Siemens 6EP1336-3BA00 (SITOP Modular / PSU8200) DIN-Rail Power Supply
When an automation cabinet is behaving strangely, the culprit is often boring: power. Brownouts, load steps, inductive kickback, inrush currents, and “mystery resets” all love a weak 24 V rail. The Siemens 6EP1336-3BA00 from the SITOP Modular family (also referenced as SITOP PSU8200) is built to make that problem disappear by delivering a regulated 24 V DC supply at up to 20 A (480 W) for industrial control systems, sensors, actuators, distributed I/O, and HMI/PLC architectures.
Unlike generic switch-mode supplies that aim for “good enough,” this unit is designed for real cabinets: it mounts directly on a 35 mm DIN rail, supports natural convection in 0 to 70 °C environments, and provides performance characteristics that matter in practice such as low ripple, fast transient response, and short overload capability to ride through load surges.
What it is?in one sentence
A single-phase AC industrial power supply that converts 120/230 V AC to a stabilized, isolated 24 V DC output at 20 A, with adjustable output voltage and cabinet-friendly diagnostics.
Why this model is commonly chosen in industrial panels
Stable 24 V for “no excuses” control power
The output is a controlled, isolated DC voltage with an overall voltage tolerance of 3% and high control precision (0.1% on slow input/load changes). That means your PLC, I/O, safety relays, and comms modules see a predictable supply even when the upstream AC line fluctuates or the load changes.
High current headroom, plus short overload capability
Rated output current is 20 A, and the supply supports short-term overload behavior that helps with real-world loads (for example, valve manifolds, contactors, and capacitive loads that momentarily demand more current). Siemens specifies short-term overload/short-circuit behavior including a typical 60 A short-circuit current during operation (25 ms) and a start-up short-circuit current around 23 A.
Low ripple for noise-sensitive electronics
For analog sensors, encoders, or measurement modules living on the same 24 V bus, ripple matters. This unit lists residual ripple at 30 mV typical (100 mV max) and voltage peaks up to 200 mV max (60 mV typical), supporting cleaner DC distribution in mixed-signal cabinets.
Hold-up time that buys you milliseconds of sanity
It provides a buffering time of at least 20 ms at 230 V input and rated output current in the event of a brief power failure. That small window can be the difference between a nuisance PLC reboot and continuous operation through short dips.
Technical specifications (core data)
| Parameter | Specification (6EP1336-3BA00) |
|---|---|
| Product family | Siemens SITOP Modular / SITOP PSU8200 |
| Input supply type | 1-phase AC |
| Rated AC input | 120 V / 230 V (selectable via wire jumper on device) |
| AC input ranges | 85–132 V (120 V range), 176–264 V (230 V range) |
| Wide-range input | No |
| Line frequency | 47–63 Hz (50/60 Hz nominal) |
| Rated output voltage | 24 V DC (isolated, regulated) |
| Output voltage adjustment | 24–28.8 V via potentiometer |
| Rated output current | 20 A |
| Output power | 480 W (typical delivered active power) |
| Efficiency | 89% |
| Power loss | 59 W (typical at rated output) |
| Residual ripple | 30 mV typical, 100 mV maximum |
| Hold-up / buffering time | 20 ms minimum (at 230 V input) |
| Inrush current limiting | 60 A max at 25 °C (with I²t max 9.9 A²·s) |
| Recommended feeder protection | 10 A miniature circuit breaker, characteristic C (per datasheet guidance) |
| Operating temperature | 0–70 °C (natural convection) |
| Connection method | Screw terminals |
| Terminal cross-sections | Input 0.2–4 mm²; Output 0.5–4 mm² (two + and two − terminals) |
| Mounting | DIN rail EN 60715 (35 × 7.5/15) |
| Dimensions (W × H × D) | 160 × 125 × 125 mm |
| Recommended spacing | Top 50 mm; Bottom 50 mm; Left/Right 0 mm |
| Net weight | 2.2 kg |
| Status indication | Green LED for “24 V OK” |
| Optional signaling | Via signaling module 6EP1961-3BA10 (per datasheet reference) |
| Accessories (examples) | Buffer module, signaling module |
Installation and commissioning notes (the stuff that prevents field headaches)
1) Input voltage selection is deliberate (not “auto-range”)
This model is not a universal wide-range input supply. It supports two AC ranges (85–132 V or 176–264 V) and requires selecting the correct range using a wire jumper on the device. In other words: set it correctly before energizing, especially in regions where 120 V and 230 V systems coexist.
2) Use the adjustable output responsibly
The output can be trimmed from 24 V up to 28.8 V using the onboard potentiometer. This is useful for compensating voltage drop over long 24 V runs, diode redundancy modules, or high-current distribution blocks. The engineering trick is to adjust just enough to maintain the required load-end voltage without overstressing downstream devices that expect “24 V nominal.”
3) Thermal layout matters at 480 W
Siemens specifies natural convection operation and recommends spacing (50 mm above and below). Even though the unit can be lined up side-by-side, leaving vertical breathing room is the cheap insurance that keeps component temperatures down and service life up.
Typical application scenarios
In modern automation cabinets, 20 A at 24 V is enough to supply a substantial control ecosystem, for example:
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PLC rack plus remote I/O segments with multiple sensor power feeds
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HMI panels, industrial Ethernet switches, and comms gateways
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Solenoid valve manifolds and small actuators where inrush current can spike
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Mixed loads combining digital electronics and moderately inductive devices
Because the unit supports stable regulation, low ripple, and short overload behavior, it’s particularly suited for systems where intermittent load steps would otherwise cause undervoltage faults or resets.
Product lifecycle note (important for procurement planning)
Some coated / variant versions in this family (for example, 6EP1336-3BA00-8AA0) have been listed as phased out/discontinued with Siemens indicating replacement products such as the SITOP PSU6200 series; Siemens support documentation states that 6EP3336-7SC00-3AX0 has been available as a replacement since February 2021.
If you are sourcing for long-term projects or standardizing a BOM, it’s smart to confirm the exact variant and availability status before locking it into a design.
Summary
The Siemens 6EP1336-3BA00 is a serious, cabinet-grade 24 V DC / 20 A DIN-rail power supply engineered for industrial automation realities: selectable 120/230 V single-phase input, regulated and adjustable 24 V output, low ripple, solid transient behavior, and practical diagnostics. For panels where uptime is worth more than the small cost difference between “industrial” and “industrial-looking,” this is exactly the kind of power supply that quietly prevents a lot of expensive drama
