I think the crux of this strand of the thread is that "it depends". Rules are made to try and make things safer, but no rule can cover all situations. As Arild points out, sometimes it is best to leave the device shut down as in a conveyer belt, sometimes it is best to leave them to come back on, as in the lights.
One of the things I love about engineering my boat is that I am free to make it the best I can make it and not be held back by some insurance oddsmaker writing blanket rules for the lowest common denominator. Norm S/V Bandersnatch Lying Julington Creek 30 07.695N 081 38.484W > [Original Message] > From: Arild Jensen <[EMAIL PROTECTED]> > To: <liveaboard@liveaboardnow.org> > Date: 7/24/2008 8:49:22 PM > Subject: [Liveaboard] Latching relays ( was: 12 VDC buss ) > > > > Lew Hodgett wrote: > > > > >From a safety stand point, latching relays are a disaster waiting to > > happen. >>>>>>>>>>>>>SNIP <<<<<<<<<<<<<<< > > > > Why exclude latching relays? SAFETY. > > > > If you loose power, the only safe way is to reset every thing to the off > > position and start over. > > > > A relay with a basic holding circuit accomplishes this by providing > > under voltage protection. > REPLY > Why indeed? Lew you bring up an very contemporary topic. Also a > hotly debated issue. <VBG> > > It used to be devices were designed to FAIL SAFE. Especially in motor > controls etc. > Thomas Kobelt of Kobelt Engineering gave a presentation to the > Vancouver chapter of Marine Engineers. > He mentioned that IMO had begun a shift to a new and very different > concept. called FAIL in MODE. > It was obvious from the audience reaction they had widely divergent > opinions on the subject. _______________________________________________ Liveaboard mailing list Liveaboard@liveaboardnow.org To adjust your membership settings over the web http://www.liveaboardnow.org/mailman/listinfo/liveaboard To subscribe send an email to [EMAIL PROTECTED] To unsubscribe send an email to [EMAIL PROTECTED] The archives are at http://www.liveaboardnow.org/pipermail/liveaboard/ To search the archives http://www.mail-archive.com/liveaboard@liveaboardnow.org The Mailman Users Guide can be found here http://www.gnu.org/software/mailman/mailman-member/index.html
