For standard lead-acid batteryies ~10.5v is pretty much the definition of 0% charge and can seriously diminish the number of cycles remaining in the battery's life span. That is if you can get it to accept a charge at all. ~11.6v is about 50% and 12.7v is full charge 100%. The deeper you discharge a battery the fewer cycles it has in it's life span. Often times deep cycle batteries are rated for 200 cycles down to 50% and back up. Less deep of a discharge = more cycles. So you may have taken a few cycles off but they will likely remain functional for many more years.
Josh Muckley S/V Sea Hawk 1989 C&C 37+ Solomons, MD On Jun 22, 2016 8:22 AM, "Danny Haughey via CnC-List" <cnc-list@cnc-list.com> wrote: The batteries were new last July. I charged them with my home charger separately a few weeks ago with no issue. I had forgotten to turn the battery switches off and they dropped to about 11v. So, this time, I decided to get an adapter and use the shore power outlet to run the on board charger. It's the first time I've tried it. I am trying to top up 3 group 27s. I believe the batteries are fine. DannyOn Jun 22, 2016 12:42 AM, Russ & Melody via CnC-List < cnc-list@cnc-list.com> wrote: > > Hi Pete, > > If the batteries are shot, don't they get warm with hard charging? Danny's original message says the batteries are not warm. > > Maybe he is deep cycling the battery bank. > > Cheers, Russ > > > > At 09:27 PM 21/06/2016, you wrote: >> >> Content-Type: multipart/alternative; >> boundary="----=_NextPart_000_01F9_01D1CC14.71395510" >> Content-Language: en-us >> >> Dan – >> This may be an indication that your batteries are shot. The charger is working to give them a juice and they’re just not having it. Take a look at them before you change your charger. But also look for loose connections. >> >> >> >> >> From: CnC-List [ mailto:cnc-list-boun...@cnc-list.com] On Behalf Of Russ & Melody via CnC-List >> Sent: Tuesday, June 21, 2016 11:10 PM >> To: cnc-list@cnc-list.com >> Cc: Russ & Melody >> Subject: Re: Stus-List Battery charger getting warm >> >> >> Hi Danny, >> >> I like how you find it goes grey, most of your fellows call it gray. :) >> >> Anyhow, the meter pegs over 30 amps, let's say 35 for this discussion... and at 15 volts we're looking at something near 500 watts to the batteries. If it's a 90 percent efficient battery charger then it has to dump 50 watts or so into the surroundings. >> >> For perspective and giggles, turn on a 40 watt light bulb and see how long you can hang on to it. Yow! >> >> A machine at 160 F, you can touch but not hold your hand on for very long, 180 F is tolerable for less than a second. From your description, I suggest the battery charger is operating around 150 F if you can put pressure on it with your hand. That is not a worry if it's like that for a few hours. I am also assuming ambient cooling (no fan). >> >> Cheers, Russ >> Sweet 35 mk-1 >> >> >> At 05:20 PM 21/06/2016, you wrote: >> >> Hi guys, >> When I turn the battery charger on it greys very warm. The Guage pins all the way past 30 amps. >> >> It is not too hot to touch but too hour to hold your hands on for very long. The batteries are not warm and seem to have taken some charge over a couple hours. >> >> It's this normal? I don't like that heat... >> _______________________________________________ >> >> This list is supported by the generous donations of our members. If you like what we do, please help us pay for our costs by donating. All Contributions are greatly appreciated! _______________________________________________ This list is supported by the generous donations of our members. If you like what we do, please help us pay for our costs by donating. All Contributions are greatly appreciated!
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