PLCs, Power Supplies & Others

Product Overview

The Siemens 6ES5951-7LB14 serves as a dedicated power supply unit for SIMATIC S5-115U and S5-115H programmable logic controllers . This module converts AC mains voltage into stable DC power for the CPU, I/O modules, and other components within the rack. Therefore, it provides essential power distribution for legacy automation systems still in operation today.

Technical Specifications

The 6ES5951-7LB14 operates with a selectable input voltage of 115V or 230V AC at 50/60 Hz . It delivers three distinct DC outputs to accommodate different module requirements. The primary +5V DC output supplies 3A to the backplane bus. Additionally, the module provides a +5.2V DC output at 1A for EPROM programming operations and a +24V DC output at 0.2A for auxiliary circuits .

Key Design Features

The 6ES5951-7LB14 features a front-panel voltage selector switch that allows users to match the input to their local mains supply . This built-in protection circuitry prevents damage from fault conditions such as short circuits or excessive current draw . Furthermore, the module includes a dedicated 5.2V output specifically designed for programming and erasing EPROM memory modules .

Application and Integration

This power supply module fits directly into the S5-115U main rack (e.g., CR700) and serves as the backbone for the entire control system . Consequently, it powers the CPU, memory modules, and all connected I/O modules within the chassis. Industries such as manufacturing, packaging, and material handling frequently rely on this module to maintain their S5-based control infrastructure. Note that this module has been discontinued but remains available through aftermarket suppliers .

Details