Siemens SITOP PSU100S Power Supply Modules: 6EP1332-4BA00

Technical Dossier

Product Details And Specifications

Siemens SITOP PSU100S Series Technical Notes

The Siemens SITOP PSU100S series is a standardized single-phase DIN rail power supply platform deployed across heavy industrial sectors including petrochemical plants, nuclear power facilities, offshore oil & gas installations, and continuous-process refineries. Operating on 120/230 V AC input with regulated 24 V DC output, the PSU100S range is the backbone of 24 V DC bus architectures in SIMATIC S7-300, S7-400, and distributed I/O cabinets worldwide. Its compact 45 mm to 70 mm DIN rail footprint, wide-range input tolerance (85–264 V AC), and integrated output current limiting make it a reference-class component in IEC 61131-compliant control panels. The series carries UL, CE, and cULus certifications and is rated for ambient temperatures up to 60 °C, qualifying it for tropical and desert industrial environments without derating.

The Evolution of SITOP PSU100S Architecture

The SITOP power supply family was introduced by Siemens in the early 1990s as a successor to discrete transformer-rectifier assemblies. The first-generation SITOP units (6EP1xxx-0xxx) used linear regulation and were bulky by modern standards. The PSU100S designation marks the transition to switched-mode topology, introduced in the mid-2000s, which reduced heat dissipation by over 40% compared to linear predecessors and enabled the compact 45 mm single-width DIN rail form factor.

The PSU100S architecture uses a flyback converter topology with active power factor correction (PFC) on higher-current variants. Output voltage is adjustable via front-panel potentiometer (typically ±5% of 24 V DC). The series introduced the green LED status indicator and integrated output short-circuit protection with automatic restart — features that became standard across the broader SITOP portfolio.

Compatibility note: PSU100S units share the same 24 V DC output bus as the SITOP smart, SITOP modular, and SITOP select families but are not hot-swap compatible with SITOP redundancy modules (6EP1961-2BA00) without an external diode decoupling module. Engineers migrating from PSU100S to the newer SITOP PSU8600 series must account for changed terminal block pitch (5.08 mm vs. 7.62 mm) and revised DIN rail clip geometry.

SITOP PSU100S Full Catalog & Functionalities (SKU List)

The following SKUs represent the verified production and recently discontinued models within the SITOP PSU100S family. Each entry reflects a distinct output current rating or input voltage configuration.

6EP1331-4BA00: SITOP PSU100S, 1-phase, 24 V DC / 2 A output, 45 mm width, standard DIN rail mount.
6EP1332-4BA00: SITOP PSU100S, 1-phase, 24 V DC / 5 A output, 45 mm width, wide-range AC input 85–264 V, integrated output current limiting — the most widely deployed variant in S7-300 auxiliary power circuits.
6EP1333-4BA00: SITOP PSU100S, 1-phase, 24 V DC / 10 A output, 55 mm width, suitable for mid-size I/O rack power distribution.
6EP1334-4BA00: SITOP PSU100S, 1-phase, 24 V DC / 20 A output, 70 mm width, used in high-density ET 200M and ET 200S distributed I/O cabinets.
6EP1335-4BA00: SITOP PSU100S, 1-phase, 24 V DC / 40 A output, 125 mm width, parallel operation capable for redundant bus architectures.
6EP1331-4BA10: SITOP PSU100S, updated revision of 6EP1331-4BA00, 2 A, improved EMC filter, RoHS compliant.
6EP1332-4BA10: SITOP PSU100S, updated revision of 6EP1332-4BA00, 5 A, improved EMC filter, RoHS compliant — direct form-fit-function replacement.
6EP1333-4BA10: SITOP PSU100S, updated revision of 6EP1333-4BA00, 10 A, RoHS compliant, revised terminal block labeling.
6EP1334-4BA10: SITOP PSU100S, updated revision of 6EP1334-4BA00, 20 A, RoHS compliant.
6EP1335-4BA10: SITOP PSU100S, updated revision of 6EP1335-4BA00, 40 A, RoHS compliant, parallel diode module compatible.
6EP1336-4BA00: SITOP PSU100S, 1-phase, 24 V DC / 60 A output, 150 mm width, for large PLC cabinet main bus supply.
6EP1961-2BA00: SITOP redundancy module, 24 V DC / 40 A, used in conjunction with PSU100S 40 A units for 1+1 redundant power architectures.
6EP1931-2DC31: SITOP UPS module, 24 V DC buffer, compatible with PSU100S output bus for ride-through during AC interruptions up to 200 ms.
6EP1931-2DC41: SITOP UPS module, extended buffer, 24 V DC, supports PSU100S bus with capacitor-based energy storage, 500 ms ride-through.
6EP1931-2EC31: SITOP UPS module with battery, 24 V DC, for PSU100S installations requiring multi-second power hold-up in safety-critical loops.
6EP1931-2FC01: SITOP selectivity module, 4-channel, 24 V DC, used downstream of PSU100S to provide selective load protection without tripping the main supply.

Sourcing Hard-to-Find & Obsolete SITOP PSU100S Parts

Q: How is condition confirmed before quotation?
A: Available condition, photos, test records and documentation are checked according to the requested model and sourcing channel before a formal RFQ response.

Quality Control for the SITOP PSU100S Range

SITOP PSU100S units present specific test challenges due to their switched-mode topology and integrated protection circuits. DriveKNMS applies the following verification protocol to all PSU100S units prior to dispatch:

Q: How are RFQ terms confirmed?
A: Quantity, required condition, documentation needs, destination and sourcing route are confirmed during RFQ review before quotation.