Very useful, and well worth knowing. Mind you, as an owner of an old lump with technology out of the ark, I'll stick to what should perhaps be called the Ardvark.
Steve Sent using BlackBerry® from Orange -----Original Message----- From: Bruce Napier <[email protected]> Date: Thu, 9 Apr 2009 09:02:03 To: <[email protected]> Subject: Re: [canals-list] Re: Washing machines afloat On 9 Apr 2009, at 07:37, [email protected] wrote: > Why won't Bruce buy an Adverc then? Come on Bruce, spell it out... > well, give us the headlines at least. I'm still at that naïve state > of believing that its just a battery management system which keeps > up my vo Chris Gibson's page gives chapter and verse, but in summary, AIUI, battery management systems came into being because the original automotive derived alternators only ran at 13.8 V (to avoid boiling starter batteries), and were machine sensed rather than battery sensed, which meant that if you were using a splitting diode to charge both domestic and starter batts, the voltage drop over the diode meant that the alternator shut down prematurely. Now we have twin alternator set ups, so we don't need a splitting diode, and machine sensing and battery sensing should see the same voltage, unless you've got an alarming drop over the cable between the alt and the batt. Modern alternators run at 14.4 V, and have much higher outputs of course. (Because automotive requirements are now very similar to ours: think of the kit a modern HGV cab has on board, and the consequent domestic demand.) So most BMS's achieve nothing. The only remaining advantage of the Adverc is the alternating higher and lower charge voltage regime, and there's not a lot of evidence that this actually achieves much. So, if you have an older system, with one, low output, alternator and a splitting diode, you'll get benefit from a BMS; ideally (according to Chris!) the Smartbank system that uses the Smartgauge to control the charge to the two banks. If like us you have a modern Jap based engine with a socking great dedicated domestic alternator (the latest versions do 170A) then a BMS is a waste of money. If I've got any of this wrong, I'm sure one, some or all of Messrs Millin, Edwards and Brooks will be along soonish to put me right! Meantime, HTH –– All the best Bruce "The superior man knows what is right, the inferior man knows what will sell" Analects of Confucius, circa 500 BCE [Non-text portions of this message have been removed] ------------------------------------ Yahoo! Groups Links ------------------------------------ Yahoo! Groups Links <*> To visit your group on the web, go to: http://groups.yahoo.com/group/canals-list/ <*> Your email settings: Individual Email | Traditional <*> To change settings online go to: http://groups.yahoo.com/group/canals-list/join (Yahoo! ID required) <*> To change settings via email: mailto:[email protected] mailto:[email protected] <*> To unsubscribe from this group, send an email to: [email protected] <*> Your use of Yahoo! Groups is subject to: http://docs.yahoo.com/info/terms/
