Vector VEC090 Owner's Manual & Warranty Information page 11

APPENDIX A APPENDIX A CHARGING TIMES CHARGING TIMES
—
To calculate the approximate charging time required to fully charge a battery,
determine the specific gravity (or, percent of battery charge) using a hydrometer. Use this technique if
battery vent caps can be removed. Check each cell. if there is one cell with a very low specific gravity
compared to the other cells, there is probably a shorted cell in the battery. Replace the battery.
The following chart converts hydrometer readings into percent of charge values.
SPECIFIC GRAVITY SPECIFIC GRAVITY
(HYDROMETER READING) (HYDROMETER READING)
1.265
1.225
1.190
1.155
1.120
Refer to the chart below for approximate charging times.
PERCENT OF CHARGE PERCENT OF CHARGE
2 AMPS
10 AMPS
2OAMPS
* For Charging Batteries 80 to 100 AH (not for this example)
** Not Recommended for more than 1 hour
*** Not Recommended because over 18 hrs charging time.
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 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
20. The answer is approximately 2.5 hours. Always round up the charge time by 10% to ensure full
charge. In most cases, battery recharge 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.
PERCENT OF CHARGE PERCENT OF CHARGE NEEDED PERCENT OF CHARGE PERCENT OF CHARGE NEEDED
IN BATTERY IN BATTERY
100%
75%
50%
25%
0%
75% 75% 50% 50%
6.5 HRS 12 HRS
1 .8 HRS 3.0 HRS
1 HRS 1.5 HRS
BY BATTERY BY BATTERY
0% 0%
25%
50%
75%
100%
25% 25% 0% 0%
N.R*** N.R***
4.5 HRS 6 HRS
3HRS 3.5HRS
be charged at the 20 Amp rate. Divide the 50 AH by
it
11 11
is necessary to
it
VECO9O