DRESSTA TD-25M EXTRA, Service Manual

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ELECTRICAL
SECTION 8
Page 35
DRESSTA TD-25M EXTRA
BATTERY
b. The State of Charge Batteries at Various Climate
The state OFF charge batteries at various climate shows chart below.
State
of charge
Specific gravity
in arctic climate
Specific gravity
in tropical climate
100 [%] 1.265 1.225
75 [%] 1.225 1.185
50 [%] 1.190 1.150
25 [%] 1.155 1.115
Discharged 1.120 1.080
c. Arctic Climate
Batteries used in arctic climate use stronger electrolyte of 1.290 to 1.300. Higher specific gravity
decrease the service life of the battery.
As the battery approaches the discharged condition, the easier it is for its electrolyte to freeze.
d. Electrolyte Freezing Point
Electrolyte freezing point shows chart below.
Freezing point Specific gravity
-10 [
°
C] 1.120
-27 [
°
C] 1.200
-54 [
°
C] 1.255
-65 [
°
C] 1.270
13. TESTING AND MAINTENANCE THE BATTERY
a. Visual Inspection
Visually inspect the outside of the battery for obvious damage such as a cracked or broken case
or cover which would allow electrolyte loss. If top of a battery is dirty, secure vent plugs, clean it
with a brush dipped in ammonia or soda solution. After foaming stops, flush of battery with clean
water. Check for terminal damage. Brighten terminal contact surfaces with steel wool or a stiff
brush. Check the condition of the battery cables.
b. Electrolyte Levels and State of Charge
In abnormal conditions (above 32 [
°
C] and below 0 [
°
C]) it is recommended to check electrolyte
level frequently, to prevent electrolyte within cells from evaporating below top of plates. Although
these batteries are designed to preclude the need to add water, the volume of reserve electrolyte
above the plates may eventually be depleted. In most cases, this will signal the end of the battery
´
s
useful life. If electrolyte levels are found to be low or a battery is in a deep state of discharge,
check for charging system malfunction and/or loose battery trays and hold-down clamps. Add
water before proceeding further. The state-of-charge of low water loss batteries can be determined
with an accurate voltmeter.