Komatsu 830E-AC Shop Manual page 235

BATTERY CHARGING SYSTEM
ELECTRICAL SYSTEM DESCRIPTION
The Komatsu truck utilizes a 24VDC electrical sys-
tem which supplies power for all non-propulsion elec-
trical components. The 24VDC power is supplied by
two pairs of 12-Volt storage batteries wired in series.
The batteries are a lead-acid type, each containing
six 2-Volt cells. With the key switch on and the
engine off, power is supplied by the batteries. When
the engine is operating, the electrical power (non-
propulsion) is supplied by a 28-Volt alternator. Refer
to Schematics, Section R, for specific electrical hook-
up information.
CHARGE VOLT AND AMP VALUES
The volt and amp levels are a function of the battery
state-of-charge. If the batteries are in a state of dis-
charge, as after extended cranking time to start the
engine, system voltage, when measured after the
engine is started, will be lower than the regulator set
point. The system amperage will also be high. This is
a normal condition for the charging system. The
measured values of system Volts and amps will
depend on the level of battery discharge. In other
words, the greater the battery discharge level, the
lower the system Volts and the higher the system
amperage will be. The Volt and amp readings will
change; system Volts reading will increase up to the
regulator set point and the system amperage will
decrease to a low level (depending on other loads)
as the batteries recover and become fully charged.
BATTERY
During operation, the storage batteries function as an
electrochemical device for converting chemical
energy into the electrical energy required for operat-
ing the accessories when the engine is off.
D10003 07/06
BATTERY CHARGING SYSTEM
Battery Charging Alternator
Lead-acid storage batteries contain sulfuric acid,
which if handled improperly, may cause serious
burns on the skin or other serious injuries. Wear
protective gloves, aprons, and eye protection
when handling and servicing lead-acid storage
batteries. See the precautions in General Informa-
tion, Section A, of this manual to ensure proper
handling of the batteries and/or accidents involv-
ing sulfuric acid.
Maintenance and Service
Check the electrolyte level of each cell at the interval
specified in Lubrication and Service, Section P. Add
water, if necessary. The proper electrolyte level is 10
to 13 mm (0.375 - 0.50 in.) to above the plates. To
ensure maximum battery life, use only distilled water
or water recommended by the battery manufacturer.
After adding water in freezing temperature, operate
the engine for at least 30 minutes to thoroughly mix
the electrolyte.
DO NOT smoke or allow a flame around a dead
battery or during recharging. The expelled gas
from a dead battery cell or a charging battery is
extremely explosive and can cause serious
bodily injury.
Excessive consumption of water indicates leakage or
overcharging. Normal water usage for a truck operat-
ing eight hours per day is about 30-60 ml (1-2 oz) per
cell, per month. For heavy-duty operation (24 hours
per day), normal consumption is about 30-60 ml (1-2
oz) per cell, per week. Any appreciable increase in
water consumption is considered a danger signal. No
water consumption may indicate undercharging or
sulfated battery plates.
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