6ES5185-3UA13 & 6ES5135-3UA13 Siemens SIMATIC S5 Expansion & Central Rack Set
6ES5185-3UA13 and 6ES5135-3UA13 belong to Siemens SIMATIC S5 series rack assemblies for S5-135U / S5-155U PLC systems, including central rack and expansion rack with integrated power supply and cooling fan. This rack set is used to install CPU, I/O modules, communication boards and other S5 series plug-in modules, widely applied in old chemical, metallurgy, printing and machine tool control systems.
6ES5135-3UA13 is ZG135U central basic rack with 21 slots, serving as the main backplane of S5-135U/155U controller. It can hold CPU module, power supply and multiple signal modules, providing backplane bus communication for all inserted modules. The passive backplane realizes high-speed data exchange between CPU and I/O cards, and supports module hot swapping under proper safety operation. Status LED indicators on front panel show power and bus running status for quick fault inspection.
6ES5185-3UA13 is EG185U 21-slot expansion rack, equipped with built-in power supply and cooling fan, 120/230V AC input, 5V 18A output for backplane modules. It connects to central rack via dedicated S5 expansion cable to expand total I/O capacity of the whole PLC system. The fan ensures stable heat dissipation for long-time continuous operation, suitable for cabinet installation in dusty industrial workshops. The expansion rack can be installed at a certain distance from the central unit to realize distributed local signal collection.
The rack set adopts robust metal frame structure with IP20 protection grade, working temperature range from 0℃ to 60℃. The backplane bus provides reliable parallel signal transmission for S5 modules. The whole system can process massive digital and analog signals, execute sequence control, closed-loop regulation and interlock protection for field actuators and sensors. It supports multi-point digital input/output, analog acquisition and PROFIBUS/SINEC communication modules installation.
6ES5185-3UA13 and 6ES5135-3UA13 are discontinued legacy Siemens PLC spare parts. A large number of S5-135U/155U control cabinets are still running in heavy industry sites. When the original rack or backplane fails, replacing with this matched rack set can reuse original CPU, I/O modules, wiring and S5 user program. There is no need to modify control logic or field cable layout, which greatly reduces renovation cost and shortens plant downtime. Technicians can directly transfer all modules to new rack without rewriting PLC software.
We supply fully tested 6ES5185-3UA13 and 6ES5135-3UA13 racks. Before shipment, each rack undergoes comprehensive inspection including backplane continuity test, power supply loading test, fan operation check and bus communication verification. We inspect slot contacts, backplane wiring and cooling function to guarantee stable module insertion and reliable bus transmission. All products come with 12-month warranty. Our automation technical team provides remote support for rack assembly, module installation, expansion cable wiring and fault diagnosis. Fast global shipping is available for urgent maintenance orders.
For automation maintenance engineers and system integrators, this S5 rack set is reliable spare hardware for legacy SIMATIC S5-135U/155U control systems. It keeps the original PLC control function stable, extends service life of old automation assets and avoids high-cost full PLC system migration.