It is a critical component for maintaining legacy Simatic S5 control infrastructures in sectors such as chemical processing, automotive manufacturing, and heavy metal production.
| Model | 6ES5155-3UA21 |
| Product Family | Simatic S5-135/155 |
| Slot Capacity | 21 Slots |
| Bus Voltage | 5 VDC and 24 VDC |
| Max Current Rating | 40 A |
| Operating Temperature | 0 to 60 degC |
| Power Supply Compatibility | External 24 VDC input |
The rack serves as the physical and electrical mounting chassis for Siemens Simatic S5-135/155 series modules, providing the necessary backplane communication and power distribution for the controller system.
This unit is specifically designed for the S5-135/155 series. Please verify your specific controller model requirements before installation.
The backplane is rated for a maximum current of 40 A, supporting the power requirements of high-density module configurations.