DieHard 28.71234 - Page 17

• 15 •
BATTERY SIZE/RATING
CHARGE RATE/
CHARGING TIME - HOURS
2 AMP 20 AMP 60 AMP
SMALL
BATTERIES
Motorcycle, gar-
den, tractor, etc.
6 - 12 AH 2 - 4 NR NR
12 - 32 AH 4 - 10 NR NR
CAR/TRUCKS
200 - 315 CCA 40 - 60 RC 11 - 14
60 - 90
min.
20 - 30
min.
315 - 550 CCA 60 - 85 RC 14 - 18
90 - 120
min.
30 - 40
min.
550 - 1000 CCA 85 - 190 RC 18 - 35
2 - 3.5
hrs.
45 - 60
min.
MARINE/DEEP CYCLE
80 RC 18 105 min. NR
140 RC 27
2 hrs.,
45 min.
NR
160 RC 30 3 hrs. NR
180 RC 33 3.5 hrs. NR
The Hydrometer or Electronic Method14.2
To nd 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 specica-
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