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SvHow many batteries do I need?
How to customise your battery bank according to consumption
In many boats, the dream of cruising around the archipelago for a week without the power running out feels unattainable. We know how you can do it!
B+ goes to positive on the batteries (via a main fuse).
B- goes to the negative of the batteries and the starter motor and any earth points.
D+ receives a magnetizing current when the generator is to start.
Some generators also have W which is the tachometer socket and DF which is in direct contact with the magnetising winding of the rotor.
Why a large battery bank is not always the solution
If you have a suitably sized bank with a daily discharge of 25 percent, you will be able to oscillate in equilibrium between 60 and 85 percent using only your generator. If you also install a small solar panel, the curve shifts up a bit. That is even better for the batteries.
If you have poor connections, more batteries will not help.
A large battery bank helps during the first few days even if your charging works poorly. However, bad connections, corroded cables, or faulty isolator diodes mean that after just a few days you will be down at dangerously low levels.
So if you choose to spend money only on a large battery bank, it can become an expensive affair, as the lifespan of the batteries can be short if the charging does not work as it should.
