Siemens 6EP3436-8SB00-0AY0 — SITOP PSU8200 24V/20A Buying Guide

By Abdullah Zahid
13 min read
Siemens 6EP3436-8SB00-0AY0 SITOP PSU8200 24V 20A DIN rail stabilized power supply for industrial automation cabinets

Siemens 6EP3436-8SB00-0AY0 SITOP PSU8200 Stabilized Power Supply, 24 V/20 A — Industrial Specs, Wiring Overview, and Selection Guide

Controls engineers specifying or replacing a 24 V DC power supply in a three-phase cabinet know the risk: choose the wrong current rating or input configuration and you are looking at a reorder, a redesign, or downtime. The Siemens 6EP3436-8SB00-0AY0 is the SITOP PSU8200 Stabilized Power Supply, 24 V/20 A — a DIN rail-mount, three-phase AC input regulated DC supply with integrated soft-start, electronic short-circuit protection, and a PROFINET interface for remote diagnostics. If you are replacing a legacy SITOP unit or specifying a standard supply for a new SIMATIC-based machine build, this is the SKU most engineers in that position land on.

If you have already confirmed this is the right part, check current pricing and availability at LeadTime.ca — ships worldwide.

Who Should Buy the 6EP3436-8SB00-0AY0 — and Who Shouldn't

This supply is the right choice for engineers who meet all of the following conditions:

  • Three-phase AC supply is available in the electrical distribution at 400–500 V rated input (operable range 320–575 V with derating)
  • Continuous DC load requirement is at or below 20 A at 24 V — not a 30 A or 40 A application
  • Cabinet uses standard TS-35 DIN rail with at least 70 mm horizontal space available for mounting
  • PROFINET or Ethernet remote diagnostics is specified or anticipated for the installation
  • CE, UL/CSA, or cCSAus certification is required for the target geography and industry
  • Unit is intended for a non-hazardous area — no ATEX or IECEx classification on the installation

If your input supply is single-phase only, look at the SITOP PSU3200 series. If your load exceeds 20 A continuous, step up to the 6EP3437-8SB00-0AY0 (30 A) or 6EP3438-8SB00-0AY0 (40 A) within the SITOP PSU8200 family. If 10 A is sufficient, the 6EP3436-8SB00-2AY0 offers a smaller footprint at lower cost.

On this page:

What the SITOP PSU8200 Actually Does in a Control Cabinet

The 6EP3436-8SB00-0AY0 is a stabilized three-phase AC to 24 V DC power supply. Its function is straightforward: it takes 400–500 V three-phase AC from your main distribution and delivers a clean, regulated 24 V DC output at up to 20 A continuous to power the logic layer of your automation system — PLC input modules, I/O terminals, solenoids, safety logic relays, and distributed control nodes. What separates this unit from a basic DIN rail supply is the combination of soft-start (no inrush overshoot), electronic short-circuit protection, and a PROFINET interface that lets your engineering team monitor supply health remotely and integrate power supply status into predictive maintenance routines.

The output voltage is adjustable from 4 to 28 V via a front-panel potentiometer or remotely via the IE/PN interface. Control precision on slow input voltage fluctuation is ±0.2% typical, and on a resistive load step (10/90/10%) it is ±0.1–0.4% typical with a maximum 10 ms setting time. Ripple is a maximum 100 mV. The unit has galvanic isolation between input and output per EN 61204-7 Safety Extra Low Voltage classification. Buffering time at rated output current is a minimum 15 ms — enough to ride through brief mains interruptions without dropping your control logic, and extendable with external BUF8600 or UPS8600 modules. An MTBF of 298,979 hours at 40°C is documented by Siemens for this series, which is the kind of reliability number a controls engineer quotes to a plant manager when justifying a specified brand over an unproven alternative.

Typical System Architecture: Where This Supply Fits

The 6EP3436-8SB00-0AY0 sits between the three-phase main distribution and the 24 V DC control bus inside your panel. It is the primary power conversion stage before your logic devices see any voltage.

  • Three-phase main distribution panel (400–500 V AC) feeds through a main circuit breaker or contactor to the supply input terminals (L1, L2, L3, PE)
  • The 6EP3436-8SB00-0AY0 converts and regulates to 24 V DC output, distributed via output terminals to a common 24 V DC bus bar or directly to load circuits
  • PLC CPU and I/O modules, safety relays, solenoid valves, HMI panels, and Ethernet switches draw from the 24 V DC bus
  • Optional CNX8600 expansion module connects to the supply for DIP-switch selectable output prioritization during mains buffering events
  • Optional BUF8600 or UPS8600 modules extend holdup time beyond the built-in 15 ms minimum for critical load continuity during mains interruptions

Industries and Applications Where This Supply Is Specified

Discrete manufacturing lines — automotive assembly, appliance production, machinery OEM builds — represent the highest-volume application for this supply. When a controls engineer standardizes on the SITOP PSU8200 family across all machine platforms, the 6EP3436-8SB00-0AY0 becomes the go-to SKU for any distributed I/O node or PLC cabinet with a 20 A 24 V requirement and a three-phase feed available.

Process automation environments in food and beverage, chemical processing, and pharmaceutical packaging specify this unit where PROFINET is already deployed at the controller level. The ability to integrate power supply diagnostics — voltage, current, fault state — into an existing PROFINET network without additional gateway hardware is the deciding factor in those installations.

Machine retrofit projects where aging SITOP PSU units reach end-of-life are another strong use case. The 70 mm DIN rail footprint and the backward-compatible SITOP PSU family mounting allow a drop-in swap without panel rework, which matters when the goal is minimizing machine downtime during a maintenance window.

UPS-backed critical control systems — where PLC safety logic must continue during a brief mains failure — use this supply as the primary conversion stage paired with an external UPS8600 or BUF8600 module. The built-in 15 ms buffering plus the external module extends holdup sufficiently for most PLC orderly-shutdown sequences.

Application Typical Deployment
Discrete manufacturing line — PLC and I/O cabinet Standard 24 V supply for SIMATIC S7 I/O modules, safety relays, solenoid banks in machine cell panel
Process automation — distributed control node Distributed panel power supply feeding ET 200 I/O stations, field instruments, and industrial Ethernet switches
Machine retrofit — legacy SITOP replacement Drop-in swap of failed or end-of-life SITOP PSU unit; same DIN rail footprint, compatible output
UPS-backed critical control system Primary conversion stage with external BUF8600 or UPS8600 module for holdup extension beyond 15 ms
OEM machine build — SIMATIC platform standard Platform-standard supply specified across all machine variants; PROFINET interface used for remote commissioning and maintenance visibility
Predictive maintenance rollout PROFINET and OPC UA interface integrated into MES or cloud monitoring platform for supply health trending

Purchase-Decision Specs: 6EP3436-8SB00-0AY0 at a Glance

Parameter Value
Input voltage (rated) 3-phase AC, 400–500 V
Input voltage (operable range) 320–575 V AC (with derating outside 400–500 V)
Output voltage (nominal / adjustable) 24 V DC / 4–28 V via potentiometer or IE/PN interface
Output current (rated) 20 A continuous (0–20 A range)
Short-circuit protection Electronic overload shutdown; max 22 A enduring short-circuit RMS; optional constant-current mode
Buffering time (minimum at rated load) 15 ms
Output ripple (maximum) 100 mV
Dimensions (W × H × D) 70 × 125 × 125 mm
Ambient temperature (operating) -25 to +70°C
Certifications CE, UL 508 / CSA C22.2 No. 107.1 (cULus / cCSAus), EAC, CB, BIS, SEMI F47, FM

Full technical specifications are available on the product page at LeadTime.ca.

SITOP PSU8200 Variant Comparison: Which Model Do You Actually Need?

Model Output Current Input Type DIN Rail Width PROFINET Best For
6EP3436-8SB00-2AY0 10 A 3-phase AC Smaller than 70 mm Yes Lower current loads; cost-sensitive applications
6EP3436-8SB00-0AY0 20 A 3-phase AC 70 mm Yes Standard 20 A 24 V control cabinet; SIMATIC platform standard
6EP3437-8SB00-0AY0 30 A 3-phase AC Wider (triple) Yes Higher current loads exceeding 20 A continuous
6EP3438-8SB00-0AY0 40 A 3-phase AC Larger enclosure required Yes Maximum current in SITOP PSU8200 family
SITOP PSU3200 series Varies Single-phase AC Varies Varies by model Installations without three-phase distribution

If your cabinet has three-phase distribution and your continuous load is exactly in the 20 A range, the 6EP3436-8SB00-0AY0 is the correct selection — check current availability at LeadTime.ca.

Expert Verdict: Honest Assessment for Engineers Who Need to Decide Now

The 6EP3436-8SB00-0AY0 earns its place as a platform-standard supply in Siemens-based automation for concrete reasons. The 298,979-hour MTBF at 40°C is a real number drawn from the official product data — not a marketing estimate — and it translates to fewer unplanned replacements in running production. The combination of soft-start with no output overshoot and electronic short-circuit protection with a maximum 22 A enduring RMS limit protects downstream PLC inputs and I/O modules from the current spikes that shorten their service life. For facilities already running PROFINET at the controller level, the built-in PROFINET and OPC UA interface on this supply closes the loop on power supply monitoring without any additional gateway hardware. The 15 ms minimum buffering also provides a practical safety net for brief mains sags that would otherwise cause nuisance resets on sensitive logic.

Where this model has real limits: it is strictly a three-phase supply. If site infrastructure is single-phase — which is common in smaller facilities, older buildings, or North American light commercial installations — this unit does not apply, and the SITOP PSU3200 series is the correct family. It also does not replace a UPS. The 15 ms built-in holdup is useful for ride-through during transients, but any application requiring extended backup power during mains failure needs an external BUF8600 or UPS8600 module added to the system — those are separate line items. Engineers who order the 6EP3436-8SB00-0AY0 expecting integrated battery backup will be disappointed. Finally, at 70 mm wide and 125 mm tall, it occupies meaningful DIN rail real estate; verify panel layout before committing in a tight cabinet redesign. If your application requires this supply, view current stock and pricing at LeadTime.ca.

On the procurement side, this is an active product with no announced discontinuation as of early 2026. Standard stock orders through authorized channels typically ship in one to two weeks; backorder or special configuration scenarios can run four to eight weeks. For facilities in North America, standard Siemens distribution channels carry this SKU. LeadTime.ca sources globally and can confirm current lead time and volume pricing before you commit to a build schedule — particularly useful when ordering ten or more units for a multi-cabinet or multi-machine project.

For volume pricing or to confirm lead time before committing to a build, contact the LeadTime.ca team directly — we ship worldwide.

Wiring and Installation Overview

  • Input terminals accept L1, L2, L3, and PE from a three-phase 400–500 V AC supply; terminal capacity is 0.2–4 mm² single-core or finely stranded wire, line frequency 47–63 Hz; rated supply must be present before output regulation is possible
  • Output terminals (24 V+, common) use the same 0.2–4 mm² terminal capacity; output voltage is adjustable from 4 to 28 V via the front-panel potentiometer (factory default 24 V), with derating applied above 24 V at 4%/V and a maximum system power cap of 480 W
  • Maintain a minimum 50 mm clearance above and below the unit for convection cooling; left and right clearance requirements are 0 mm, but do not mount adjacent to high heat-generating components such as VFDs or motor soft-starters
  • DIN rail mounting uses standard TS-35 profile; unit dimensions are 70 mm wide × 125 mm high × 125 mm deep; installation height (including clearances) is 225 mm
  • On power-up, soft-start engages with no output overshoot; output connection delay is DIP-switch selectable (simultaneous, 25 ms, 100 ms, or load-optimized sequential); maximum startup latency to full regulation is 1 second — verify downstream devices tolerate this startup window

For full wiring diagrams and step-by-step installation procedures, refer to the Siemens SITOP PSU8200 operating instructions available through the Siemens Industry Support portal.

Compatible Expansion Modules and UPS Options

The 6EP3436-8SB00-0AY0 is designed to work with the following SITOP expansion modules when the application demands more than the base supply provides:

  • CNX8600: Expansion module that enables DIP-switch selectable mains buffering priority — required if you want to configure output prioritization during brief mains failure via the front DIP switches on the main supply
  • BUF8600: External capacitive buffer module that extends holdup time beyond the built-in 15 ms minimum at rated output current; used for short-duration mains interruption ride-through in critical control systems
  • UPS8600: External battery-backed UPS module for extended supply continuity during mains loss; the correct choice when PLC or safety logic must remain powered for more than a capacitive buffer can provide

None of these modules are included with the base 6EP3436-8SB00-0AY0 — they are separate line items and must be ordered and configured independently. If your application requires UPS backup, confirm the UPS8600 or BUF8600 is on your BOM before the panel ships.

Wrong-Part Prevention Checklist Before You Order

Run through these six checks before finalizing your purchase order for the 6EP3436-8SB00-0AY0:

  1. Confirm three-phase AC supply is available in your electrical distribution; single-phase models are not cross-compatible.
  2. Verify rated input voltage is 400–500 V (or 320–575 V acceptable range); 230 V single-phase or 277 V North American single-phase do NOT match.
  3. Check that 20 A continuous current output is sufficient; do not assume this model suits 30+ A loads without derating calculations.
  4. Confirm DIN rail mounting is supported in your enclosure; some older panels may use frame or bolt-down only.
  5. If PROFINET remote control is required, ensure your controller supports Ethernet and PROFINET protocol; this model has the interface, but network configuration is your responsibility.
  6. Verify UPS backup is NOT required on this unit alone; external buffer/UPS modules (BUF8600, UPS8600) must be ordered separately.

If all six checks pass, proceed to the product page at LeadTime.ca to confirm stock and request a quote. If any check raises a flag, contact the LeadTime.ca team and we will help identify the correct variant.

Frequently Asked Questions

Can the 6EP3436-8SB00-0AY0 operate on a 480 V three-phase North American supply?

Yes. The operable input voltage range is 320–575 V AC, which covers the 480 V nominal three-phase supply common in North American industrial facilities. Derating applies outside the 400–500 V rated range, so verify that your actual continuous load does not exceed the derated output capacity at 480 V input. Consult the Siemens SITOP PSU8200 derating curves in the product documentation for exact figures.

What happens when the output is short-circuited — does the unit latch off permanently?

The unit triggers an electronic overload shutdown and the red LED illuminates as a latching fault indicator. The 6EP3436-8SB00-0AY0 does not auto-recover while the short persists. Once the fault condition is cleared, recovery is via a remote reset signal (signal level above 15 V at the sensor input) or via the PROFINET interface — or by removing and reapplying mains power. An optional constant-current mode can be configured where the unit instead reduces output to approximately 22 A continuous rather than hard-shutting down.

Is the built-in PROFINET interface sufficient for integration into a TIA Portal project, or is additional hardware required?

The PROFINET and Ethernet interface is built into the 6EP3436-8SB00-0AY0 with OPC UA support, so no additional gateway module is required for basic PROFINET integration. You will need to assign a unique IP address via TIA Portal or a PROFINET configuration tool and configure cyclic data exchange. The CNX8600 expansion module is only needed if you require DIP-switch selectable mains buffering priority — not for PROFINET communication itself.

What is the realistic lead time for this supply, and what are the options if stock is not available?

Standard availability is one to two weeks for in-stock orders through authorized distributors. Backorder or special configuration scenarios typically run four to eight weeks. If lead time is critical, LeadTime.ca can confirm current stock status globally. Alternative options while awaiting supply include the Phoenix Contact QUINT POWER 24/20 (similar specifications) or temporary use of a unit from industrial surplus channels — though warranty and certification status should be verified for surplus units in regulated industries.

Does this supply meet NEC Class 2 output requirements?

No. The 6EP3436-8SB00-0AY0 does not carry NEC Class 2 certification. It holds CE, UL 508, CSA C22.2 No. 107.1 (cULus and cCSAus listed), EAC, CB, BIS, SEMI F47, and FM approvals, but NEC Class 2 is explicitly not included. If NEC Class 2 output is a hard requirement for your installation (common in certain building automation or low-voltage wiring applications), you will need to specify a different supply or add a Class 2 isolating transformer on the output circuit.

Can output voltage be adjusted above 24 V for cable-run compensation, and is there a power limit above 24 V?

Yes, the output voltage is adjustable from 4 to 28 V via the front-panel potentiometer or remotely via the IE/PN interface. Above 24 V, output power is derated at 4% per additional volt, and the maximum system power cap is 480 W regardless of voltage setting. For most 24 V control system applications this is not a constraint, but verify the derating does not reduce available current below your load requirement if you are tuning above 24 V for long cable runs.

Why Order from LeadTime.ca

  • Ships worldwide — no regional restriction on orders; sourcing support for customers across North America, Europe, Asia-Pacific, and beyond
  • Real-time stock confirmation before you commit to a build schedule — contact us to verify availability on the 6EP3436-8SB00-0AY0 and any associated expansion modules
  • Volume pricing available for multi-unit orders (10+ units typical threshold for discount discussion)
  • Hard-to-find and long lead-time industrial automation parts sourced through global distribution relationships
  • Fast response on RFQs — procurement specialists and controls engineers contact us for quote turnaround before project deadlines

At-a-Glance Summary

  • Model: Siemens 6EP3436-8SB00-0AY0 — SITOP PSU8200 Stabilized Power Supply, 24 V/20 A
  • Input: Three-phase AC, 400–500 V rated; operable range 320–575 V with derating
  • Output: 24 V DC nominal, adjustable 4–28 V; 20 A continuous rated; max 22 A enduring short-circuit RMS
  • Ripple: Maximum 100 mV; control precision ±0.2% on slow input fluctuation; ±0.1–0.4% on load step
  • Buffering: Minimum 15 ms at rated output current; extendable with BUF8600 or UPS8600 modules
  • Communications: PROFINET, Ethernet, OPC UA built in; DIP-switch selectable output prioritization (requires CNX8600)
  • Dimensions: 70 × 125 × 125 mm; 1.8 kg; TS-35 DIN rail mount; IP20 Class I
  • Operating temperature: -25 to +70°C; transport/storage -40 to +85°C
  • Certifications: CE, UL 508 / CSA C22.2 No. 107.1 (cULus / cCSAus), EAC, CB, BIS (R-41188271), SEMI F47, FM; not ATEX / IECEx / NEC Class 2
  • MTBF: 298,979 hours at 40°C
  • Status: Active product; standard lead time 1–2 weeks from stock; available worldwide through LeadTime.ca