... 3.High efficiency DC TO DC Vehicle Power Supply 30W Safety Approvals UL/CUL, PSE, GS, BS, CE, CB, FCC, and EK-Mark Protections1)over voltage ... % Environmental requirement1)operating temperature: 0-402)storage temperature: -20-853)opera ting relative humidity:595%RH4) Withstanding voltage: AC 3,000V (minimum ...