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Using a Car Battery Tester

Omkar Phatak
If you are looking for information about the use of a battery tester, this Story will be a helpful read.
Your car's battery is its power house, which enables all the electrical and electronic accessories to function smoothly. With a dysfunctional battery, you cannot hope to even get the ignition working. Ergo, it's essential that the car battery testing be carried out periodically. You can check it using a tester or a simple multimeter. These are specially built electronic devices, for testing battery voltage levels. They make it easier for you to regularly monitor battery health.


Testing a battery is monitoring its voltage levels. There are three important levels to consider. The first type of level to be tested is the no-load voltage level, with the engine switched off. This one needs to be around 12 V, with the engine switched off.
The second is cranking voltage level, which will drop below 12 V, as the engine starts. The third voltage reading, that needs to be checked, is the charging level, when the alternator is functional and the battery is getting charged, with the engine running. This one needs to be around 13.8 to 14 V.
If during testing, any of these three levels are substantially below their normal value, you are facing either battery or alternator problems. Regular use of a tester can point out alternator and battery problems. The essential point to be noted is that a battery shows different voltage levels, at different applied loads.
Hence, it's essential that a tester applies different loads to correctly assess the battery health. The applied load should be proportional to the maximum load rating of the car battery. Make sure that the battery has cooled down, when you test it, as temperature variation can affect readings.


Let us now look at the features and kinds of available testers. There are primarily two types, which include analog and digital ones. Some are small enough to be plugged into cigarette holders and some need to be attached to the terminals.
Most advanced testers use the BCI test, which involves the application of half the load rating of the battery, to test its health. This test simulates the load that will be applied by your car accessories on the battery, by application of the load for about ten to fifteen seconds. To use the tester, you must attach it to the battery terminal and monitor the reading. These devices derive power from the battery itself. Standalone battery load testers have a capacity of absorbing as much as 100 amperes or more of current. Service centers have a tester, with a printer, to get a numerical readout.
An ideal tester must be able to check no load, cranking, as well as charging voltage levels. Check out reviews in detail before choosing one. It doesn't matter much, whether it's analog or digital, as long as it provides accurate readings within 0.1 V error margin. Some of the leading manufacturing brands of battery testers are Associated Equipment and Midtronics. You can buy a decent one for less than USD 50.
Buying one is a useful investment as they form important tools in your car's maintenance arsenal. You can ensure good battery health, with a handy tester by your side.