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 sulphuric acids.
NOTE:
- Use commercially a variable 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.
- Switch ignition off and remove ignition key.
- Unscrew all battery plugs (plugs of the battery cell).
- Dip into the battery cell using the acid siphon or the pipette and take up the battery acid.
- Read off the specific gravity of electrolyte in kg/dm3 on the scale of the battery acid tester and compare with BATTERY SPECIFICATIONS (NORMAL CLIMATIC ZONE) .
BATTERY SPECIFICATIONS (NORMAL CLIMATIC ZONE)
| Battery charging condition in normal climatic zones | Spec, gravity in kg/dm 3 |
|---|---|
| discharge | 1.12 |
| half charged | 1.20 |
| well charged | 1.28 |
BATTERY SPECIFICATIONS (TROPICAL CLIMATIC ZONE)
| Battery charging condition in tropical climatic zone (hot countries) | Spec, gravity in kg/dm 3 |
|---|---|
| discharge | 1.08 |
| half charged | 1.16 |
| well charged | 1.23 |
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.
NON-PERMISSIBLE BATTERY ELECTROLYTE SPECIFIC GRAVITY DEVIATIONS
| Examples of non-permissible specific gravity of electrolyte deviations: | ||||||
|---|---|---|---|---|---|---|
| Battery cells: | 1 | 2 | 3 | 4 | 5 | 6 |
| Specific gravity of electrolyte per cell in kg/dm3 | ||||||
| Example 1: | 1.24 | 1.25 | 1.25 | 1.10 | 1.24 | 1.25 |
| Example 2: | 1.26 | 1.26 | 1.25 | 1.14 | 1.18 | 1.24 |
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.