Hello Andreas:
1) PCMCIA cards. a. I have not heard of any safety problems IN PCMCIA cards. It is possible that a fault in the card could cause an overheating event in the card. For an overheating event to develop into a fire, the combination of the card and the host computer would have to provide air (oxygen) to the fuel for any fire to exist. Within the PCMCIA card assembly, there is insufficent air to allow a fire to develop. Even before a fire erupts, the heating usually causes oxidation which will consume any available oxygen in a small space. Therefore, the heating event would have to be sufficiently great as to cause heating of fuel materials in the host computer to ignition temperatures. Ignition temperatures of plastics range from 350 C to 475 C. It is unlikely that a fault in the PCMCIA card can dissipate sufficient power to heat a plastic in the host computer to ignition temperature before the failure becomes so gross as to open a component and interrupt the current. You asked about safety problems CAUSED BY the PCMCIA card. A safety problem caused by the card would likely appear in the computer. Typically, this would be an overheating situation somewhere in the computer circuits that provide power to the PCMCIA card. b. Warnings against other brand PCMCIA cards. This may be a good idea from a safety point of view, but severely limits the usefulness of the PCMCIA capability. The only hazard associated with PCMCIA cards is that of fire. I've already mentioned that it is unlikely that a PCMCIA card could itself burn. The host computer slot can be constructed so as to prevent spread of heating such as by using a metal enclosure around the PCMCIA slot so as to act as a heat sink in the event of an overheating event. Further protection against overheating can be provided by controlling the overcurrent to the PCMCIA card by means of a fuse or a current-limiting regulator. c. PCMCIA card manufacturers safety tests? I don't know. But, I would doubt it. The amount of testing is immense base on all the different notebook and other PCMCIA card applications. d. Safety tests with PCMCIA cards in place? Yes and no. Input tests would be done with all PCMCIA slots loaded to maximum power. Same for the heating tests. IEC 950 says that no abnormal fire tests are necessary if the supply is "Limited Power" (as specified in Sub- clause 2.11). Most notebook computers are powered from a "Limited Power" source, hence no abnormal testing. (The battery is NOT a "Limited Power" source, but if it is provided with a fuse, then it is a "Limited Power" source.") 2) IEC 950 for notebook computers or ac adapter or both? The Scope of IEC 950 states, "This standard is applicable to mains-powered or battery-powered information technology equipment..." The Scope would therefore include BOTH the computer and the ac adapter. However, in some countries (e.g., USA), low voltage equipment is exempt from third-party safety certification. Best regards, Rich ------------------------------------------------------------- Richard Nute Quality Department Hewlett-Packard Company Product Regulations Group San Diego Division (SDD) Tel : 619 655 3329 16399 West Bernardo Drive FAX : 619 655 4979 San Diego, California 92127 e-mail: ri...@sdd.hp.com -------------------------------------------------------------