Lithium Pros wiring with Jump switch

[toofy]

First my question, then I'll explain: With my setup, can I turn on the "Jump" switch when I'm running on the big motor and will it charge both my 12 batteries? And will the DC charger wait for both 12v batteries to top off before charging the 36v?

I have two Lithium Pros 36v batteries wired in parallel for the trolling motor. Then I have two 12 Lithium Pros. One is the starting battery and the other is the "house" battery for electronics. I have 2 stealth chargers to plug up to the garage wall at home, and one 36v DC charger from Lithium Pros to charge the 36v trolling batteries while running on the big motor. This was wired up at the dealer since I'm not smart enough to figure this out.

The reason for asking is that I have had 2 long days where the house battery went dead. 3 graphs, livewell, power poles, radio, etc.

I traced the wiring out and drew a diagram in case it matters. The Lithium Pros DC charger is the box in the middle:

[John Jackson]

I'm not sure I understand your schematic, but I don't like the grounds being tied together. You didn't say what motor you are running. Some Yamaha's aren't compatible.
Why not run the 12V in parallel. Doubles cranking and reserve amps, and both charged when running the motor.

[Joe4d]

Now without actually looking at things kinda guessing at this. But in my experience things designed to do a certain thing, tend to do that thing pretty well. (IE ur Jump switch probably jumps well)and not do other things well. Like charge and be left on all the time. Problem I could forsee would be motor battery draining into low house battery faster than it charges and on a short run u end up with 2 batteries that cant crank ur engine.
There are actually quite a few products out there that can do what u want, will charge ur second battery OFF your motor, but not until after ur motor battery is full, and it only allows current flow one way. Wont discharge ur motor battery. Talk to Stealth since you are using their products. They are all over this stuff.

[Lou r Pitcher]

Grounds being made common are very necessary for devices being used.

Jumping is intended for emergency use.......never a good policy on possibly combining very dis-similarly discharged batteries suddenly in parallel as very high damaging amps can flow from charged into discharged one.

Some outboards can be damaged as well by using a jump switch while engine is running.

[Jonestrollingmotor]

You have grounds coming off the Jump switch. There is no ground on the jump switch. The jump switch will have one side to one battery, the other side to the second battery and the center to the appliance. Properly set up, the positive will go as I stated, the two batteries (main and second) will be connected together with the grounds. I would not attempt to jump any 12V battery from a 36V system -- which it looks to me like you're trying to do.
John

[toofy]

You have grounds coming off the Jump switch. There is no ground on the jump switch. The jump switch will have one side to one battery, the other side to the second battery and the center to the appliance. Properly set up, the positive will go as I stated, the two batteries (main and second) will be connected together with the grounds. I would not attempt to jump any 12V battery from a 36V system -- which it looks to me like you're trying to do.
John

I don't think the 36v batteries are jumping the 12v batteries. That middle square is the DC charger from Lithium Pros. It has a red wire, a yellow wire, and 2 orange wires. The orange wires merge into 1 wire I think. I tried to color those in the photo and maybe that's why some of it doesn't make since to those not familiar with the DC charger.
It's actually more complex because I also have a Victron battery monitor in the chain. https://www.victronenergy.com/panel-.../bmv-712-smart
There are lots more wires but I can't tell where many of them go because they travel way out under the back deck. I think some go to the motor (Evinrude 250 G2) and some probably go forward to the electronics.

I just wish I had a way to charge the house battery while running. The starter battery is always 95-100% full and tops off within 5 minutes of running. I may call the Stealth guy since he told my dealer how to set it up.

[Lou r Pitcher]

I just wish I had a way to charge the house battery while running. The starter battery is always 95-100% full and tops off within 5 minutes of running. .

If you are running an Evinrude ETEC, then your wishes can be easily met by using the AUX charging output to charge your house battery providing it with a dedicated and regulated charge current up to 25 amps.

[toofy]

If you are running an Evinrude ETEC, then your wishes can be easily met by using the AUX charging output to charge your house battery providing it with a dedicated and regulated charge current up to 25 amps.

Interesting, I didn't know my motor had that. That would definitely involve me going back to the dealer to see if they could set that up.

[Marshfly]

Interesting, I didn't know my motor had that. That would definitely involve me going back to the dealer to see if they could set that up.

For those with other engines, most larger engines made in the last few years have this capability. I know my SHO does as did the F150 on my last boat.

[Marshfly]

I just wish I had a way to charge the house battery while running. The starter battery is always 95-100% full and tops off within 5 minutes of running. I may call the Stealth guy since he told my dealer how to set it up.

If this is all you want to do then just install a Blue Sea ACR. Easy, reliable, and no snaking wiring through the rigging tube.

[Jonestrollingmotor]

I do see what you're saying, however I don't think the equipment in between the two batteries "dividing" the 36V into 12V. I think it is probably taking a 12V input and increasing to a 36+V output to charge the battery. This would concern me trying to jump through this type equipment. If you're trying to charge the house battery, simply connect the selector switch to the house battery and the cranking battery with 4ga wire, run a ground 4ga ground between the house and cranking, then set the selector switch to both and it will charge and run off both batteries.

[toofy]

If this is all you want to do then just install a Blue Sea ACR. Easy, reliable, and no snaking wiring through the rigging tube.

I looked it up and it looks interesting. I wonder how I can find out if this will work with Lithium batteries?

[toofy]

I do see what you're saying, however I don't think the equipment in between the two batteries "dividing" the 36V into 12V. I think it is probably taking a 12V input and increasing to a 36+V output to charge the battery. This would concern me trying to jump through this type equipment. If you're trying to charge the house battery, simply connect the selector switch to the house battery and the cranking battery with 4ga wire, run a ground 4ga ground between the house and cranking, then set the selector switch to both and it will charge and run off both batteries.

The 36v batteries are not linked to the 12s. There are two 12v batteries and two 36v batteries. I probably should have left the 36v batteries and that DC charger out of the picture.

[Jonestrollingmotor]

initial post: First my question, then I'll explain: With my setup, can I turn on the "Jump" switch when I'm running on the big motor and will it charge both my 12 batteries? And will the DC charger wait for both 12v batteries to top off before charging the 36v?---
The 36v batteries are not linked to the 12s. There are two 12v batteries and two 36v batteries. I probably should have left the 36v batteries and that DC charger out of the picture.

Ok, sorry about misreading the initial post. I thought you were asking if the jump start switch would allow you to jump from the trolling batteries. The problem I see now with the jump switch is your showing a ground wire going to the house, cranking and Lithiums coming off the switch. As I stated earlier, there should be no ground wire on the switch. The three wires would be battery 1 positive, battery 2 positive, and the common where the accessories and outboard would be connected. If there is 4 ga wire used there and 4ga is used to jump from negative of cranking to negative of house, then setting the switch to "both" will charge both batteries and allow the outboard to start off both batteries. DC chargers usually monitor the cranking battery (and if yours is set to both, then it thinks it is one large battery) and once it reaches charge, it will begin to charge trolling batteries.

[toofy]

Thanks for the explanation. Dumb question: the switch common wire that goes to the accessories....shouldn't that be to the negative of the accessories? If so, those negatives are connected to the negatives of the battery so how is that different from what I have drawn here?

[Jonestrollingmotor]

Thanks for the explanation. Dumb question: the switch common wire that goes to the accessories....shouldn't that be to the negative of the accessories? If so, those negatives are connected to the negatives of the battery so how is that different from what I have drawn here?

No, that (the common on the switch) will go to the positive of the accessories. The negative of the accessories will go to battery ground. The grounds being tied together, it can go to either ground.



Hope this helps.
John

[toofy]

Thanks for taking the time to draw that and explain. I'll have to look at my wiring again to make sure I traced everything out correctly.

[Hickory Legend]

I would call Kevin at lithium Pro and Danny at Stealth one for the correct set up. Looks like when you swap to jump your running parallel. So with their approval, might want to just run them that way and use the switch as a cut off to kill the boat when not fishing.

But see what they think is the best way, might be you have a week house battery.

[proptwister]

I'm running this exact setup. Yes, you can start the motor like normal and then switch your Perko switch to "both" to charge the house battery. I'm running a 100 Ah house battery and have never ran it dead but I'm not running power poles either. I've got the wiring diagram from Danny that I'll try to post. And yes, its vital that ALL grounds, regardless of voltage, are tied together.

[toofy]

Good insight from everyone!