Battery and charging

[dgetswet]

Sorry for the long story wanted to lay it iut.

Okay I was told I don't have a problem but my voltage light is always on. I have a 2004-05 Albin 28TE. I have a Perkins Sabre 300Ti. When I purchased the boat it had a 12 volt battery for starting and bow thruster and 4 6 volt batteries in series and parallel for the house. I had issues with all the batteries.
I replaced the batteries with 1 12 volt AGM for the start and thruster ans 1 4D AGM battery for the house.
I had the alternator rebuilt which was not working correctly.
The re-builder told me this was a French company alternator and only puts out 14 volts when charging not the 14.7 American alternators put out. I asked him why the little (idiot) light stays on when I switch to the house battery or when on both. He said there is no problem.

Now My on board battery charger does not charge my batteries fully. I cannot find the setting to change for AGM batteries but was told by a professional I did not need to change the setting it will just charge slower.

Has anyone else had any of these issues? I really don't want to mess up almost a $1000 worth of batteries and an alternator. When I switched over from the 6 volt batteries did I need to make any other adjustments? They were in series as 2 -12 volt batteries.

Once again thanks for any words of wisdom.

[Yearwood]

Four 6 volt batteries in series results in 24 volts. Ahha see the corrections at the end.

[Pitou]

When using 6 - Volt batteries for a house bank, the correct way to connect them to provide 12-volts and is "in series and in parallel. This doubles the voltage and the capacity. For my House Bank, I have six - 6 Volt golf cart batteries wired this way giving me 12 Volts and ~ 750 AH .. if I had four of these 6 volt batteries wired this way it would still be12 Volts, but at 500 AH.

House Bank.jpg

[dgetswet]

Four 6 volt batteries in series results in 24 volts. Ahha see the corrections at the end.

It was set up to run as 2 12 volt batteries. That was checked when it was purchased.

[dgetswet]

Yes that was the way they were set up. Forgot to say in parallel.

Which leads me to my problem. I am still not charging. I pulled all the cables off the 4D 12 volt and put a portable charger on 3 amp slow charge to make sure the battery does take a charge. For all I know the battery had an issue.

When using 6 - Volt batteries for a house bank, the correct way to connect them to provide 12-volts and is "in series and in parallel. This doubles the voltage and the capacity. For my House Bank, I have six - 6 Volt golf cart batteries wired this way giving me 12 Volts and ~ 750 AH .. if I had four of these 6 volt batteries wired this way it would still be12 Volts, but at 500 AH.

House Bank.jpg

[nebulatech]

Hey Don, that's pretty frustrating! What kind of voltage are you getting after charging for a while? What is the voltage coming off your charger while charging?

Most electrical issues are due to bad connections. It's probably worth inspecting all the fittings.

To find out if the battery is defective, you might find it helpful to check the conductance/internal resistance. Here is an amusing video showing an affordable harbor freight meter for this test:
https://m.youtube.com/watch?v=XtWflJTp_mM

You would need to call the battery manufacturer and ask an engineer the actual spec. original internal resistance and hopefully get some idea of what internal resistance would indicate a bad battery. They don't like to say because temperature will affect the reading, and so will a recent charge or load, but it's all relative. If your original internal resistance is supposed to be 3 ohms, then if you get a reading of twice that, its bad news. (I'm no expert here, so take my thoughts with a grain of salt)

[dkirsop]

I know the shop says your alternator is ok but try this simple test. With the ignition on and the engine not running put a screw driver near the alternator pulley. You should have a strong magnetic pull at the pulley. Second test, with the engine running check the voltage at the alternator output if it is low then you have either a blown diode or a bad regulator. The fact that your red light stays on indicates a low voltage output from your alternator and this to me is where your problem will be.

[JBrooks]

If you have a Xantrex Truecharge 2 40 as your charger, I can help you with an easy upgrade for a remote control pad from Xantrex. My battery charger is very hard to reach let alone read the thing. I added a remote panel in the front cabin to control it. One RJ45 cable connects the two.

On another note, I can give you pointers if you ever change your impeller. I have a Perkins M265TI on my 30FC and only access to it is from the port quarter berth.

[johngus]

to check the alternator with the engine running put volt meter on battery or at the positive post at the alternator.you should see approx 14 volts.some at idle with loads may be less but at 1500-2000 rpm should see at least 14 volts.if its putting out 14v could be an issue with the light circuit

[dgetswet]

So just to follow up the battery and charging system back on track. Got rid of all the 6 volt batteries. Replaced all new 12 volt AGM and a 12 volt 4D AGM. Rebuilt the alternator and was great for a couple days. Had the mechanic take a look at it and found the charging system was not working so the alternator was overworking. He adjusted the charger and fix the wires by the main charger fuse. Bottom line all systems go. Funny how an expensive marine electrician could not find this last year and a diesel mechanic took 5 minutes to fix.

[nebulatech]

Thanks for following back up. So glad you got it fixed!

Sounds like wiring was part of the culprit, and the improper charge may have prematurely failed the batteries?