The 12 Volt D.c. System - Figure - Tayana 37 Operation & Maintenance Manual

board generator. A modern yacht is highly dependent on these systems and it is
essential that they be maintained.
1. The 12 Volt D.C. System - Figure V.-2.)
The primary source of 12 volt power is the battery bank which comes with the yacht.
The battery(s) are used both to start the engine and to provide power for the various
electrical equipment on the yacht. The battery(s) are charged by the engine-mounted
alternator or by a battery charger (converter) which is connected to a 110 volt power
source.
Battery maintenance is simple but demanding - you should check your battery water at
least once a month whether you have sailed the yacht or not. This is particularly
important if you have a 110 volt converter or battery charger in operation. The
electrolyte (acid) level should be maintained to cover the plates in the battery. It is best
to use distilled water in your battery(s) but that is not totally necessary. Clean,
drinkable water can be used if distilled water is not available. NEVER USE SALT
WATER. Excessive need of water is an indication that the charging rate is too high. A
check of the charging voltage should not read over 15 volts. Should you spill
electrolyte from the battery, it should be neutralized with baking soda. Remember,
battery electrolyte is sulfuric acid which is very corrosive. It will eat into your skin,
wood, cloth, and some metals. Don't neglect a spill. If it gets on your skin, wash it off
immediately with soap and water. One other battery maintenance point is the two poles.
Make sure connections are clean and tight. A thin layer of grease will help keep battery
connections clear of corrosion.
The use of a hydrometer is an inexpensive and accurate measure of the battery's
condition. Specific gravity measurements of the electrolytes should read between 1.275
and 4.280 on a normally charged battery. All cells should read relatively equal; any one
cell that has noticeably low reading is an indication of a bad cell, and the battery should
be replaced.
V-19