Digital battery tester, includes alternator and starter motor tests.
What does the tester do?
Simply measuring battery voltage is not a true indication of the state of a battery. A battery test has 2 aspects to it: There is the voltage of the battery (which is a rough indication if the battery is fully charged). Then, there is the ability of the battery to hold and deliver the power it has stored. I.e the voltage could show the battery is fully charged but the battery could be badly sulphated and useless. You need to test the voltage of the battery under a heavy load condition.
The load test:
- Depending on the size of the battery, this product adds a very high load to the battery (125 A). The battery should be able to deliver this load and hold the voltage up at the same time. If the battery is unable to deliver the load (and sustain it for this time frame) then the battery is either defective or simply not fully charged when the test was performed. This is why it is crucial to ensure the batteries are fully charged before the test is performed to eliminate that possibility.
To test simply connect the unit to a 12V fully charger battery, adjust the CCA (cold cranking amps) on the screen up to 999A, then press the load button and perform the 10 second test. The unit will inform you if the battery is good, weak or bad.
The unit can also be used to measure the performance of the charging device (alternator / battery charger) – to inform the user whether the charging device is good, weak or bad.