2 Batteries, 1 Bank Charger. How to charge?

I've had my boat for about a month now and I'm working out the bugs little by little.

I have 2 batteries, a Blue Sea 1, 2, both, off switch, and a Guest 6amp 1 bank charger.

The charger is wired to the starboard battery only. Can I splice into the '+' lead of the charger and connect it to the port battery? Will this work properly, and safely?

thanks!!!

Re: 2 Batteries, 1 Bank Charger. How to charge?

Bump...

This is the GUEST Charger Manual. I have the single bank model #2608A.

Re: 2 Batteries, 1 Bank Charger. How to charge?

More than likely you are going to have to charge them one at a time like it were a regular battery charger. If it is enough amps, you may be able to splice it to both, but it would still be faster to do them one at a time.

Re: 2 Batteries, 1 Bank Charger. How to charge?

Not worried about charging quickly. As just don't want to get down in the engine bay to switch the cables when one is done. Charging batteries slow will create less heat anyways right?

I just want some sort approval from the experts around here before I do this and a quick how to.

THanks for the reply.

Re: 2 Batteries, 1 Bank Charger. How to charge?

Since you have a switch, connect the charger POS lead to the COM terminal on the switch. The NEG lead goes to the neg terminal on either battery. You would then be able to charge either or both batteries depending on how you have the switch set. None of them would charge if you set the switch to OFF however.

Re: 2 Batteries, 1 Bank Charger. How to charge?

Silvertip, thanks for the quick response. I want to be able to hook my shore power and forget about it until I go out again. I'd rather not go back and switch. I could leave it on both but I have not check to see if I have a constant drain from systmes yet with the switch on both.

Is it possible to splice the '+' on the charger and run a '+' to each battery and the single '-' to ether battery?

Re: 2 Batteries, 1 Bank Charger. How to charge?

Certainly -- you can feed any number of batteries in that fashion. But the output of the charger is now required to feed two batteries, not one so the time to charge both would be double (assuming they were both discharged to the same degree).

Re: 2 Batteries, 1 Bank Charger. How to charge?

If you splice it together are you not basically tying the 2 batteries together and defeating the purpose of the switch, also what happens if one battery develops a problem, won't it also drag the other one down as well? I think the best solution would be to put in a 2 bank charger that has 2 separate outputs.

Re: 2 Batteries, 1 Bank Charger. How to charge?

Yes, the batteries are paralleled -- but they are being charged, not discharged. If the charger is not plugged in, then yes, a bad battery can suck the life out of the good battery until the two are equal. That can be easily solved however by inserting a simple diode in each of the POSITIVE charger leads. The batteries can therefore charge, but one cannot discharge the other.

Re: 2 Batteries, 1 Bank Charger. How to charge?

Silvertip said:

Yes, the batteries are paralleled -- but they are being charged, not discharged. If the charger is not plugged in, then yes, a bad battery can suck the life out of the good battery until the two are equal. That can be easily solved however by inserting a simple diode in each of the POSITIVE charger leads. The batteries can therefore charge, but one cannot discharge the other.

Click to expand...

What size diode would I need? Is this something I can pick up from Radio Shack?

Thanks!!

Re: 2 Batteries, 1 Bank Charger. How to charge?

The forward voltage needs to be 15 volts or higher and the current rating needs to be higher than the output of the charger. If its a 10A charger you need 10A diodes or greater. Depending on the Radio Shack store you visit, they may or may not stock them. I prefer the military or electronic surplus stores as they have good stuff, most of it heavy duty, and very well priced. It seems Radio Shack is getting out of the "component" business as they don't have any of the stuff I need anymore I consider my projects to be quite "garden variety". I've been buying sub-C nicad batteries from them for years and they no longer carry them. In fact the dude working in our local store didn't know what I was talking about.