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Voltage, Checking Under Load




Voltage, Checking Under Load

Special Tools and Equipment







- VAS 5096 (was VAS 1979)
or
- VAS 5097 (was VAS 5033)


NOTE: If you are using VAS 1979 or VAS 5033 battery tester to test the battery, you do not need to remove the battery. You also do not have to disconnect the battery.


WARNING!
Observe safety precautions, wear protective clothing such as a protective visor and leather gloves.



Test sequence
- Switch ignition off.
- Read battery tester operating instructions.
- Connect the clips to the battery terminals according to the instructions for the tester. The dips must make good contact with the battery terminals.
- The load current varies depending on the battery capacity, and has to be adjusted on the tester.







The load test currents can also be taken from the table.
- Perform battery load test according to operating instructions and compare test result with table.
The load test determines the minimum voltage indicated according to battery capacity.
The load current and the minimum voltage vary depending on the battery capacity.

- If the minimum voltage is not reached, replace the battery.

Explanation for battery load test:
The strong load (resistance) during this test (a high current is flowing) reduces the battery voltage.
If the battery is in good condition, the voltage drops only to the minimum voltage.
If the battery is malfunctioning or only faintly charged, the battery voltage will drop rapidly to below the displayed minimum voltage.
After the test has been performed, the voltage will remain at this low value for a long time, and will climb back up only very slowly.