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SvHow many batteries do I need?
How to customise your battery bank according to consumption
For many boats, the dream of cruising around the archipelago for a week without running out of electricity seems unattainable. We know how to do it!
B+ goes to positive on the batteries (preferably via a main fuse).
B- goes to the negative of the batteries and the starter motor and any earth points.
D+ receives a magnetising current when the generator starts.
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 reasonably large bank with a daily discharge of 25 per cent, you will be able to oscillate in equilibrium between 60 and 85 per cent using only your generator. If you install a small solar panel too, the curve moves up a bit. That’s even better for the batteries.
If you have a poor connection, more batteries won’t help
A large battery bank will help for the first few days even if your charging is poor. However, bad connections, scarred cables or faulty diodes can leave you at dangerously low levels after just a few days.
So if you decide to just spend money on a large battery bank, it can be a costly affair as the lifespan of the batteries can be short if the charging does not work properly.
