Battery Maintainer / Charger Problem

(Shooter) · (Shooter) **Join Date: Apr 2010** 05-23-2010, 3:06 PM

Boat: 2003 SAN 210
Batteries: 2 Optima blue top
Onboard charger: Dual Pro RS1
Battery Switch: 2 BEP battery switches (one for each battery)

This winter I decided to add an onboard battery maintainer. I have had no problems with my batteries until now. I have two batteries (one in the rear and one in the bow). I installed a single bank maintainer on the rear battery. I plugged it in and left both battery switches on to allow the maintainer to work its magic on both batteries. I jumped in the boat today and it appears both of my batteries are now dead.

The maintainer appears to be working. The green power light and green status lights are on, but the red charging light is off. If I restart the maintainer, it will indicate a charge for about ten seconds and go to standby. It appears the maintainer thinks the batteries are charged. Do I have a bad maintainer or am I doing something wrong?

(ottog1979) · (ottog1979) **Join Date: Apr 2007** 05-23-2010, 3:40 PM

I'm not good at electronics and having just replaced both batteries, am dealing with this same issue now. I'm betting the cause is the same as outlined in Tuneman's post in this thread:

http://www.wakeworld.com/forum/showthread.php?t=778522

(srock) · (srock) **Join Date: Mar 2002** 05-24-2010, 11:18 AM

You need two chargers or a 2 bank charger for your situation. You do not want both batteries connected together because they will discharge into the weaker battery. I found Deltran chargers website (batterytender.com) to have a lot of useful information. I'm not sure about your chargers specs but you want a "smart" charger that drops off when your battery is full.

If you use the charger shown, you need to charge one battery at a time.

(murphy_smith) · (murphy_smith) **Join Date: Dec 2005** 05-24-2010, 11:20 AM

Stick with the Dual Pro...it is much better technology that the battery tender. Not to say that Battery Tender is bad, but I wouldn't go spending money to replace the Dual Pro.

(srock) · (srock) **Join Date: Mar 2002** 05-24-2010, 11:26 AM

Just looked at the dual pro, its not the charger but the way its being used.

(Shooter) · (Shooter) **Join Date: Apr 2010** 05-24-2010, 4:20 PM

I originally had a 2 bank charger, but was told a single bank would do the job and returned it. I may still have it installed improperly, but if it will discharge into the "weaker battery", doesn’t that mean I should have at least one good battery?

(talltigeguy) · (talltigeguy) **Join Date: Sep 2003** 05-24-2010, 5:40 PM

Shooter,

Is there a switch on the charger to differentiate between the type of battery used? Optimas don't like to be charged the same way that lead acid batteries are charged....it may kill them over the winter for sure. You left it plugged in all winter?

What does the voltage read on your batteries when the charger is not connected?

(Shooter) · (Shooter) **Join Date: Apr 2010** 05-24-2010, 8:56 PM

No switch, it looks like its just plug and play. I left it plugged in for over a month. I thought maintainers are to be left plugged. I had 10V, but have used a normal battery charger over night and it looks like the batteries are now charged and working fine.

What charger is recommended for Optimas?

(justintime) · (justintime) **Join Date: Mar 2009** 05-25-2010, 5:15 PM

you never charge with the battery switches on

yes the dead battery will discharge the other one

best is to buy a 2 way switch and not signal switches