This List of information is provided by us as general knowledge and is used at your own risk. The two below booklets are a GREAT read
Energy Unlimited and Wiring Unlimited
Electricity plays an increasing role on board yachts. Modern navigation and communication equipment depends on it, as well as the growing list of household appliances that are taken on board.
This Chart for 6, 12, 24, and 48 volts shows you the State of charge for the battery bank based on the voltage, This is always very accurate it tells you when the bank is full or partly discharged based on the CURRENT available ACTIVE PLATE area in the battery (active plate area means the usable area or what's left of the active material as the battery ages there is less and less active material available), as long as you have let the battery bank be at rest for a min of 30 min, Keep in mind that if your battery banks voltage is say 12.9 when fully charged then adjust these tables by adding 0.2 volts to them, the fully charged voltage can vary depending on the chemistry used in the battery.
Never mix old batteries with new or different types of batteries
Over the Years Octopus Electrical has found information that is of general interest to customers on electrical points. have a look and see if anything is of help to you.