Trojan Boat Forum

I have decieded to update my electrical system as it no longer supports my needs for extended stays on board. I am not sure I have this right but here is my plan. Any input from the electrical nerds here is fully appreciated.

I want to add a 3rd battery bank, so I will have 2 start batteries, one dedicated to each engine and 2 house batteries in parralel to increase my amp hours. These will all be maintenece free AGM's.

I have purchased a Pro Mariner Proisocharge, 2 alternator 4 battery bank isolator so I can charge my 3 banks off my 2 70amp alternators while running. I installed new alternators last year in preparation for this.

http://www.promariner.com/en/products/p ... rge-series

I also purchased, because of good reviews on this forum and others, the Pro Mariner 1240P battery charger.

http://www.promariner.com/en/63140

The below diagram is my amatuer attempt to work this out. I realize there are two things missing in my drawing... maybe more. 1, I need the ignition start leads to go to the isocharge. 2, I need to be able to combine my starting batteries in case of an emergency.

I know there are allot of ways to go about this, Blue Sea Systems makes a nice package for this also. So, am I over thinking this, is there a better way? or am I on the right track. Any help by those that have done this is appreciated.

WARNING! PLEASE DO NOT ATTEMPT TO USE THIS AS A GUIDE FOR YOUR INSTALLATION, it is strictly conceptual and not a working system.

Maybe some breakers on the battery positives?
https://www.amazon.com/gp/product/B01F7 ... UTF8&psc=1

Yup, those are the swiggley lines under the on/off switches.

Nice drawing, heh If you are going with all new cable/wiring here there are two things that come to mind, don't combine grounds, like from your inverter and house bank to the bus. The other is why did you pick the 40 amp charger, this is one place where bigger is much better when considering recharge times from your genny. That way if you decide to go to a larger bank then all is well.

I would stick to wet batteries, a little maintenance is a good thing IMO, gets you looking at stuff, whatever you choose keep them all the same type....MIke

Food for thought:

If ur redoing the DC, consider adding an inverter. I can run my fridge from my inverter while underway, no genny req'd. Once alternators replace the starting charge, they are available to do other work, making my beer much colder than WayWeGo's when I get to my destination.

Consider an inverter/charger. I have separate, cuz I did charger first. Outright replacement to be rid of my buzz box.

Study the discharge characteristics of the batteries that you are considering, particularly the effect of discharge depth on life. Lots of good info in nigel calder's "boatowners mechanical n electrical handbook." Also includes treatise on inverters. Ought to be required reading for every boat owner.

Buy a hydraulic terminal crimper.

Genuinedealz is a decent source for wiring products.

Use adhesive lined shrink tubing over terminals.

I have a label maker. I labelled each wire at each end with a label, and at strategic points in between. Then i put a piece of clear shrink tubing over the label to protect it.

Good luck!

Looks good.
It's best to minimize the number of connections at battery posts. On that note, rather than connecting charge wires at the batteries, connect them to the source side of each battery switch. The only charger lead going to an actual battery is the temp probe. I would connect it to the house bank. Each charge wire will also need to be fused, and you'll need to run a chassis ground on the charger. If you're going to fuse the alternator output, I recommend doing it between the alternators and the isolator.

It won't hurt but there's no need to have battery switches for each bank leading to the isolator though you should install them between the battery and the loads; engines and breaker panel.

Many ways to skin a cat when it comes to combining banks. You can install one of the more expensive options, or a simple sealed solenoid, and a momentary switch located at the helm will do the same thing much cheaper.

As far as combining the starter banks you should have Trojan emergency start system already . If its missing or inop you can install a sealed solenoid like Big D said . It should be wired so either battery can power the solenoid as needed . ( A dead Battery wont work a solenoid )

Fishblues wrote: ↑Sat Mar 02, 2019 3:26 pm Yup, those are the swiggley lines under the on/off switches.

Looks like a solid line from the battery to the inverter.

P-Dogg wrote: ↑Sat Mar 02, 2019 5:12 pm If ur redoing the DC, consider adding an inverter. I can run my fridge from my inverter while underway, no genny req'd. Once alternators replace the starting charge, they are available to do other work, making my beer much colder than WayWeGo's when I get to my destination.

You mean I have been wasting good money on dry ice???

ABYC recommends circuit protection within 7" of a battery except in special configurations: http://assets.bluesea.com/files/resourc ... cerpts.pdf

I just run the genset , all drinks are cold and so is the Cabin


Fishblues
You should have the inverter on the other side of the Battery switch(s) so it kills the power to it

Thanks for the input everyone, it is very much appreciated.

FYI, I have no generator and don't want one. As long as I can power my coffee machine in the am, a small TV and my refrigerator I am a happy camper!

mikeanddanna, your right, I do need to run the inverter ground straight to the negative bus bar. But I think my 40 amp charger will be sufficient. I am still a working man so I am mainly out on the weekends, so the charger has plenty of time to recharge the batteries.

BigD, Promariner explicitly states that the battery charger terminals go straight to the battery banks.I wanted to run them off the isolator to save me some wire runs but that was a no no.

Prowler, ABYC standards state that I need those emergency shut offs right after the isolator on each battery, and also fused. Unless I read that wrong.
I have been trying to follow them to the letter.

My Trojan emergency solenoid is inop. So I guess I am going to use this for my emergency start battery combiner with a switch somewhere.

https://www.bluesea.com/products/9012/L ... 4V_DC_250A

On another note my end goal is to add a solar panel at some point on my hardtop, but I have spent my allowance for this year on the electrical system

Cool, watch the fuses as some cannot be used in a gasoline engine compartment, tough to comply with, I believe blue seas may have something for that now.

mikeandanne wrote: ↑Mon Mar 04, 2019 5:31 pm Cool, watch the fuses as some cannot be used in a gasoline engine compartment, tough to comply with, I believe blue seas may have something for that now.

Excellent thought, thank you. I am posting links just in case anyone needs the info down the road. These should work perfect,

https://www.bluesea.com/products/7720/A ... Fuse_Block

Fishblues wrote: ↑Mon Mar 04, 2019 3:20 pm.....
BigD, Promariner explicitly states that the battery charger terminals go straight to the battery banks.I wanted to run them off the isolator to save me some wire runs but that was a no no.....

Interesting, I've installed countless ProNauticP units and do not recall the manual specifically stating that hookup directly to the battery terminals is a must. That would be front and center and very clearly stated as are the other important precautions if that were the case. Their diagrams are set up that way but most likely for simplicity given that there are numerous ways to accomplish the same thing. Electrically it shouldn't matter as long as the connections are good, secure, clean, etc. The one that must specifically be connected to a battery terminal is the temp probe. I will check but I'm pretty sure I'm remembering the hookup correctly. You may want to reread carefully. I think you'll find that it refers to hook up in general terms and not a must to where they specifically must hook up.

Most OEMs now do not go to the batteries as this has a few benefits. One is that you can disconnect the batteries for winter layup as an example but still power up the ship's DC systems by plugging into shore power and turning the charger on. Where boats have powered engine hatches, they'll either have an external battery bypass hookup in the cockpit for powering up the hatch when batteries are disconnected or simply plug the boat into AC with the charger on. With batteries disconnected, it's the only way to get the hatch down after the disconnect or up to reconnect. With the charge wires hooked up to the batteries, this wouldn't be possible.

mikeandanne wrote: ↑Mon Mar 04, 2019 5:31 pm ...watch the fuses as some cannot be used in a gasoline engine compartment,...

You can use ATO fuses but get the in-line waterproof holders that can be fastened to a panel or wall. Except for specific engine mounted fuses and breakers, I don't know of any other fuses except the ANL fuse that is specifically rated as being safe to use in a gasoline engine compartment. Others can be used but must be in a holder that offers protection.