PERCENT OF CHARGE
75%
50%
25%
0%
2 AMPS
6.5
12
NR
NR
10 AMPS
1.8
3.0
4.5
6
25 AMPS
0.8
1.4
2
2.7
* Not recommended
The times shown in the chart above are approximate and refer to an average automotive battery. For smaller batteries, the charge
time should be adjusted using the formula shown below and adding 1 hour to the time calculated.
To estimate charging time for a discharged battery, divide the amp hour (aH) rating of the battery by the charge rate selected. This
is the number of hours required to recharge the battery. For example, a 50 AH (12 volt) battery is discharged (10 volts). How long
should it be charged at the 10 Amp rate? Divide the 50 AH by 10.
Answer:
5.5 hours. Always round up the charge time by 10% to ensure full charge. In most cases, battery charging times will vary
depending on the age and condition of the battery. Smaller batteries should be charged at a lower rate (2 Amps) and add an extra
hour to charge time.
CHARGING TIMES
The VEC1095A, a fully automatic Smart Battery Charger will automatically adjust the charge rate as the battery becomes
charged and stops charging when the battery is fully charged. For estimates of the time it takes to charge a battery refer to
the following table for details. Deep cycle batteries may need longer charging time. It is recommended to repeat the charg-
ing cycle a second time beginning with the 2 AMP rate.
The following chart converts hydrometer readings into percent of charge values.
Refer to the chart below for approximate charging times.
SPECIFIC GRAVITY
PERCENT OF CHARGE
PERCENT OF CHARGE NEEDED
(HYDROMETER READING)
IN BATTERY
BY BATTERY
1.265
100%
0%
1.225
75%
25%
1.190
50%
50%
1.155
25%
75%
1.120
0%
100%
Refer to Chart below for approximate Charging Time
WARNING: DO NOT ATTEMPT TO CHARGE A FROZEN BATTERY
VERY COLD BATTERY
If the battery to be charged is extremely cold (in temperatures less than freezing - 0º C/32º F) it cannot accept a high rate of
charge, so the initial charge rate will be slow. The rate of charge will increase as the battery warms.
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