Siemens 6ES5955-3NC13 Power Supply Unit

Reliable Power Delivery for S5-135U/155U Systems

The Siemens 6ES5955-3NC13 power supply unit delivers robust power for SIMATIC S5-135U central controllers and EU183U/185U expansion units. This module converts AC input into stable DC outputs for the backplane and field devices. Large automation systems require dependable power, and this unit provides it consistently.

Input and Output Specifications

The Siemens 6ES5955-3NC13 accepts 120V or 230V AC input with automatic adaptation or jumper selection. The unit provides a precision-regulated 5V DC output at 20A for backplane logic. Additionally, it delivers a 24V DC output at 8A for sensors and relays. Total output power typically reaches approximately 150W.

Protection Features and Reliability

This power supply incorporates comprehensive protection mechanisms for safe system operation. Overcurrent protection limits each output independently to prevent damage. Overvoltage and short-circuit protection also safeguard the connected modules. Furthermore, the unit includes thermal monitoring that reduces output during excessive temperatures. A green LED indicates normal operation, while a red LED signals faults.

Physical Design and Installation

The Siemens 6ES5955-3NC13 occupies the dedicated power slot in S5-135U and compatible racks. The unit weighs approximately 3.9 kg and features a large metal housing for effective heat dissipation. Natural convection cooling keeps the module within operating limits. Furthermore, the front panel includes clear LED status indicators for diagnostics.

System Integration and Compatibility

You can install this power supply in S5-135U central controllers and EU183U/185U expansion units. The module provides dedicated 5V logic power and 24V load power to support high-density I/O configurations. Always ensure the total backplane current does not exceed the module’s capacity. The unit operates reliably from 0°C to 60°C with proper cabinet ventilation.