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Bus Discussion => Bus Topics ( click here for quick start! ) => Topic started by: Jim Eh. on September 28, 2016, 09:34:59 AM

Title: Battery Maintainer
Post by: Jim Eh. on September 28, 2016, 09:34:59 AM
Seems to be quite a bit of talk about batteries lately. Since my batteries were always going flat while sitting (ECM draw?) I installed a smart charger. 3A @ 24V with auto monitoring. I have not checked about any issues I may come across with my equalizer. Is this something I should be concerned about. BTW, it took almost 4 days to bring the batteries up to full charge when I installed it. There have been some that I talked to that say a battery maintainer is a bad idea as the battery life depends on a limited number of charge cycles. They say constantly charging the batteries will shorten their life. Floor is now open.
Title: Starter Battery Expected Life? ...
Post by: HB of CJ on September 28, 2016, 09:55:06 AM
Three, (3) amps charging a 24 volt system of starter batteries might take quite some time if they were deeply discharged.  I for one do not think a maintainer would greatly decrease your starter battery life.  Lots of phantom or known rate discharge goodies with your application.  A three, (3) amp discharge rate is huge.  Gaging the exact discharge rate might help determining a maintenance charging rate.  If needed, do not forget the water.

Or just park on a hill?  Or bump start using the toad?  Or draft a bunch of folks and just push?  :)
Title: Re: Battery Maintainer
Post by: Iceni John on September 28, 2016, 10:44:28 AM
3 amps at 24 volts is 72 watts  -  that's way more than an ECM needs when not running.   I measured my DDEC II ECM power draw:  it takes about 8 mA on standby.   That's still enough to slowly draw down a Group 31 after several weeks, but an hour or less of charging is then sufficient to bring it back to 100%.

My guess is that you have other phantom loads.   Maybe a 100 watt solar panel and a simple PWM charge controller would be good for keeping everything charged?   Remember, battery maintainers do just that  -  they are not chargers per se, but they prevent batteries from self-depleting without any loads.

John
Title: Re: Battery Maintainer
Post by: luvrbus on September 28, 2016, 10:53:34 AM
Battery life is affected by cycles discharge and recharge the maintainers takes the cycle away by not letting the battery discharge so it extends the life of a battery   
Title: Re: Battery Maintainer
Post by: Dreadnought on September 28, 2016, 11:29:10 AM
I got a new set of very expensive 8D batteries in 2012. I learned a lesson about keeping them topped up and the bus elec system disconnected when not in use. I've since used Battery tenders for all my batteries and the 8Ds are in top condition!

Title: Re: Battery Maintainer
Post by: Jim Eh. on October 03, 2016, 03:40:42 PM
Quote from: luvrbus on September 28, 2016, 10:53:34 AM
Battery life is affected by cycles discharge and recharge the maintainers takes the cycle away by not letting the battery discharge so it extends the life of a battery   

Never looked at it that way. Great. I would use a solar charger but I park indoors so a maintainer is my only option. Sometimes it would take a week to run the batteries down to the point of a no start, sometimes a little less. I believe it is rated from 3 amps max to zero amps when batteries are fully charged. I was told that if the batteries are discharge below the 3 amp requirement it simply will not work. A lesson I learned with my floor scrubber (bad set of batteries) after I bought this maintainer. I thought my scrubber charger was toast but it was just the battery bank. After the new batteries were installed the charger started working.

Thanks for the input.
Title: Re: Battery Maintainer
Post by: chessie4905 on October 03, 2016, 06:12:18 PM
Check out pulse chargers
Title: Re: Battery Maintainer
Post by: TomC on October 04, 2016, 04:40:54 AM
I keep my Kenworth's 4-31 starting batteries up with a solar charging panel. My bus is plugged in.
Title: Re: Battery Maintainer
Post by: belfert on October 15, 2016, 10:24:19 AM
I have killed several sets of starting batteries by not having a smart charger on them.  The current set are going on six years with a Battery Tender on them when not on the road.
Title: Re: Battery Maintainer
Post by: daddysgirl on October 16, 2016, 11:30:59 AM
Your bus is different than mine, but check for "spare" studs with connections that have been made to them. On my bus, stud 55 in the front will drain the left bank if I don't keep my battery minder plugged in while at home. Just a thought.