The Siemens 6EP1333-3BA10 is a SITOP PSU200M stabilized industrial power supply designed to deliver a dependable 24 V DC / 5 A control voltage rail for automation systems. Think of it as the quiet “metabolism” of a control cabinet: PLCs, distributed I/O, sensors, relays, small valves, HMI panels, and industrial communication gear all rely on stable 24 V. When that rail is clean and consistent, everything feels normal. When it isn’t, the machine starts behaving like it’s haunted.
What makes the 6EP1333-3BA10 especially practical in real factories is its wide AC input concept with 1-phase and 2-phase operation, and its ability to handle higher mains voltages up to 500 V AC (selectable) while still providing the same regulated 24 V DC output. The device uses a selector switch to choose the supply voltage range, supporting 120…230 V AC or 230…500 V AC, with input ranges listed up to 85…264 V AC (range 1) and 176…550 V AC (range 2).
This is an important point for OEMs and maintenance teams: instead of maintaining multiple PSU variants for different plants or regions, you can often standardize on a single robust model for mixed mains environments (while still following proper wiring and local compliance rules).
Key Technical Specifications (Table)
| Parameter | Siemens 6EP1333-3BA10 Value |
|---|---|
| Product family | SITOP PSU200M |
| Rated output | 24 V DC, 5 A |
| Rated output power | Typical 120 W |
| AC input network | 1-phase and 2-phase AC |
| Selectable AC supply ranges | 120…230 V AC or 230…500 V AC (selector switch) |
| AC input voltage ranges | 85…264 V AC (range 1), 176…550 V AC (range 2) |
| Line frequency | 47…63 Hz |
| Buffering / hold-up | Minimum 25 ms at rated load (conditions specified in datasheet) |
| Output adjustment | 24…28.8 V (potentiometer) |
| Ripple and noise | Residual ripple peak-peak max 50 mV; peaks max 200 mV (20 MHz bandwidth) |
| Efficiency | Approx. 88% |
| Protection | Short-circuit proof; selectable constant-current or latching shutdown characteristic |
| Status and signaling | Green LED “24 V OK”; relay contact (NO) 60 V DC / 0.3 A for “24 V OK” |
| Operating temperature | -25…+70 °C (natural convection) |
| Degree of protection | IP20 |
| Mechanical size (W×H×D) | 70 × 125 × 121 mm |
| Weight | 0.6 kg |
| MTBF | 1,123,973 h at 40 °C |
Why this PSU matters in real control systems
1) High-voltage input flexibility for global cabinets
Many plants operate on different mains standards, and some industrial environments include 400/480/500 V supply systems. The 6EP1333-3BA10 supports two AC supply ranges (selected via switch) and can accept input up to 550 V AC in the high range.
That capability is not just “nice to have.” It can simplify spare parts, reduce engineering variants, and make retrofits less painful when a panel is moved between facilities or reused in another project.
2) Stable 24 V under changing loads
Industrial loads are rarely steady. Solenoids pull in, relays energize, motor brakes release, industrial switches boot, and current demand steps quickly. Siemens specifies dynamic behavior including load step setting times typically 2 ms (50→100% and 100→50%) and a maximum setting time of 5 ms.
Fast transient response helps prevent nuisance PLC resets or communication dropouts—those problems that waste hours because they look like software bugs but are actually power integrity issues.
3) Clean output for electronics and signal stability
The datasheet lists residual ripple peak-to-peak max 50 mV and peak noise max 200 mV (20 MHz bandwidth).
For many control components, especially communications devices and analog measurement chains, cleaner 24 V rails reduce intermittent faults and improve measurement repeatability.
4) Buffering that can save you from brief mains dips
The PSU provides a specified minimum buffering time of 25 ms at rated output current (with operating conditions defined in the datasheet).
In practical terms, this can help ride through short disturbances caused by upstream switching events, contactors, or momentary supply sags.
Protection behavior: “keep going” vs “fail loud”
In maintenance reality, a short circuit is not a theoretical event. It’s a screwdriver slip, a cable nick, a terminal whisker, a failed load, or an incorrect retrofit. Siemens describes the PSU as short-circuit proof and offers a switchable characteristic: either an approximate constant current characteristic (around 5.5 A) or latching shutdown.
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Constant-current behavior can be useful when loads have brief peaks or when you want a controlled limitation rather than a complete shutdown.
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Latching shutdown is often preferred when you want the fault to be unmistakable and persistent, forcing a deliberate intervention and making troubleshooting faster.
The PSU also provides visual diagnostics with LEDs for normal operation and overload/short-circuit conditions (including separate indications for overload and latching shutdown).
Monitoring and integration into a PLC-based system
Beyond simply generating 24 V, the 6EP1333-3BA10 includes a relay signaling contact (NO) rated 60 V DC / 0.3 A for “24 V OK.”
This can be wired to a PLC digital input so your program can distinguish between “machine stopped” and “control power unhealthy.” That distinction matters when you’re designing alarms, controlled shutdown sequences, or predictive maintenance logic.
Installation details that prevent avoidable failures (Table)
| Installation Topic | Practical Guidance from the Datasheet |
|---|---|
| Output voltage trimming | Adjustable 24…28.8 V via potentiometer |
| Terminals | Screw terminals; input L/N/PE and output +/- support 0.2…2.5 mm² (single-core or finely stranded); alarm terminals support 0.14…1.5 mm² |
| Clearance | Required spacing: 50 mm top and 50 mm bottom (left/right 0 mm) |
| Mounting | Standard rail mounting: snaps onto DIN rail EN 60715 (35×7.5/15) |
| Cabinet environment | Natural convection; operating range -25…+70 °C |
| Upstream protection | Datasheet recommends miniature circuit breaker guidance (depending on 1-phase/2-phase operation and voltage level) |
These details are not “paperwork.” They are the difference between a supply that lasts years and a supply that runs hot, derates unexpectedly, or fails in a way that looks random.
Compliance and suitability for industrial markets
The datasheet lists multiple approvals and standards support such as CE, UL/cUL (cULus Listed), CB, EAC, and even marine approvals (ABS, DNV GL), plus EMC references including EN 55022 Class B and immunity EN 61000-6-2.
If you build machines for export or for regulated customer sites, this reduces the friction of panel certification and acceptance testing.
Summary: who should choose 6EP1333-3BA10?
Choose the Siemens 6EP1333-3BA10 when you need a robust 24 V / 5 A industrial supply with a selector-based high-voltage input concept (up to 500 V AC nominal, 550 V AC range), solid transient behavior, adjustable output, clear diagnostics, and a PLC-friendly “24 V OK” relay signal.It is an especially sensible option for OEMs and factories that want to standardize on a dependable cabinet PSU across mixed mains environments.
