Like most regulatory issues the answer is YES and NO. Therefore it is dangerous and extremely misleading (to many lurkers) to apply a general answer to all conditions: * Generally the equipment is expected to protect itself with internal over current and short-circuit protection. * The equipment will be tested with the worst case fault condition – 60 kAmp or more is not uncommon * If the equipment is simple and cannot be protect itself (e.g. a table lamp) then we rely upon the domestic breaker (hoping that the electrician follow CODE and not his own initiative) that is why the cord will have minimum x-sectional area and maximum length. (Expect where UK style plugs are used - these carry an internal fuse from 1 Amp to 13 Amps). It is also why CODE violations are prosecuted – we must guarantee that the correct type of breaker is fitted in each domestic circuit. * Where we rely upon the ‘breaker’ for - non-domestic equipment - it is ALWAYS mandatory (and common sense) to specify the characteristics of that breaker in terms of ‘tripping (operating) current’ – time characteristics (Type I, II or III) and Breaking Current 2,500 Amps is low for most domestic situations. A failure to provide the necessary information WILL eventually result in a fire or nuisance tripping. You should fine that all test labs will have the same interpretation – I suspect that submissions PASSED are correct – whilst those that were REJECTED were not correct. Best regards Gregg
From: [email protected] [mailto:[email protected]]On Behalf Of peter merguerian Sent: Tuesday, January 28, 2003 2:54 PM To: [email protected] Subject: Circuit Breaker Tripping Dring Fault Tests Dear All, For safety, it is not clear from the standards whether the main branch circuit breaker tripping during fault conditions is an acceptable result. I see no reason why this should not be acceptable. What is your view? Some third party labs find it acceptable and others do not. Anyone can lead me to some inernational decisions regarding this issue? Thanks, Peter _____ Do you Yahoo!? Yahoo! <http://rd.yahoo.com/mail/mailsig/*http://mailplus.yahoo.com> Mail Plus - Powerful. Affordable. Sign up now <http://rd.yahoo.com/mail/mailsig/*http://mailplus.yahoo.com>
