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03-14-2013 03:54 PM
Re: Did I kill my battery?

Originally Posted by rhr1956 View Post
Honey, did you turn the lights off? My reply was yes. The problem I discovered two days later was, no I had not turned the lights off. The battery was dead as hell. It did show 5.4 volts. I have it on the smart charger now. Do you think I kiilled it or will it recover? It is an AGM battery.
If it accepts the charge and gets back to about 12.8 volts after charging and the float voltage has dissipated put it back into service.

However will almost certainly have lost a little of it's capacity and will die a little sooner.
03-14-2013 10:07 AM
Re: Did I kill my battery?

I can say that when HD went to AGM batteries on their bikes a complete discharge destroyed the batteries(yes...plural...don't ask). Charge it fully and watch the performance for a while to be safe.
03-14-2013 09:09 AM
Re: Did I kill my battery?

letting a battery drain or even a couple of times will not kill it.. on a regular lead acid battery, it will cause sulferacation.. not so sure on an AGM.

But think about it.. how many times have people completely drained car batteries with little to no issues other than needing a jump to get the car started right afterwards?
03-14-2013 08:31 AM
Re: Did I kill my battery?

The LVD above is okay for a low amp single circuit.
For a starter circuit, or the entire boat you can expect to spend more.
Here's a link to a series of LVD's that will protect starter circuits/batteries and the entire boat (200amp for example).
Battery-Related Products | Low Voltage Disconnect Switches48510 | Cole Hersee - Littelfuse

The cost a bit more than a tenner. They protect more than a single switch on the panel being forgotten.

The advantage is you'll never wake up in the morning and not have the juice to crank the engine, or drive 2 hours to your boat for a beautiful day of sailing and then spend two hours charging a dead lump of plastic lead and acid.

Here's one with a price listed - 130 amp capable, 263 bucks
03-14-2013 02:26 AM
Re: Did I kill my battery?

You should take more care your battery, nor you will kill your battery.
03-14-2013 02:24 AM
Re: Did I kill my battery?

Maintenance is very simple, to reduce the depth of discharge.
03-13-2013 11:15 PM
Re: Did I kill my battery?

Nice looking piece of kit and only a tenner! Sign me up.
03-13-2013 05:24 PM
Re: Did I kill my battery?

Originally Posted by rhr1956 View Post
Where is a good source to get a low voltage cutoff switch? How does it get wired in?
I've recently got one of these to install before my boat vent :

Got it for a tenner (sterling, that is) on Fleebay. They are sold under the name "Brocott" or "Kemo" battery guard or Kemo M148A.

You can adjust the cut off voltage on the small yellow potentiometer knob. Installation is easy - Wire it between your battery (and fuse) and your load (max 20Amp if you install it on a heatsink).
03-13-2013 04:32 PM
Re: Did I kill my battery?

Where is a good source to get a low voltage cutoff switch? How does it get wired in?
03-13-2013 04:00 PM
Re: Did I kill my battery?

well, yeah, dead.
You should have a low voltage cut off at 10.2 to save the beast.

You may be able to recharge it, if so make sure you get a good, FULL charge on.
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