How to Choose a Mean Well 400W Semi-Potted Weatherproof Power Supply for Outdoor Lighting

• Author：David
• Release time：2025-11-21
• Click：83

1. Method 1: Certifications and Protection are the Cornerstone
Core: Identify authoritative certifications and an IP54 protection rating.
When selecting, first confirm the product has safety certifications like CE and UL, and possesses an IP54 rating. This ensures the power supply is protected against dust ingress and water splashes, allowing it to withstand outdoor rain and humid environments, forming the foundation for long-term stability.

2. Method 2: Scientifically Calculate Load and Margin
Core: Reserve a power margin of 1.5 times the actual load.
If the total power of the LED fixtures is 250W, choosing a 400W power supply (250W * 1.5 = 375W < 400W) is ideal. This margin prevents the power supply from operating at full load, significantly extends its lifespan, and allows room for future expansion by adding more lights.

3. Method 3: Consider Installation Environment and Heat Dissipation
Core: Ensure the installation location is well-ventilated, avoiding enclosed spaces.
Although the semi-potted process provides moisture resistance, good heat dissipation is still crucial. Install it in a well-ventilated area and never seal it inside a enclosed box. The metal casing of the Mean Well power supply is a key component for heat dissipation; proper cooling ensures efficient and continuous output even during high summer temperatures.

4. Method 4: Compare Craftsmanship and Long-Term Cost
Core: Understand the balanced advantages of semi-potted technology in heat dissipation and protection.
Compared to simple potting or full potting, Mean Well's semi-potted design only seals the core components, balancing moisture resistance, shockproofing, and heat dissipation needs. Although the unit price might be slightly higher, its extremely low failure rate and long lifespan significantly reduce maintenance costs, achieving better long-term value.

MEAN WELL

400W Single Output Switching Power Supply

ERPF-400 series

User's Manual

131352Part1)IEC6090-48R-41070483fort2,2%onty

■Features

·Universal AC input/Full range

(Withstand 300VAC surge input for 5 seconds)

·Built-in active PFC function

·High efficiency up to 91%

·Design against rain splash

·Protections:Short circuit/Overload/Over voltage/

Over temperature

·Cooling by free air convection

·LED indicator for power on

·Low cost,high reliability

·100%fullload burn-in test

3 years warranty

RCc  usER[CBC∈

■Applications

·LED strip lighting

·LED channel letters

·LED display

■GTIN CODE

MW Seach:htts:/ww.meanwellcom/serviceGTIN.aspx

Description

ERPF-400 series is a 400W single output enclosed type AC/DC power supply with the active PFC design

.It adopts an aluminum case and the interior is semi-potted,protecting the internal electronic componentsfrom rain splash and dust.With the complete protection functions,ERPF-400 is suitable for the applicationssuch as outdoor LED channel letters,billboard,commercial display,etc.

■Model Encoding

ERPF-400-24Output voltage(12V/24V/48V)Output wattageSeries name

FNe Name:ERPF-400-SPEC 

MVMEAN WELL

400W Single Output Switching Power Supply

ERPF-400 series

SPECIFICATION

MODELERPF-400-12ERPF-400-24ERPF-400-48DC VOLTAGE12V24V48VRATED CURRENT30A16.7A8.3ACURRENT RANGE Note.50~30A0~16.7A0~8.3ARATED POWER360W400.8W398.4WRIPPLE&NOISE(max.)Note.2150mVp-p150mVp-p240mVp-pOUTPUTVOLTAGE ADJ.RANGE10.8~13.2V21.6～26.4V43.2~52.8VVOLTAGE TOLERANCE Note.3±1.0%±1.0%±1.0%LINE REGULATION±0.5%±0.5%±0.5%LOAD REGULATION±0.5%±0.5%±0.5%SETUP,RISE TIME2000ms,100ms/230VAC;3000ms,100ms/115VAC at ful loadHOLDUPTIME(Typ.)10ms/230VAC;10ms/115VAC atful loadVOLTAGE RANGE Note.490~264VAC127~370VDCFREQUENCY RANGE47～63HzPOWERFACTOR(Typ.)PF≥0.95/230VAC,PF≥0.98/115VACINPUTEFFICIENCY (Typ.)89%90%91%AC CURRENT (Typ.)2.5A/230VAC 3A/115VACINRUSH CURRENT (Typ.)cold start 45A/115VAC,90A/230VACLEAKAGE CURRENT<1mA/240VACOVERLOAD105~135%rated output powerProtection type:Constant current imiting,recovers automatically after fault ondition is removedSHORT CIRCUITProtection type:Constant current imiting,recovers automaticaly after fault condition is removed13.8~16.2V27.6~32.4V55.2~64.8VPROTECTIONOVER VOLTAGEProtection type :Shut down O/P voltage,re-power on to reooverOVER TEMPERATUREShut down O/P voltage,recovers automaticallyafter temperature goes downWORKING TEMP-30~+60℃(Refer to output boad derating curve)WORKING HUMIDITY20~90%RH non-condensingEMVRONMENTSTORAGE TEMP.,HUMIDITY-30~+85℃,10~95%RHTEMP.COEFFICIENT±0.1%/℃(0~35℃)VIBRATION10~500Hz,3G 10min./1cydle,60min.each alongX,Y,Z axesSAFETY STANDARDSUL60950-1,IEC/BSEN/EN62368-1,GB4943.1,EACTPTC004,IS13252(Part1)(for 12,24 only)approvedSAFETY&WITHSTAND VOLTAGEI/P-O/P:3KVAC V/P-FG:2KVAC O/P-FG:0.5KVACEMCISOLATION RESISTANCEVP-O/P,IVP-FG,O/P-FG:100M Ohms/500VDC/25C/70%RH(Note.6)EMC EMISSIONCompliance to BS ENEN55032(CISPR32)classA,GB17625.1,GB/T 9254.1;BS ENEN61000-3-2;BSEN/EN61000-3-3,EAC TPTC020EMCIMMUNITYCompliance to BS EN/EN61000-4-2,3,4,5,6,8,11,BSENEN55035;light industry level,EACTP TC020MTBF1981.2Khrs min.Teloordia SR-332(Bellcore)233.4Khrs min.MIL-HDBK-217F(25℃)OTHERSDIMENSION220.4*130*48mm (L*W^H)PACKING1.1Kg;9pcs/11Kg/0.63CUFTNOTE1.All parameters NOT specally mentioned are measured at 230VAC input,rated load and 25℃ of ambient temperature.2.Ripple &noise are me asured at 20MHz of bandwidth by using a 12"tiwisted pair-wire terminated with a 0.1uf&47uf parallel capacitor.3.Tolerance:indudes set up tolerance,line regulation and load regulation.4.Derating may beneeded unde low input voltages.Pleasecheck the static characteristics for more details.5.Please refer to "Static Characteristics".6.The power suppl is considered a component which wl be instaled into afinalequipment.Althe EMC tests are been executed by mounting the unit ona 450mm*450mm metal patewith 1mm of thickness.The final equipment mustbe re-confimed thatit stilmets EMC directives.For guidance on how toperform these EMC tests,please refer to "EMI testingofcomponent power supplies."(as avalilable on https:/ww.meanwell.com//Upload/PDF/EMI_statement_en.pdf)※ Product Lability Disdaimer :For detailed information,pleaserefer to https:/ww.meanwell.com/serviceDisclaimer.aspx

File Name:ERPF-400-SPEC