Battery: Testing and Inspection
Visual inspection
Before measurements such as open-circuit voltage, specific gravity of electrolyte or the battery load test are carried out. a visual inspection of the battery must be performed.
Through this check, it can be determined:
^ Whether the housing of the battery is damaged. Acid can leak out due to damage of the housing.
^ Whether the battery terminal (battery line connections) are damaged. Contact of the line connections cannot be guaranteed if the battery terminal is damaged. This can cause a line fire and malfunctions in the electrical system.
Check acid level
Caution!
The accident prevention regulations must be observed when handling battery acids.
Wear suitable protective clothing and protective glasses.
Only illuminate the inside of the battery with a flashlight.
Never illuminate the inside of the battery with a naked flame.
Do not handle a naked flame or burning cigarettes near to batteries.
Observe the disposal regulations for batteries and when disposing of batteries and sulfuric acids.
Note!
^ Use commercially available battery filling bottle.
^ The correct acid level of the battery is an important factor for long and efficient operation of the battery.
^ When the acid level is too low, a capacity loss (performance loss) of the battery occurs which is caused by the cell plates drying out. If the cell plates are not surrounded by electrolyte (battery acid), it will lead to corrosion of the lead plates, the plate bridges and the cell connectors. The result of the corrosion is that the function of the battery cannot be guaranteed. The battery will become useless.
^ If the acid level is too high, damage can occur by the battery acid leaking out (sulfuric acid water mixture) outside the battery.
1. Switch ignition off and remove ignition key.
2. Remove battery cover.
3. Unscrew plugs of the battery.
4. Illuminate into the battery using a flashlight. The electrolyte level of the battery must be at the protruding "lug".
- If the acid level is too low, refill distilled water using the battery filling bottle.
5. Screw in plug of the battery again ensure that it is seated correctly.
6. Remount battery cover.
Checking specific gravity of electrolyte
Caution!
The accident prevention regulations must be observed when handling battery acids.
Wear suitable protective clothing.
Observe the disposal regulations for batteries when disposing of batteries and sulfuric acids.
Note!
^ Use commercially available battery acid tester.
^ The specific gravity of electrolyte test provides information about the state of the battery in connection with the battery load test
^ The temperature of the battery acid must be at least 10°C.
The specific gravity of electrolyte must be checked in all battery cells as follows:
1. Switch ignition off and remove ignition key.
2. Unscrew all battery plugs (plugs of the battery cell).
3. Dip into the battery cell using the acid siphon or the pipette and take up the battery acid.
4. Read off the specific gravity of electrolyte in kg/dm3 on the scale of the battery acid tester and compare with the table shown.
The specific gravity of electrolyte must be at least 1.24 kg/dm3.
- If the specific gravity of electrolyte is too low, charge battery.
- After charging the battery, repeat the specific gravity of electrolyte test.
The measuring values for the specific gravity of electrolyte of the individual battery cells should not deviate by more than 0.03 kg/dm3 from each other.
Example 1: The specific gravity of electrolyte in cell 4 is too low.
Example 2: The specific gravity of electrolyte in cells 4 and 5 is too low. The specific gravity of electrolyte deviations between the battery cells is larger than 0.03 kg/dm3.
- If the nominal values are not achieved, replace battery.
- If the nominal values are achieved, screw in the original plug again.
Open-circuit voltage measurement
Note! Use a hand-held multimeter to measure the battery voltage.
1. Switch ignition off and remove ignition key.
2. Disconnect ground strap on the battery.
Note! After charging and a waiting time of at least 2 hours during which the battery should neither be burdened or charged.
3. Measure the battery voltage with a hand-held multimeter.
- The battery open-circuit voltage should not fall below 12.5V.
- If the hand-held multimeter shows 12.5V or over, the battery voltage is OK.
- If the hand-held multimeter shows a battery voltage below 12.5V: Charge battery.
Battery load test
Note!
^ The gravity of electrolyte test provides information about the state of the battery in connection with the battery load test.
^ A battery test device is required for the load test.
^ The battery must not be removed or disconnected
^ The battery must be charged before the load test is performed.
Carry out battery load test:
1. Switch ignition off and remove ignition key.
2. Observe the information in the operating instructions of the battery test device.
3. Connect the pliers of the test lines to the battery terminal as described in the operating instructions of the test device.
- As the load current varies, the current must be set depending on the battery capacity (operating instructions of test device).
The load test currents can also be referred to in the tables shown.
4. Carry out the battery load test according to the operating instructions and compare to the test result of the tables shown.
- A minimum voltage is determined by the battery load test depending on the specified battery voltage.
5. If the minimum voltage is not attained, replace battery.
Remarks on battery load test:
^ The battery voltage sinks during this test due to the severe load on the battery.
^ If the battery is in order, the voltage value only reduces to the minimum voltage.
^ If the battery is faulty, the battery voltage will sink very quickly below the specified minimum voltage.
^ After the test has taken place, the low voltage value remains over a long period of time, the voltage increases again slowly.