Adrian Stott formulated on Saturday : > On Sat, 21 Aug 2010 09:41:41 +0100, Eno at Yahoo > <[email protected]> wrote: > >> Hi, >> >> Has anyone any idea how long in general terms it will take a normal >> sized alternator (50 amp) to recharge two 110amp batteries, and >> recharge the starter battery back to its pre starting level assuming it >> was fully charged before starting the engine. >> >> I know there are a number of variables that would need to be known to >> give an accurate answer, but just for general everyday type use and >> using normal levels of power, example:- TV for 2 hours, 2/3 (20w) lights >> for 5 hours and the water pump and 12 volt compressor fridge. >> >> As a general guide how long would you think the engine would need to run >> to replace the energy lost. >> >> Thanks > > There is a significant problem with your question, if it assumes > running the main engine while the vessel is at rest. That's because > this is a very inefficient use of the engine. Recharging is much > better (and more sustainably) done using a for-the-purpose generator > with an engine sized for the job and running at an efficient load > level. > > Also, it is very worthwhile to have a smart charger. This can be in > the form of a smart alternator controller, but many systems use a > multi-level dedicated charger (which raises the voltage, etc., as the > battery nears full charge). This significantly reduces the needed > recharging time. It also lengthens battery life, by achieving a full > charge (which conventional alternators usually don't achieve). > > During the several years I had no mains at my mooring, I ran my > generator every day to replace the energy I used for domestic purposes > (fridge, electronics, lighting, pumps, the works). I have a good > charger (50 A, 24 V) and a 500 Ah 24 V battery. I found the battery > could reach float level after about 2.5 hours of charging( per day). > > Does that help? I doubt it as he wants to know how long to run the engine so I think its a good bet he doesn't own a generator and smart charger at hand.
-- Brian traveling on Harnser http://nbharnser.blogspot.com/ ------------------------------------ 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: [email protected] [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/
