Furuno RC-1800F2 Operator's Manual page 22

2. MAINTENANCE
2. Care of the battery
The lead-acid battery powers the radio console when the ship's main power fails,
to enable communication in the event of distress. Therefore, follow the points
mentioned below to keep the battery in good working order.
3. Confirming charging
Confirm that the BATTERY CHARGER switch on the Control Panel is set to AU-
TO. Further, confirm that the voltage shown on the voltmeter is normal (between
25.0 VDC and 28.0 VDC).
4. Use the hydrometer to check the specific gravity of electrolyte
Keep the specific gravity of electrolyte within 1.240 ± 0.010 (20 °C).
5. Water supply
The optimum electrolyte level is such that water fills to the highest graduation on
the scale at the side of the battery case. When the electrolyte level falls below the
highest graduation, fill to the highest graduation with distilled water. Do not use
diluted sulfuric acid or tap water; they will shorten battery life.
6. Cleaning
The battery and the area around it should always be clean and dry. Clean the bat-
tery case with a water-moistened cloth. Do not use organic solvents, thinner, gas-
oline, benzine or alcohol to clean the battery. (They may crack the case.) For
heavy dirt, clean the case with white kerosene.
7. Environmental condition
• Keep the battery out of direct sunlight.
• Coat the nuts and bolts which tighten the battery contacts with anticorrosive
paint. Check the battery once a year, retighten nuts and bolts if necessary.
2-4
WARNING WARNING
Keep sparks and lit smoking materials
away from the lead-acid battery. Make sure
the battery room is well ventilated.
The battery emits hydrogen gas which can
cause explosion.
The electrolyte in the lead-acid battery
contains sulfuric acid, which can be
harmful to the human body, particularly
to the eyes.
If sulfuric acid contacts eyes, skin or clothing,
flush directly with water. For eyes, contact a
physician. Loss of eyesight can result.
The temperature of the electrolyte in the
lead-acid battery should not exceed 45°C.
The electrolyte can cause explosion if it
becomes too hot.