Battery Load Testers

Your vehicle’s battery is not very demanding, and most often only thought about when it fails.  But just a small amount of care and maintenance will help insure it doesn’t let you down when you need it most.  Load testing, using devices commonly referred to as Volt-Amp Testers (VAT), is an easy way to help maintain your battery for years to come.

Battery load testers check your vehicle's charging system under working conditions, and helps takes the guesswork out of electrical diagnosis, making it easy to pinpoint charging system failures.  A load test is used to determine if the battery can deliver both voltage and current at the same time.  Not only do load testers target the battery, but they also test the alternator, regulator, and starter motor. 

The tester consists of a large resistor that has a resistance similar to a car’s starter motor and an easy-to-read meter to read the battery’s output voltage, both in the unloaded and loaded state.  First, the tester checks the open circuit voltage to make sure the battery is charged.  If the open circuit voltage is below spec, the battery is charged.  After reading the battery’s open circuit voltage, the load is applied.  When applied, it draws approximately the same current the car’s starter motor would draw during cranking.  If the voltage under load falls below a certain point, the battery is determined to be bad.  Load tests are also used on running cars to check the output of the car’s alternator.

If the battery passes the load test, you should recharge it as soon as possible to prevent lead sulfation and to restore it to its peak performance. Call Powerstide today with your questions or to order battery load testers.