Upgrading Charging System

[nigel1]

Planning on upgrading the boats battery charging system, and would like some advise/opinions on my preliminary plans.

The original set up from the factory was a Dolphin 2 output battery charger, with one output connected to the house switch and one to the engine start switch. The battery switches are wire in such a way as that when both house and start switches are put to the on position, the two banks are combined. See the attached diagram from the owners manual.
From the drawing, it looks like the alternator will charge both banks when both switches are in the on position, if not, it will only charge the start battery



Prior to me buying the boat, the PO fitted a vetus bow thruster, powered by 2 x 110Ah batteris located in the forward berth (not ideal). These batteries are not connected to the shore battery charger, and from what I can see, the installers fitted a split charge diode on the alternator output, with outputs to house, start and bow thruster banks.

Plans are to
1) Install 270 watts of solar, which will be set up to only charge the house bank
2) Fit a Sterling Pro Charge 60 amp 3 stage charger with 3 outputs. This charger also has an equalisation facility.


I will connect two outputs from the charger direct to the battery posts of the house and engine start batteries, or maybe follow the factory idea, and connect to the switches.
With respect to the bow thrust batteries, could I connect the third output from the battery charger to the output side of the split diode going to the BT batteries, or is this bad practise, and I should really run a cable the full length of the boat from battery charger to bow thrust batteries (a distance of about 42 feet)

Is there any sense in putting isolating switches (on/off) in the output side of the battery charger cables?.
For example, I may think that the bow thrust batteries need a good equalisation charge, but theother banks do not, so I could isolate them from the charger, and just put the equalisation charge to the bow thrust bank only, or am I over engineering this?

I really do need to upgrade the system, but don’t want to go overboard with unnecessary stuff, so any help from the electrical experts would be most welcome

Cheers

[skipmac]

Don't think anyone would call me an expert but I do have some opinions and suggestions. Also, after a lot of thought and research these suggestions will be how I am setting up my system.

Battery Banks - one bank for house power, all batteries hooked together so all provide power and all are charged together. Then one isolated starting battery.

Charging

1. To charge the starting battery the easiest and most completely idiotproof method is to add an automatic battery combiner like made by Yandina, Blueseas and others. It is an automatic switch that only engages when there is charging voltage to the house battery bank. Only when the house batteries are charging the switch connects the start battery. When charging stop the switch opens and your start battery is isolated and protected.

2. All charging sources, alternator, solar, wind, should be connected directly to the house batteries BUT protected by inline fuses.

With these two features you never have to remember to turn any switches or change anything to charge the house batteries and protect the start battery.

3. multi bank charger. With the setup described about you only need one charging output. Save money, simplify wiring.

Wiring - with two master switches, On-Off and 1-2-Both-Off you can wire the system so you can use the house battery for emergency starting or the start battery for emergency house power. The diagram to do this is posted in a previous thread.

[Paul L]

How big a house battery bank, ah? What is the alternator output? Do you also have a generator?

[nigel1]

Originally Posted by Paul L

How big a house battery bank, ah? What is the alternator output? Do you also have a generator?

House bank will be about 420 Ah 12 V.
No genset, but a D400 wind geny cionnected to house bank, plus 270Watt solar to be installed to house bank.
Alternator, dont know, its the standard unit supplied on a Volvo Penta tmd22, doubt if it will be anything special

[Paul L]

Without a genset the charger will only be used at a dock. I assume you are setting this up to cruise with lots of anchoring. I'd make sure 60 amp charger will work with a Honda/Yamaha 2000 gas (petrol) portable gen. You may end up with one. If you are thinking of adding a diesel genset in the future, then I'd go with a bigger charger. 420ah is not a lot for a 47 boat. I'd consider upgrading the alternator to a high output one, 120 amp or so and getting an external regulator. That way you can bulk charge the batteries with the alternator and then let the solar take them back to 100%. You may think that 270w solar is a lot, but with refrigeration in the tropics it will add a lot to your energy, but is not likely to keep up 100%.

[Irish rambler]

I would respectfully suggest you contact sales@adverc.co.uk if you give them all the details of your system they will calculate a solution for you, they were in this field long before sterling and their system are used by Police,Ambulance services etc. Your contact is Brian.
Hope this helps.

[nigel1]

Now most of the way through sorting out the charging system.
Installed a 60 amp Sterling charger, a no volt loss splitter, Adverc regulator. Replace the original undersized cables with AWG 3 and AWG 0 cables.

Left to do is the solar panels and the Blue Sky 3024 solar controller.
Considering a IPN Pro-remote to go with the solar controller, allow me to adjust settings. Now, if I fit a 50mV 500A shunt, I can also use the Pro Remote as a battery monitor.
I already have a monitor (NASA BM1) which uses a 50mV 100A shunt.
Is it possible to put the two shunts in series, and allow both monitors to function correctly. If not, I'll just leave out the second shunt and use the Pro-Remote as a controller only.

[beebopbogo]

If it helps, maybe the system on my Cal 39 sailboat can supply a few ideas.

Electrical Diagrams | Sailor's Life For Me

Granted, it's a bit complicated for my liking (separates the system into 3 battery banks, uses solar, wind, alternator and shore power) but it's 100% automated so no need to flip flop any switches.

When charging, all batteries are connected automatically using a Blue Sea charging relay and a Newmar battery integrator.

When not charging, all banks are automatically isolated (Eng, House 1 and House 2).

Battery switches allow many options. I normally leave House 1 and House 2 connected, but I can separate them and monitor with the Heart Interface Link 2000. That way, if one of my AGM 105 Ah batteries goes bad I will be able to see the draw and isolate the bad bank with the flip of a switch.

For the past 2 years it's worked smoothly, but as I say, it is quite a complicated system for a 40 foot sailboat.

[Nlarsin01]

What I did was set up the usual 2 banks with 3 on off switchs one for the house one for starting one to combine. Also one near the inverter/charged as a quick disconnect.
I put all charging sources directly to the house bank and used an echo charge to keep the starting battery charged. The echo chage is the best dc to dc charger on the market its regulated and charges up to 15amps. It only charges when it senses 13v or more. Simple installation only 3 wires.
For the bow thrusters you just have to run 2/0 cable up to them from the house and with some switches make them do double duty with the windlass.
Leese Neville make some nice alternators with built in 3 stage regulators. I put on the 210 amp model double pulley then fused it with an ANL fuse.
I got my supply's and advise from acdcmarineinc.com