SEALINE S28, Owner'S Manual

Page: 12 / 61

Sealine International Ltd. (V1.1)
Page 12 of 61
Electrical Systems
BATTERY CHARGING
General
The battery charger fitted is a 12V 40A device capable of keeping all the batteries in a good state of charge. When
the battery charger is not in use and the engines are running the engine alternators maintain the batteries and 12V
systems.
Main Panel Display
The 12V DC section of the AC/DC panel displays all the relevant information you need to keep your batteries in a
fully charged state; all that is required is a little understanding. By turning the main isolator switches to the "on"
position the voltage display will indicate the starboard/auxiliary battery voltage level. The port engine battery
voltage can be obtained from the engine voltmeter on the dashboard.
Next to the voltage display is the Amp Meter, which indicates (when the engine is not running), whether the 12V
system is charging (green) or discharging (red).
The idea of the display and battery charger is best-described using water as a medium. If you imagine your
batteries as a reservoir, and your battery charger as the water topping it up you will have a certain amount of
surplus when your reservoir is full (batteries fully charged). This surplus will be used up when your auxiliary circuits
are in use.
The battery charger is not an endless source of DC power, when you are using a lot of your auxiliary circuits the
display will fall into the red. This is when you are emptying your reservoir (discharging auxiliary batteries). This, in
normal use, will be topped up when you are using less auxiliary circuits (display in the green).
Prolonged use with the display in the red will lead to flat batteries. When shore power is not available, your
starboard engine will take care of auxiliary battery charging. To recharge these batteries will take some time
provided that auxiliary circuits are used to a minimum. Should you discharge your batteries to an extent that you
are unable to start your starboard engine, firstly start the port engine then press and hold the battery link switch to
start the starboard engine.
Engine Charging System
The 12V DC system has one (two for electronic engine) battery for starting the port engine and three (two for
electronic engine) batteries for starting the starboard engine and running auxiliary equipment.
The port engine charges its own batteries.
The starboard engine charges the starboard/ auxiliary batteries.
The port and starboard battery banks are independent. There is no link for charging.
Battery Link Solenoid
Should one of your battery banks become discharged and you are unable to start
one of the engines, you should first start whichever engine has good batteries.
Press and hold the battery link push button and at the same time start the other engine.
BATTERIES
General
In order to supply auxiliary circuits, ignition, starter motor etc., you need an efficient reliable constant source of
energy. To achieve this a little understanding and care is needed. The battery is not an inert object, it leads a highly
interesting electrochemical life.
Battery Self Discharge
Any charged battery left standing, gradually loses its charge, this is unavoidable. The average rate of discharge is
about 1% of the capacity per week. This can be more if batteries are not cleaned. Taking this into consideration, if
you are leaving your boat for a long time, such as winterising, some maintenance is required.