DieHard 200.71240, Operator'S Manual

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The hydrometer or Electronic Method 12.2
To find the time needed to fully charge your battery, determine the bat-
tery’s charge level with a hydrometer or electronic Percent-of-Charge
Tester. The following table will help you convert hydrometer readings to
percent of charge values.
SPECIfIC GRAvITY PERCENT Of ChARGE PERCENT Of ChARGE
NEEdEd
1.265 100% 0%
1.225 75% 25%
1.155 25% 75%
1.120 0% 100%
When you know the percent of charge and the Amp Hour (AH) rating of
your battery, you can calculate the approximate time needed to bring your
battery to a full charge.
To
convert Reserve Capacity to Amp Hours, divide Reserve Capacity by
2, and add 16:
Amp Hours = Reserve Capacity + 16
2
NOTE : The Reserve Capacity can be obtained from the battery specifica-
tion sheet or the owner’s manual.
To calculate time needed for a charge:
Find the percent of • charge needed . (A battery at 50 percent charge that
will be charged to 100 percent needs another 50 percent (.50)).
Multiply the Amp Hour rating by the charge needed (.50) and divide by
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the charger setting (2 or 10 amps).
Multiply the result by 1.25 and you’ll have the approximate time needed,
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in hours, to bring the battery to full charge.
Add one additional hour for a deep-cycle battery.
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Example:
Amp Hour Rating x charge needed x 1.25 = hours of
Charger Setting charge
100 (AH Rating) x .50 (charge needed) x 1.25 = 6.25
50 (Charger Setting) hours
100 x .50 = 1.25 x 1.25 = 1.5625
50
You will need to charge your 100-Ampere Hour Battery for approximately
1 1/2 hours at the 50-Amp charge rate using the above example.