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VSK-S20-3R3U-T
ENCLOSED AC-DC CONVERTERS POWER SUPPLIES
⚠️ Reference pricing provided. In case of supply shortages, we will connect you with our trusted procurement partners to ensure your project's continuity.
- Manufacturer: BEL / PARTNER STOCK
- Product type: AC / DC Enclosed Power Supplies
- SVHC: To Be Advised
- Product Range: VSK-S20 Series
| Delivery and price | |
|---|---|
| Units per pack | 9 |
| Price | 37.76 € |
| Current stock | 25+ |
| Lead time | 30 days |
Datasheet
|Additional Resources:Product Page||| |---|---|---| |GY Culinc|**date**<br>**page**|10/29/2020<br>1 of 7| |**SERIES:**VSK-S20-T**DESCRIPTION:**AC-DC POWER SUPPLY<br>**MODEL**<br>**output**<br>**voltage**<br>**output**<br>**current**<br>**output**<br>**power**<br>**ripple**<br>**and noise1**<br>(Vdc)<br>**max**<br>(A)<br>**max**<br>(W)<br>(mVp-p)<br>(%)<br>VSK-S20-3R3U-T<br>3.3<br>4.1<br>13.5<br>50<br>74<br>VSK-S20-5U-T<br>5<br>3.5<br>17.5<br>50<br>78<br>VSK-S20-9U-T<br>9<br>2.1<br>20<br>50<br>80<br>VSK-S20-12U-T<br>12<br>1.6<br>20<br>50<br>82<br>VSK-S20-15U-T<br>15<br>1.3<br>20<br>50<br>83<br>VSK-S20-24U-T<br>24<br>0.85<br>20<br>50<br>85<br>Notes:<br>1. Ripple and noise are measured at 20 MHz BW by “parallel cable” method with 1 uF ceramic and 10 uF electrolytic capacitors on the output.<br>**FEATURES**<br>• up to 20W continuous power<br>• compact chassis mount design<br>• universal input (85~264 Vac / 100~370 Vdc)<br>• single, regulated output from 3.3~24 Vdc<br>• over voltage, over current, and short circuit protections<br>• UL/cUL safety approvals<br>• efficiency up to 85%<br>**PART NUMBER KEY**<br>**VSK-S20- XXU - T**<br>Base Number<br>Output Voltage<br>DISCONTI UED<br>rowsCOAL<br>C €||| |**cui**.com||| Additional Resources: Product Page **CUI Inc � SERIES:** VSK-S20-T **� DESCRIPTION:** AC-DC POWER SUPPLY **date** 10/29/2020 **� page** 2 of 7 ## **INPUT** ||**parameter**<br>**conditions/description**<br>**min**<br>**���**<br>**max**<br>**units**<br>voltage<br>85<br>100<br>264<br>370<br>Vac<br>Vdc<br>frequency<br>47<br>63<br>Hz<br>current<br>at 115 Vac<br>at 230 Vac<br>600<br>340<br>mA<br>mA<br>inrush current<br>at 115 Vac<br>at 230 Vac<br>16<br>30<br>A<br>A<br>leakage current<br>at 230 Vac, 50 Hz (RMS)<br>0.1<br>mA<br>input fuse<br>3.15 A/250 V, slow-blow type (included on chassis)<br>**OUTPUT**<br>**parameter**<br>**conditions/description**<br>**min**<br>**���**<br>**max**<br>**units**<br>capacitive load<br>3.3 Vdc output model<br>5 Vdc output model<br>9 Vdc output model<br>12 Vdc output model<br>15 Vdc output model<br>24 Vdc output model<br>48,000<br>12,000<br>7,200<br>5,400<br>2,700<br>1,800<br>��<br>��<br>��<br>��<br>��<br>��<br>line regulation<br>at full load<br>±0.5<br>%<br>load regulation<br>at 10~100% load<br>±1<br>%<br>voltage set accuracy<br>±2<br>%<br>adjustability<br>±10<br>%<br>hold-up time<br>at 115 Vac<br>at 230 Vac<br>15<br>80<br>ms<br>ms<br>switching frequency<br>65<br>kHz<br>��������������������<br>±0.02<br>%/°C<br>**PROTECTIONS**<br>**parameter**<br>**conditions/description**<br>**min**<br>**���**<br>**max**<br>**units**<br>over current protection<br>auto restart<br>110<br>%<br>short circuit protection<br>continuous, auto restart<br>over voltage protection<br>3.3 Vdc output model<br>5 Vdc output model<br>9 Vdc output model<br>12 Vdc output model<br>15 Vdc output model<br>24 Vdc output model<br>7.5<br>7.5<br>12<br>20<br>20<br>30<br>Vdc<br>Vdc<br>Vdc<br>Vdc<br>Vdc<br>Vdc<br>**SAFETY & COMPLIANCE**<br>**parameter**<br>**conditions/description**<br>**min**<br>**���**<br>**max**<br>**units**<br>isolation voltage<br>input to output for 1 minute<br>input to ground for 1 minute<br>3,000<br>2,000<br>Vac<br>Vac<br>safety approvals<br>UL60950-1, CE<br>safety class<br>class I<br>conducted emissions<br>CISPR22/EN55022, Class B<br>radiated emissions<br>CISPR22/EN55022, Class B<br>ESD<br>IEC/EN61000-4-2 Class B, contact ±6 kV/air ±8 kV<br>radiated immunity<br>IEC/EN61000-4-3 Class A, 10V/m<br>EFT/burst<br>IEC/EN61000-4-4 Class B, ±2 kV<br>�������������������������������������������������������������<br>DISCONTINUED| |---|---| ||radiated immunity| ||EFT/burst| **cui** .com Additional Resources: Product Page **CUI Inc � SERIES:** VSK-S20-T **� DESCRIPTION:** AC-DC POWER SUPPLY **date** 10/29/2020 **� page** 3 of 7 ## **SAFETY & COMPLIANCE (CONTINUED)** **==> picture [590 x 667] intentionally omitted <==** **----- Start of picture text -----**<br> parameter conditions/description min ��� max units<br>IEC/EN61000-4-5 Class B, ±1 kV/±2 kV<br>surge<br>�����������������������������������������������������������������������������<br>conducted immunity IEC/EN61000-4-6 Class A, 10 Vr.m.s<br>PFM IEC/EN61000-4-8 Class A, 10 A/m<br>voltage dips & interruptions IEC/EN61000-4-11 Class B, 0%-70%<br>MTBF as per MIL-HDBK-217F at 25°C 300,000 hrs<br>RoHS 2011/65/EU<br>ENVIRONMENTAL<br>parameter conditions/description min ��� max units<br>operating temperature see derating curves -40 70 °C<br>storage temperature -40 105 °C<br>storage humidity non-condensing 95 %<br>DERATING CURVES<br>load vs. ambient temperature load vs. input voltage (Vac) load vs. input voltage (Vdc)<br>(at 100~240 Vac) (at 25°C) (at 25°C)<br>100 100 100<br>80<br>75 75<br>60 60 60<br>Safe operating area Safe operating area Safe operating area<br>40 40 40<br>20 20 20<br>-40 -10 -5 5 25 35 45 55 65 70 75 85 95 100 105 115 125 235 240245 255 264 100 120 340 370<br>Ambient Temperature (°C) Input Voltage (Vac) Input Voltage (Vdc)<br>cui .com<br>DISCONTINUED<br>~~ ~~ ~~<br>Load (%) Load (%) Load (%)<br>~~ ~~ ~~<br>**----- End of picture text -----**<br> Additional Resources: Product Page **date** 10/29/2020 **page** 4 of 7 **CUI Inc SERIES:** VSK-S20-T **DESCRIPTION:** AC-DC POWER SUPPLY ## **MECHANICAL** |**parameter**<br>dimensions<br>case material<br>weight<br>cooling<br>**MECHANICAL DRAWING**|**conditions/description**<br>96.10 x 54.00 x 32.00 (3.783 x 2.126 x 1.259 inch)<br>UL94V-0<br>convection cooling<br>**MECHANICAL DRAWING**|**min**|170|**max**<br>**units**<br>mm<br>g<br>D| |---|---|---|---|---| units: mm[inches] tolerance: ±0.50[±0.020] ## wire range: 24~12 AWG **PIN CONNECTIONS** ~~——_—¢~~ PIN FUNCTION 1 GND 2 AC(N) ~~FF~~ 3 AC(L) 4 -Vo ~~I~~ L_] 9 5 NC ~~————J~~ i 6 TRIM Top View 7 NC ~~I~~ 8 +Vo ~~I~~ | | | | Side View **cui** .com Additional Resources: Product Page **CUI Inc � SERIES:** VSK-S20-T **� DESCRIPTION:** AC-DC POWER SUPPLY **date** 10/29/2020 **� page** 5 of 7 ## **TYPICAL APPLICATION CIRCUIT** ||**AC(L)**<br>**+Vo**<br>**-Vo**<br>**AC(L)**<br>**AC(N)**<br>**AC(N)**<br>**C1**<br>**C2**<br>**TVS1**<br>**LOAD**<br>**FUSE**<br>**AC/DC**<br>**MOV1**<br>Recommended External Circuit Components<br>MODEL<br>FUSE1<br>MOV1<br>C1<br>C2<br>TVS<br>VSK-S20-3R3U-T<br>3.15A/250V<br>S14K350<br>1µF<br>�����<br>SMBJ7.0A<br>VSK-S20-5U-T<br>3.15A/250V<br>S14K350<br>1µF<br>�����<br>SMBJ7.0A<br>VSK-S20-9U-T<br>3.15A/250V<br>S14K350<br>1µF<br>�����<br>SMBJ12A<br>VSK-S20-12U-T<br>3.15A/250V<br>S14K350<br>1µF<br>�����<br>SMBJ20A<br>VSK-S20-15U-T<br>3.15A/250V<br>S14K350<br>1µF<br>�����<br>SMBJ20A<br>VSK-S20-24U-T<br>3.15A/250V<br>S14K350<br>1µF<br>�����<br>SMBJ30A<br>Recommended External Circuit Components<br>MOV1<br>S14K350<br>CY1, CY2<br>1000pF/400Vac<br>CX<br>������������<br>LCM<br>10mH<br>LDM<br>��������<br>**EMC RECOMMENDED CIRCUIT**<br>Note:<br>Also refer to Table 1<br>**Figure 1**<br>**Table 1**<br>**Figure 2**<br>**Table 2**<br>**ACDC**<br>**AC(N)**<br>**AC(L)**<br>**LCM**<br>**MOV1**<br>**CX**<br>**CY1**<br>**CY2**<br>**FUSE**<br>**AC(N)**<br>**AC(L)**<br>**+Vo**<br>**-Vo**<br>+<br>**LDM**<br>**C1**<br>**C2**<br>**TVS1**<br>**RL**<br>Note:<br>1. Fuse included on chassis<br>DISCONTINUED|**AC(L)**<br>**AC(N)**<br>|**AC(L)**<br>**AC(N)**<br>|**AC(L)**<br>**AC(N)**<br>|**AC(L)**<br>**AC(N)**<br>|**Figure 1**<br>|**Figure 1**<br>|**Figure 1**<br>|**Figure 1**<br>|**Figure 1**<br>|**Figure 1**<br>|**Figure 1**<br>|**Figure 1**<br>|**Figure 1**<br>|**Figure 1**<br>|**Figure 1**<br>|**Figure 1**<br>|**Figure 1**<br>|**Figure 1**<br>|**Figure 1**<br>|**Figure 1**<br>|**Figure 1**<br>| |---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---|---| ||||||**(L)**<br>**(N)**<br>|**FUSE**<br>|||||**+Vo**<br>**-Vo**<br>**AC(L)**<br>**AC(N)**<br>**AC/DC**<br>|||||**C1**<br>**C2**<br>**TVS1**<br>||||||| |||||||**MOV1**<br>||||||||||||||||| |||||||||||||||||||||||| |||||||||||||||||||||||| |||||||**Table 1**<br>||||||||||||||||| |||||||Recommended External Circuit Components<br>||||||||||||||||| |||MODEL<br>|||||FUSE1<br>|||MOV1<br>||||C1<br>||||C2<br>|TVS<br>|||| |||VSK-S20-3R3U-T<br>|||||3.15A/250V<br>|||S14K350<br>||||1µF<br>||||�����<br>|SMBJ7.0A<br>|||| |||VSK-S20-5U-T<br>|||||3.15A/250V<br>|||S14K350<br>||||1µF<br>||||�����<br>|SMBJ7.0A<br>|||| |||VSK-S20-9U-T<br>|||||3.15A/250V<br>|||S14K350<br>||||1µF<br>||||�����<br>|SMBJ12A<br>|||| |||VSK-S20-12U-T<br>|||||3.15A/250V<br>|||S14K350<br>||||1µF<br>||||�����<br>|SMBJ20A<br>|||| |||VSK-S20-15U-T<br>|||||3.15A/250V<br>|||S14K350<br>||||1µF<br>||||�����<br>|SMBJ20A<br>|||| |||VSK-S20-24U-T<br>|||||3.15A/250V<br>|||S14K350<br>||||1µF<br>||||�����<br>|SMBJ30A<br>|||| |||||||||N||||||||||||||| ||**AC(N)**<br>**AC(L)**<br>DI|||||||**Figure 2**<br>||||||||||||||| ||||**)**<br><br>|**FUSE**<br>||||**LCM**<br><br>**CX**<br>**LDM**<br>|||||||||**ACDC**<br>**AC(N)**<br>**AC(L)**<br>**+Vo**<br>**-Vo**<br>|||**C1**<br>**C2**<br>**TVS1**<br>**RL**<br>||| |||||**M**<br>|||**OV1**<br>|||||||**CY1**<br>**CY2**<br>|||||||+<br>|| |||||||||||||||**CY2**<br>||||||||| |||||||||||||||||||||||| |||||||||||||||||||||||| |||||||||||||||||||||||| |||||||||**Table 2**<br>||||||||||||||| |||||||||Recommended External Circuit Components<br>||||||||||||||| |||||||||MOV1<br>|||||S14K350<br>|||||||||| |||||||||CY1, CY2<br>|||||1000pF/400Vac<br>|||||||||| |||||||||CX<br>|||||������������<br>|||||||||| |||||||||LCM|||||10mH|||||||||| |||||||||LDM|||||��������|||||||||| ||||||||No|te:<br>Also refer to Table 1||||||||||||||| **cui** .com Additional Resources: Product Page **date** 10/29/2020 **page** 6 of 7 **CUI Inc SERIES:** VSK-S20-T **DESCRIPTION:** AC-DC POWER SUPPLY ## **APPLICATION NOTES** **==> picture [281 x 150] intentionally omitted <==** **----- Start of picture text -----**<br> Formula for Trim Resistor<br>aR 2 Vref<br>up: R T= R2-a -R3 a=Vo’ - Vref R 1<br>down : R T= aRR1-a 1 -R3 a=VoVref’ - Vref R 2<br>ED<br>**----- End of picture text -----**<br> 1. **Output voltage trimming** Leave open if not used. ## **Figure 3** Application Circuit for Trim pin (part in broken line is the interior of models) ||+Vo<br>R1<br>Vre f|+Vo<br>R1<br>Vre f|R3<br>Trim<br>R1<br>R3<br>Vref<br>RT<br>Trim<br>+Vo<br>aR 2<br>-a<br>R 22<br>aRR1-a 1R1-a 11<br>R2-a2-a<br>-a 1<br>RR1-a 11-a 1<br>-R33<br>-R33<br>:<br>a=Vo’ - Vref<br>Vref<br>Vref’<br>Vo’ - Vref<br>VoVref’’ - VrefVref<br>R1<br>R =<br>T=<br>:<br>a=VoVref’<br>R2<br>R =<br>T=<br>up:<br>down<br>ED| |---|---|---|---| |||R2|Note: Value for R1, R2, R3, and Vref refer to Table 3<br>RT: Trim Resistor<br>RT<br>R2| ||||Vo': The trim up/down voltage| ||0V||0V| |**Table 3**<br>Vout<br>(Vdc)<br>R1<br>R2<br>R3<br>Vref<br>(V)<br>3.3<br>3.3<br>1.98<br>1<br>1.24<br>5<br>3.3<br>3.3<br>1<br>2.5<br>9<br>7.5<br>2.87<br>1<br>2.5<br>12<br>3.83<br>1<br>1<br>2.5<br>15<br>7.5<br>1.5<br>1<br>2.5<br>24<br>8.66<br>1<br>1<br>2.5<br>Trim up<br>Trim down<br>DISCONT|||| |Notes:||1.|Output filtering capacitor C2 is an electrolytic capacitor, It is recommended to use high frequency and low impedance electrolytic capacitors. For capacitance| ||||of capacitor please refer to manufacture’s datasheet. Voltage derating of capacitor should be 80% or above. C1 is used to filter high frequency noise.| |recommended component to protect post-circuits (when converter fails).|recommended component to protect post-circuits (when converter fails).|recommended component to protect post-circuits (when converter fails).|recommended component to protect post-circuits (when converter fails).| |||2.|2.<br>AllspecificationsmeasuredatTa=25C,humidity<75%,nominalinputvoltage,andratedoutputload,unlessotherwisespecified.| Note: Value for R1, R2, R3, and Vref refer to Table 3 RT: Trim Resistor **cui** .com Additional Resources: Product Page **CUI Inc SERIES:** VSK-S20-T **DESCRIPTION:** AC-DC POWER SUPPLY **date** 10/29/2020 **page** 7 of 7 **REVISION HISTORY rev. description date** 1.0 initial release 09/06/2012 1.01 updated spec 01/08/2014 1.02 updated operating and storage temperatures, updated spec 06/11/2015 1.03 company logo updated 10/29/2020 The revision history provided is for informational purposes only and is believed to be accurate. **Headquarters** 20050 SW 112th Ave. Fax 503.612.2383 <F CUIINC Tualatin, OR 97062 **cui** .com a bel group **800.275.4899** techsupport@cui.com CUI offers a two (2) year limited warranty. Complete warranty information is listed on our website. CUI reserves the right to make changes to the product at any time without notice. Information provided by CUI is believed to be accurate and reliable. However, no responsibility is assumed by CUI for its use, nor for any infringements of patents or other rights of third parties which may result from its use. CUI products are not authorized or warranted for use as critical components in equipment that requires an extremely high level of reliability. A critical component is any component of a
Updated at April 27, 2026
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