HOW TO SELECT YOUR BATTERY
The use should dictate your choice :
// Board lighting, radio, various electronic equipment
Add up the consumption of every equipment (multiply the powerby the number of hours in use).
• Cabin lights : 3 lights, 10 Watt for 6 hours = 180 Wh
• Electronic equipment : 100 Watt for 8 hours = 800 Wh
• Navigation lights : 40 Watt for 8 hours = 320 Wh
TOTAL CONSUMPTION = 1300 Wh
With a 12 Volt battery, the consumption is 1300/12 = 108 Ah.
As a battery must not be discharged beyond 20 %
of its nominal capacity, the capacity of the battery should not be
lower than 108/0.8 = 135 Ah (140 Ah battery).
// Starting outboard and inboard engines
The choice of the battery is subject to its cold start performance.
// Combined use of domestic application and engine
The energy required to start the engine is negligible compared to the power requirements of the other electrical equipment on board. When selecting the battery capacity, it is therefore necessary to consider the consumption of these appliances, and then to double check that the maximum start-up intensity is sufficient for the engine.