Battery Charging
To minimize possible damage to the battery and allow the battery to be fully charged, the slow charging meth- od is presented here. This charging method can be ac- complished with a constant current battery charger which is readily available locally.
CAUTION
Follow the manufacturer’s instructions when us- ing a battery charger.
NOTE: Using specific gravity of the battery cells is the most accurate method of determining battery condition.
1.Determine the battery charge level from either its specific gravity or open circuit voltage.
Battery Charge | Specific | Open Circuit |
Level | Gravity | Voltage |
|
|
|
100% | 1.265 | 12.68 |
|
|
|
75% | 1.225 | 12.45 |
|
|
|
50% | 1.190 | 12.24 |
|
|
|
25% | 1.155 | 12.06 |
|
|
|
0% | 1.120 | 11.89 |
|
|
|
2.Determine the charging time and rate using the bat- tery charger manufacturer’s instructions or the fol- lowing table.
Battery |
| Battery Charge Level |
| |||
Reserve | (Percent of Fully Charged) | |||||
Capacity |
|
|
|
|
|
|
(Minutes) | 75% |
| 50% | 25% |
| 0% |
|
|
|
|
|
|
|
80 or less | 3.8 hrs |
| 7.5 hrs | 11.3 hrs |
| 15 hrs |
| @ |
| @ | @ |
| @ |
| 3 amps |
| 3 amps | 3 amps |
| 3 amps |
|
|
|
|
|
|
|
81 to 125 | 5.3 hrs |
| 10.5 hrs | 15.8 hrs |
| 21 hrs |
| @ |
| @ | @ |
| @ |
| 4 amps |
| 4 amps | 4 amps |
| 4 amps |
|
|
|
|
|
|
|
126 to | 5.5 hrs |
| 11 hrs | 16.5 hrs |
| 22 hrs |
170 | @ |
| @ | @ |
| @ |
| 5 amps |
| 5 amps | 5 amps |
| 5 amps |
|
|
|
|
|
|
|
171 to | 5.8 hrs |
| 11.5 hrs | 17.3 hrs |
| 23 hrs |
250 | @ |
| @ | @ |
| @ |
| 6 amps |
| 6 amps | 6 amps |
| 6 amps |
|
|
|
|
|
|
|
above | 6 hrs |
| 12 hrs | 18 hrs |
| 24 hrs |
250 | @ |
| @ | @ |
| @ |
| 10 amps |
| 10 amps | 10 amps |
| 10 amps |
|
|
|
|
|
|
|
CAUTION
Do not charge a frozen battery because it can ex- plode and cause injury. Let the battery warm to 60oF (15.5o C) before connecting to a charger.
Charge the battery in a
3.Following the battery charger manufacturer’s instructions, connect the charger cables to the battery. Make sure a good connection is made.
4.Charge the battery following the battery charger manufacturer’s instructions.
5.Occasionally check the temperature of the battery electrolyte. If the temperature exceeds 125oF (51.6oC) or the electrolyte is violently gassing or spewing, the charging rate must be lowered or temporarily stopped.
6.Three hours prior to the end of the charging, mea- sure the specific gravity of a battery cell once per hour. The battery is fully charged when the cells are gassing freely at a low charging rate and there is less than a 0.003 change in specific gravity for three consecutive readings.
Electrical System | Page 5 | Groundsmaster |
