Battery chargers

[SkunkBoat]

Sorry not liking that set up at all. I have a 3 battery, 3 bank, 3 battery switch system set up on my Grady. Bat 1 and 2 are for engines and set up with a 1-2-both switch each. Bat 3 is the house battery and separate from engine batteries and only has a on-off switch. All are connected to a negative buss. Primary charge lead from each engine charge the corresponding battery, the aux charge lead from one engine charges the house battery and the second aux lead from other engine does nothing. My charger is a Pro Mariner 3 bank 30 amp charger with a lead going to each individual battery. It is a distributive charger, meaning it can put all 30 amp to one battery if needed or divided up as needed, somehow it senses who needs what. I went from 2 house bats to one because I do not have any large draws on the system with my set up.

why not connect other aux to house? then it will charge if either motor is running.

 

[SkunkBoat]

The previous post concerning the different amperage levels on the ac and dc side of charging is very important. This is the basis for sizing wiring, fuses and connectors when setting up your system. The dc current may not electrocute you but faulty wiring or connections will sure arc or heat up and burn down your boat. I know a very handy farm boy in North Dakota that made a very functional arc welder from 3 old car batteries in parallel and some cable and clamps.

oh...it will electrocute you!

 

[dogdoc]

I thought I saw that was not a good idea, was I wrong. I do hate that orphan wire floating around in the transom.

 

[SkunkBoat]

So if I read what ProMariner said on my 282 Sailfish I could connect a 3 bank charger like in this image. Currently I have this old 2 bank Guest charger that is connected with one leg to each bank verses a leg to each battery and one leg does more AMPs than the other. I would see an issue with the two batteries that are connected for the House/STBD Engine legs conflicting with each other but the guy said they will not and can sense properly if I read this correctly. That is blowing my mind but learn something new everyday. I need to replace my charger and a lot more due to a lightning strike.
View attachment 14704

I have one set of charger leads to the parallel house bank. works fine. Promariner's instructions were to connect the leads on the pos terminal of one and the neg terminal of the other. This will account equally for the length of jumper wires.

 

[dogdoc]

I stand corrected, my only pathetic defense is the use of "may not" a less than absolute term. Reading on DC electrocutions was very interesting and I doubt I will ever be able to look at a car battery the same again!

 

[ayacht]

Sorry not liking that set up at all. I have a 3 battery, 3 bank, 3 battery switch system set up on my Grady. Bat 1 and 2 are for engines and set up with a 1-2-both switch each. Bat 3 is the house battery and separate from engine batteries and only has a on-off switch. All are connected to a negative buss. Primary charge lead from each engine charge the corresponding battery, the aux charge lead from one engine charges the house battery and the second aux lead from other engine does nothing. My charger is a Pro Mariner 3 bank 30 amp charger with a lead going to each individual battery. It is a distributive charger, meaning it can put all 30 amp to one battery if needed or divided up as needed, somehow it senses who needs what. I went from 2 house bats to one because I do not have any large draws on the system with my set up.

I agree it seems like a bad solution and it was from the factory that way in 2006. I may try to do something different. Your setup would be it except I would use a BEP distribution panel that allows either engine battery to charge the house battery.

 

[dogdoc]

can you send a link to that

 

[SkunkBoat]

can you send a link to that

here's what I did on my 265. Separated the House from the "1" Stbd Start battery and physically moved it to the port side with the port starting battery. then wired a two-battery house bank on the Stbd side. Put switches under the gunnels so I wouldn't have to remove bins every time I switched on/off. 3 bank charger and both aux chargers from the motors.
https://www.greatgrady.com/threads/new-battery-config-for-265.25744/

 

[dogdoc]

Can anyone verify that both aux charging wires can go to same battery? I may just have them go to a spare battery switch I have and then select which one will be used to charge the bank when running.

 

[ayacht]

Can anyone verify that both aux charging wires can go to same battery? I may just have them go to a spare battery switch I have and then select which one will be used to charge the bank when running.

I just had this conversation last night with a Yamaha Tech and we determined that if you want the flexibility to use either engine for the charging. It needs to be on a switch of some sort so only one was charging the battery at a time. He also made the observation that you would want to add a separate volt gauge to tell you what that battery was at because it will not be part of the harness data was his thought.

 

[SkunkBoat]

I ran both aux wires from my OX66s to my house bank for two years. Worked like a charm. Now my Suzuki aux wires go there. Works like a charm.

The aux circiuts are just big diodes that allow current to flow toward the battery and not flow toward the motor. If you are worried that the may be some damage, think about what a BOTH position does on your existing switches. It connects two motors to the battery. It charges those batteries thru the starter cable.

Most gradys used two parallel batteries on the stbd side as the stbd starting battery and house. In that case, the stbd volt readout from the motor would tell you what the HOUSE voltage is. In a case like mine, I do not use either starting battery as the House so the motor gauges don't show me House voltage just starting battery voltages. I can see the House voltage on every piece of electronics I have.