Power Management

[chicodesouza]

I'm new to the forum and want to give my congratulations to everyone!
Not long ago I bought my first sailboat (32 feet) and I'm redoing all the electrical part.

I'm trying to figure out the best way to make the management and control of load and consumption of batteries, preventing loss and overcharging.

The whole electrical system is 12V dc.

I have 4 power sources:
- Engine 29hp Yanmmar
- A solar panel
- A wind generator
- Source of land (equipment not yet installed)
I have 3 battery banks
- Lights and electronics (2 batteries)
- Refrigerator (2 batteries)
- Engine start (1 battery)

Could someone help me indicating what equipment should I buy to make this control and management and how to connect them?

Sorry about my poor english. I hope you understood my question
Thank you in advance

[CSY Man]

What size alternator, what size solar panels, etc..?

[chicodesouza]

Sorry about that!
- Engine Alternator: 80A @12V
- Solar Panel: 46 Watts - 3.8A @12V
- Wind Generator: 250 Watts at 24.3 knots (12.5 m/s) - 20.8A @12V
- Land Source: not yet selected (appreciate suggestions)

Batteries: I will change all, but probably about 150Ah (maybe 220Ah) each

Thanks

[DeepFrz]

First of all combine your house and your refrigeration batteries into one bank. If you use the Google search engine under the search tab you will get lots of threads on wiring and equipment set up.

[chicodesouza]

Hi DeepFrz, I tried use Google Search, but unfortunately did not come to any conclusion. Really I am a beginner!

[DeepFrz]

Try "rewiring a boat" or "boat rewiring".

[roland stockham]

OK, this may be a big job or not but there are lots of decisions that need to be made logically. First a few;
How old is the current wiring?
Is it plain copper or tinned (if you are not sure trim the insulation back and see - copper colour = plain copper; silver = tinned black/dark green = dead, it was copper now corroded!!!
What standard was it built to - a few good guides are to look at the size of main cables and take some measurments. a key one is the cable from the alternator to batteries if it is light wt and drops more than 1v at max charge then it mag be doing it's job poorly. Look at some connections. Good ones seal between the wire cover and the terminal, bad one are plain crimps.
Having looked at all this you have to decide if you are replacing the coplete system with all wires including mast wiring, just some areas or just the main power cabling.
The next step s to do drawings. You need to have a good diagram of anything that is there and being left in place.
So now you have an idea of the job and a map of whats already there. Time for decision
What is the boat used for? cruising/racing/ocean/weekend. That really effects what you do. A race boat does not want heavy batteries. An ocean boat or live-aboard needs very good charging systems and hefty batteries.
No you design the system, AGM or wet cell batteries, basic 1 2 both battery switch or diodes. Standard charger or alternator regulator. LED or filament bulbs?
You may be getting lost at this point which is understandable. Modern boat electrics are highly complex systems and if well done all the design elements interact to give a reliable and efficient result. With a little experience and a LOT of reading it is perfectly possible to design and build you own system but it is far more complex than a house. In a house you just hook up consumers. In a boat you build the power station as well plus backup generator and then shack the whole lot hard in a salt water shower and expect it to keep working...

[Jimbo485]

Buy Nigel Calder's book and just do what he says.

[Dockhead]

Originally Posted by chicodesouza

I'm new to the forum and want to give my congratulations to everyone!
Not long ago I bought my first sailboat (32 feet) and I'm redoing all the electrical part.

I'm trying to figure out the best way to make the management and control of load and consumption of batteries, preventing loss and overcharging.

The whole electrical system is 12V dc.

I have 4 power sources:
- Engine 29hp Yanmmar
- A solar panel
- A wind generator
- Source of land (equipment not yet installed)
I have 3 battery banks
- Lights and electronics (2 batteries)
- Refrigerator (2 batteries)
- Engine start (1 battery)

Could someone help me indicating what equipment should I buy to make this control and management and how to connect them?

Sorry about my poor english. I hope you understood my question
Thank you in advance

It would be helpful to know what kind of consumption you have on board, and whether the solar and wind more or less keep up with it or not. If you have light consumption which is mostly covered by solar and wind, then your system may be simpler, than if that is not the case. Do you have an inverter?

In general, as has already been suggested, do by all means combine refrigerator and house banks.

Some tips:

1. Keep start and house banks as separate as possible. Echo charge the start batt from the house bank, probably. Do not use a "1, 2, both" type switch. Don't run anything from the engine start bank except engine starter (and engine electronics, if any). Larger boats often have separate alternators altogether for house and start -- probably overkill for your application.

2. Have a good MPPT controller for your solar and wind.

3. Use a battery monitor (NASA, Victron, etc.) to keep watch on your battery state and currents, but don't rely on the "% remaining" readout. Experienced sailors pay most attention to charging current and voltage and mostly discount the calculated "% remaining" value.

4. Buy a good multistage battery charger (Sterling, Mastervolt, Newmar, Victron, etc.) with charging capacity about 10% to maximum 15% of nominal battery capacity (that is, if you have 400 amp/hours of nominal battery capacity, you want a roughly 40 to 60 amp charger). If you're only using it with shore power -- that is, no on-board generator -- then you don't need bigger charging capacity than that. If you need AC power on board, a combine inverter/charger is a good idea. This will give you the added function of controlling the amount of power you take from shore power and boosting it with inverted power if needed.

5. If, however, your consumption is reasonably well covered by solar and wind, then it may be that you hardly need shore power charging.

6. Charging your start battery will require minimal power since you use a very small amount of the capacity of the battery every time you start the engine. So it's a great idea to install a separate, small, multistage shore power charger for the start battery. This helps keep everything as separate as possible between house and start banks.

7. Batteries should be matched to each other -- you're starting over with new, right? Choice of batteries is a whole separate topic outside of the scope of this -- see the archives for plenty of information. The very short version: don't use "leisure" type "semi deep discharge" batteries UNLESS you are on shore power nearly every night.

8. Don't let your batts -- whatever kind you have -- get below about 50% discharged. The deeper the discharge, the shorter their lives.

9. Very important: Use a good external regulator for your alternator -- like Balmar, Sterling, Adverc, etc. Without external regulation, car-type alternators do a poor job charging deep discharge battery banks.

10. Do a calculation of your consumption. If you're like most cruisers, refrigeration will be by far the biggest consumer. It is often possible to save large amounts of power by properly insulating your refrigerator. You can dramatically reduce power consumption for lighting by replacing incandescent with LED lights -- highly recommended.

Good luck, and let us know how you get on!

[chicodesouza]

　
Hello everybody!

Dockhead: I will study with detail and scalm your suggestions, I think that will be very useful. And so I come up with something conclusive post here with a diagram .

Jimbo485: I read three books (Charlie Wing , Don Caseys and Nigel Cawders ) , have been very useful but the question of the energy managment is not covered. Also did a lot of research on the web including search suggestions of fellow DeepFrz .

Roland Stockham: The boat is being used for weekends and periods of up to 10 days on board, but I intend to use it to the ocean.
I'm changing all the wiring except the mast that will change next year , but I checked and they are in good condition , I am also changing all lights for LEDs. I already have a partial diagram of the installation but has several other issues that I am still studying .
I not yet started the service because I'm worried about planning what might be the best thing to do . Especially avoid splices later.
I understand a little about electrical and electronics, but I know that sistyem in a boat is very different from what I'm used to seeing in homes or cars .
Solar and wind generators were already on the boat , so I'll keep them .

I am currently putting the management of energy in the first place because I live in Brazil and in approximately 10 days I'm going to US where I want to buy this equipment. In Brazil are extremely expensive and hard to find

Thanks to all
Regards