Siemens SITOP PSU100S Power Supply Modules – 6EP1333-2BA01

Technical Dossier

Product Details And Specifications

Siemens SITOP PSU100S Series Technical Notes

The Siemens SITOP PSU100S is a single-phase primary-switched power supply series engineered for demanding industrial environments. Deployed across chemical processing plants, nuclear facilities, oil refineries, and continuous-process manufacturing lines worldwide, the PSU100S series converts 120/230 V AC input to stabilized 24 V DC output with high efficiency and compact DIN-rail form factor. Its wide-range input (85–264 V AC), electronic overload protection, and parallel operation capability make it a standard specification in SIMATIC S7 control panels, distributed I/O cabinets, and safety-instrumented system (SIS) enclosures. The series carries UL, CE, and ATEX-relevant certifications and is compatible with SIMATIC, SINUMERIK, and SIMOTION control architectures.

The Evolution of SITOP PSU100S Architecture

The SITOP power supply family was introduced by Siemens in the early 1990s as a replacement for transformer-based linear regulators in PLC control cabinets. The first-generation SITOP units (6EP1xxx-0xxx) used analog control ICs with limited diagnostic output. The PSU100S generation introduced digital monitoring, signaling contacts, and a standardized 24 V DC / selectable current output range (2.5 A, 5 A, 10 A, 20 A). The 6EP1333-2BA01 specifically delivers 24 V DC / 5 A (120 W) and represents the mid-range workhorse of the PSU100S catalog.

Compatibility considerations: PSU100S units are mechanically and electrically interchangeable within the same current class. They interface directly with SIMATIC ET 200 distributed I/O, S7-300/400 backplane power rails, and third-party 24 V DC bus systems. The series entered the mature/end-of-active-production phase; Siemens has positioned the SITOP PSU6200 and PSU8600 as modern successors. However, PSU100S units remain in active service across installed bases with 15–25 year operational lifespans, making spare part availability a critical maintenance requirement.

SITOP PSU100S Full Catalog & Functionalities (SKU List)

The following SKUs represent the verified SITOP PSU100S product range, classified by output current rating and function:

24 V DC / 2.5 A Output (60 W)

6EP1331-2BA10: SITOP PSU100S 24V/2.5A, 1-phase, DIN rail, 60W output, standard signaling contact.
6EP1331-2BA20: SITOP PSU100S 24V/2.5A, enhanced diagnostics variant, DC OK relay output.
6EP1331-5BA10: SITOP PSU100S 24V/2.5A, ATEX Zone 2 rated variant for hazardous area installation.

24 V DC / 5 A Output (120 W)

6EP1333-2BA01: SITOP PSU100S 24V/5A, 1-phase 85–264V AC input, DIN rail, 120W, DC OK signaling contact — primary listing SKU.
6EP1333-2BA10: SITOP PSU100S 24V/5A, updated housing revision, identical electrical specification to 2BA01.
6EP1333-2BA20: SITOP PSU100S 24V/5A, with integrated buffer module interface, extended hold-up time.
6EP1333-5BA10: SITOP PSU100S 24V/5A, ATEX Zone 2 certified, 120W, for Ex-rated control panels.

24 V DC / 10 A Output (240 W)

6EP1334-2BA10: SITOP PSU100S 24V/10A, 1-phase, 240W, parallel operation capable, DC OK contact.
6EP1334-2BA20: SITOP PSU100S 24V/10A, enhanced variant with active current sharing for redundant PSU configurations.
6EP1334-5BA10: SITOP PSU100S 24V/10A, ATEX Zone 2 rated, 240W output.
6EP1334-3BA10: SITOP PSU100S 24V/10A, 3-phase 400V AC input variant for industrial three-phase distribution panels.

24 V DC / 20 A Output (480 W)

6EP1336-2BA10: SITOP PSU100S 24V/20A, 1-phase, 480W, DIN rail, parallel and redundancy operation.
6EP1336-3BA10: SITOP PSU100S 24V/20A, 3-phase 400V AC input, 480W, for high-load control cabinets.
6EP1336-2BA20: SITOP PSU100S 24V/20A, with DC OK relay and remote inhibit input for system-level power management.

Accessory & Redundancy Modules

6EP1961-2BA11: SITOP redundancy module for PSU100S, ORing diode function, 24V/40A max, prevents single-PSU failure from causing system outage.
6EP1931-2DC11: SITOP buffer module, 24V DC, capacitor-based, extends hold-up time to 100 ms at 10A load — used with PSU100S in SIS applications.

Sourcing Hard-to-Find & Obsolete SITOP PSU100S Parts

DriveKNMS maintains a dedicated inventory of PSU100S modules sourced from decommissioned control panels, factory overstock, and certified refurbishment programs. Each unit is inspected against original Siemens electrical specifications before listing. For obsolete variants including ATEX-rated units (5BA suffix) and 3-phase input models (3BA suffix), DriveKNMS operates a cross-reference sourcing program that identifies functional equivalents within the PSU100S family or recommends validated PSU6200 migration paths where direct replacement is not feasible.

Quality Control for the SITOP PSU100S Range

All SITOP PSU100S units processed by DriveKNMS undergo a structured electrical verification protocol prior to dispatch:

Input voltage sweep test: Units are energized across the full 85–264 V AC input range to verify wide-range regulation compliance.
Output voltage accuracy check: DC output is measured at no-load, 50% load, and full rated load. Acceptable tolerance: 24.0 V ±1%.
Overload and short-circuit response test: Output is shorted to verify automatic current limiting and recovery without component failure.
DC OK signaling contact verification: Relay output is confirmed to switch at the correct undervoltage threshold (typically <21 V DC).
Thermal stress test: Units are operated at 100% rated load for 30 minutes in a controlled 40°C ambient environment to verify thermal management integrity.
Insulation resistance test: 500 V DC applied between input and output terminals; minimum 100 MΩ required.
Visual and mechanical inspection: PCB, capacitors, DIN rail clip, and terminal blocks inspected for physical damage, corrosion, or prior repair evidence.

Units that do not pass all stages are quarantined and not listed for sale.