UL60950 ITE Power Supply Evaluation 20030917.pptVIP

UL60950 Information Technology Equipment Power Supply Evaluation Presented By: Alien Wang UL 60950 – 3rd Power Supply - Information Technology Equipment QQGQ/7 e.g. Linear Power Adaptor, Switching Power Adaptor. QQGQ2/8 e.g. ATX Switching Power Supply, DC/DC Power Supply, Open Frame Power Supply. Redundant Power Supply. Classification Class I : Power Supply with Protective Earth Protection. Class II : Power Supply with Double (Reinforced) Insulation. Note: DC/DC Power Supply ? Depends on end product use and supply source. Mobility of Equipment Movable Equipment: -18 kg or less in mass and not fixed, -equipment with wheels, castors or other means. Transportable Equipment: -Moveable Equipment that intended to be routinely carried. Direct Plug-In Equipment: -Intended to be used without a power supply cord; the means plug forms an integral part of the equipment enclosure. Note: Normally Mobility apply only on QQGQ/7. Circuits Characteristics AC Mains Supply: External a.c. power distribution system supplying power to the equipment. Primary Circuit: Directly connected to AC Mains Supply. Secondary Circuit: Not Directly connected to AC Mains Supply. Circuits Characteristics Hazardous Voltage: Voltage exceed 42.4 V peak, or 60 V dc and not meet Limited Current Circuit or TNV Circuit. ELV Circuit: Voltage not exceed 42.4 V peak, or 60 V dc under normal condition. SELV Circuit: Voltage not exceed 42.4 V peak, or 60 V dc under both normal condition and single fault condition. Principles of Safety Prevent From Hazard Electric Shock Energy Related Hazards Fire Heat Related Hazards Mechanical Hazards *Radiation Hazards *Chemical Hazards Electric Shock What is Hazardous Voltage? Voltage exceeding 42.4 V peak, or 60 V dc. Not meet the requirements for either a Limited Current Circuit or a TNV circuit. Electric Shock Hazardous may result from- Contact with bare parts at H.V. Breakdown of insulation between parts of H.V. and accessible conductive parts. Break