Main Components of a PLC System: Complete Guide for Engineers
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The Siemens SITOP PSU300S 6EP1433-2BA20 is a three-phase stabilized power supply that converts a wide-range 400-500 V 3AC input into a controlled 24 V DC output rated at 5 A (120 W), with an alarm relay contact for 24 V OK status. It carries IP20 protection, 89.5 percent efficiency, and marine classification from ABS and DNV.
Choose the PSU300S over the single-phase PSU100L/PSU100S when the cabinet already carries a 3AC 400-500 V feed, since running from three phases instead of splitting a single-phase load reduces neutral current and lets the supply hold a wider -25 to +70 C ambient range. The 150 percent overload capability for up to 5 s/min covers brief inrush from contactors or solenoids on the 24 V bus without oversizing the unit. ABS and DNV marine classification, combined with the -25 to +70 C rating, make this the variant to pick for shipboard or offshore panel builds rather than the standard PSU300S without marine approval.
Supplies 24 V DC control power from a 3-phase 400-500 V feed in control cabinets, marine and offshore electrical panels, and industrial plants already wired for 3AC distribution at the control-power level.
| product brand name | SITOP |
|---|---|
| product type designation | PSU300S |
| product designation | Power supply SITOP smart |
| type of current supply | 24 V/5 A |
| type of the power supply network | 3-phase AC |
|---|---|
| phase number | 3 |
| voltage curve at input | AC |
| supply voltage at AC: minimum rated value | 400 V |
| supply voltage at AC: maximum rated value | 500 V |
| supply voltage at AC: initial value | 340 V |
| supply voltage at AC: full-scale value | 550 V |
| supply voltage: at 50 Hz | 400 V |
| supply voltage: at 60 Hz | 500 V |
| line frequency | 50/60 Hz |
| wide range input | Yes |
| buffering time for rated value of the output current in the event of power failure minimum | 18 ms |
| operating condition of the mains buffering | at Vin = 400 V |
| input current: at rated input voltage 400 V | 0.45 A |
| input current: at rated input voltage 500 V | 0.4 A |
| current limitation of inrush current at 25 °C maximum | 20 A |
| I2t value maximum | 0.5 A2·s |
| fuse protection type | none |
| fuse protection type in the feeder | Required: 3-pole connected miniature circuit breaker 3 ... 16 A characteristic C or circuit breaker 3RV2011-1DA10 (setting 3 A) or 3RV2711-1DD10 (UL 489- listed, DIVQ) |
| voltage curve at output | Controlled, isolated DC voltage |
|---|---|
| product function output voltage controlled | Yes |
| product function output voltage stabilized | Yes |
| output voltage at DC rated value | 24 V |
| output voltage: at output 1 at DC rated value | 24 V |
| output voltage: at output 1 at DC | 24 V |
| output voltage adjustable | Yes; via potentiometer |
| adjustable output voltage | 24 ... 28 V; max. 120 W |
| relative overall tolerance of the voltage | 3% |
| relative control precision of the output voltage: on slow fluctuation of input voltage | 0.1 % |
| residual ripple: maximum | 200 mV |
| voltage peak: maximum | 240 mV |
| display version for normal operation | Green LED for 24 V OK |
| type of signal at output | Relay contact (NO contact, rating 60 V DC/ 0.3 A) for "24 V OK" |
| behavior of the output voltage when switching on | Overshoot of Vout < 5 % |
| response delay maximum | 1.5 s |
| voltage increase time of the output voltage: typical | 60 ms |
| voltage increase time of the output voltage: maximum | 500 ms |
| output current: rated value | 5 A |
| output current: rated range | 0 ... 5 A; 6 A up to +45°C; +60 ... +70 °C: Derating 5%/K |
| supplied active power typical | 120 W |
| bridging of equipment | Yes |
| number of parallel-switched equipment resources for increasing the power | 2 |
| Part number | 6EP1433-2BA20 |
|---|---|
| Type designation | PSU300S |
| Brand | Siemens |
| Condition | New, factory sealed |
| Source | Siemens and its authorised distributors |
| Warranty | Manufacturer warranty |
| Lifecycle status | Active, in production |
| EAN | 4025515154037 |
| ETIM class | EC002540 |
| eCl@ss | 27040701 |
| efficiency in percent | 89.5 % |
|---|---|
| power loss [W]: at rated output voltage for rated value of the output current typical | 14 W |
| relative control precision of the output voltage with rapid fluctuation of the input voltage by +/- 15% typical | 1% |
|---|---|
| relative control precision of the output voltage load step of resistive load 50/100/50 % typical | 1% |
| setting time: load step 50 to 100% typical | 3 ms |
| setting time: load step 100 to 50% typical | 3 ms |
| relative control precision of the output voltage at load step of resistive load 10/90/10 % typical | 3% |
| setting time: load step 10 to 90% typical | 4 ms |
| setting time: load step 90 to 10% typical | 4 ms |
| setting time: maximum | 10 ms |
| design of the overvoltage protection | protection against overvoltage in case of internal fault Vout < 35 V |
|---|---|
| property of the output short-circuit proof | Yes |
| design of short-circuit protection | Constant current characteristic |
| typical | 6.6 A |
| overcurrent overload capability: in normal operation | overload capability 150 % Iout rated up to 5 s/min |
| enduring short circuit current RMS value: maximum | 8 A |
| galvanic isolation between input and output | Yes |
|---|---|
| galvanic isolation | Output voltage: SELV, ES1 (IEC 62368-1), DVC As (IEC 61204-7) |
| operating resource protection class | Class I |
| protection class IP | IP20 |
| standard: for emitted interference | EN 55022 Class B |
|---|---|
| standard: for mains harmonics limitation | EN 61000-3-2 |
| standard: for interference immunity | EN 61000-6-2 |
| certificate of suitability: CE marking | Yes |
|---|---|
| certificate of suitability: UL approval | Yes; cULus-Listed (UL 508, CSA C22.2 No. 107.1), File E197259 |
| certificate of suitability: UKCA marking | Yes |
| certificate of suitability: EAC approval | Yes |
| certificate of suitability: NEC Class 2 | No |
| type of certification: BIS | Yes; R-41183539 |
| type of certification: CB-certificate | Yes |
| MTBF at 40 °C | 500 000 h |
| certificate of suitability: IECEx | No |
|---|---|
| certificate of suitability: ATEX | No |
| certificate of suitability: ULhazloc approval | No |
| certificate of suitability: FM registration | No |
| shipbuilding approval | Yes |
|---|---|
| Marine classification association: American Bureau of Shipping Europe Ltd. (ABS) | Yes |
| Marine classification association: French marine classification society (BV) | No |
| Marine classification association: Det Norske Veritas (DNV) | Yes |
| Marine classification association: Lloyds Register of Shipping (LRS) | No |
| Environmental Product Declaration | Yes |
|---|---|
| global warming potential [CO2 eq]: total | 392.9 kg |
| global warming potential [CO2 eq]: during manufacturing | 12.9 kg |
| global warming potential [CO2 eq]: during operation | 379.6 kg |
| global warming potential [CO2 eq]: after end of life | 0.37 kg |
| ambient temperature: during operation | -25 ... +70 °C; with natural convection |
|---|---|
| ambient temperature: during transport | -40 ... +85 °C |
| ambient temperature: during storage | -40 ... +85 °C |
| environmental category according to IEC 60721 | Climate class 3K3, 5 ... 95% no condensation |
| type of electrical connection | screw terminal |
|---|---|
| at input | L1, L2, L3, PE: 1 screw terminal each for 0.05 ... 2.5 mm2 single-core/finely stranded |
| at output | +, -: 2 screw terminals each for 0.2 ... 2.5 mm2 |
| for auxiliary contacts | 13, 14 (alarm signal): 1 screw terminal each for 0.2 ... 2.5 mm2 |
| width × height × depth of the enclosure | 50 × 125 × 120 mm |
|---|---|
| installation width × mounting height | 50 mm × 225 mm |
| fastening method | Snaps onto DIN rail EN 60715 35x7.5/15 |
| DIN-rail mounting | Yes |
| S7 rail mounting | No |
| wall mounting | No |
| housing can be lined up | Yes |
| electrical accessories | Redundancy module, buffer module, selectivity module, DC UPS |
|---|---|
| mechanical accessories | Device identification label 20 mm × 7 mm, pale turquoise 3RT1900-1SB20 |
| other information | Specifications at rated input voltage and ambient temperature +25 °C (unless otherwise specified) |
|---|
| Environmental Product Declaration: global warming potential [CO2 eq] / during manufacturing | 12.9 kg |
|---|
| Net weight | 0.45 kg |
|---|---|
| Country of origin | Romania |
| Shipping weight | 0.95 kg |
| Ships from | Türkiye |
| Dispatch | 16 Nov |
| Stock | In stock |
Source: manufacturer data · Last verified: 01 Nov 2026
No documents are on file for this part yet.
Ask us for the datasheetThe rated current of PSU300S is 5 A.
The rated operational voltage of PSU300S is 400–500–24–DC V DC.
The rated motor power of PSU300S is 0.12 kW.
The tariff (HS) code on file for PSU300S is 85044083.
The EAN (GTIN) of PSU300S is 4025515154037.
PSU300S ships from Türkiye. Shipping calculated at checkout · import duties and taxes paid on arrival. Stock items are dispatched within 1–2 business days.
Master PLC system components: CPU, power supply, I/O modules, communication interfaces, and software with sizing formulas and selection tips. Shop at Stoklink.