Battery Tester Large Screen LCD Digital Display Black White Screen Battery Life Universal Tester 12V 24V Battery Tester Item Type: Battery Tester Product Material: ABS 12V: 12V Battery, Generally Used In Gasoline Vehicles 24V: 24V Battery, Generally Used By Diesel Vehicles Electric Vehicle: Generally Used For Testing Electric Vehicles, Single Test Separately (Multiple Battery Pack Tests Are Prohibited) Unknown: When The Battery Standard And Capacity Cannot Be Determined, This Item Can Be Selected (Note: This Item Can Only Measure The Current Power, Not The Life.) CCA Standard: Cold Cranking Current IEC Standard: International Electronic Technology Association EN Standard: European Industrial Standard DIN: German Industrial Standard JIS: Japanese Industrial Standard VRLA GEL AGM SLA: Lead Acid Batteries For Vehicles STANDARD LSI: Start Stop Battery For Vehicles Weight: Approx.413g / 14.6oz 1. The inverter is installed on the car, will it affect the results? All inverters will affect the test results of the meter, so please remove the inverter before measuring to ensure the correctness of the test. 2. Can this product accurately predict when the battery will fail? The internal resistance of sealed lead acid batteries is complex, which includes the ohmic internal resistance of the battery, the internal resistance of the concentration difference polarization, the internal resistance of the electrochemical reaction, and the interference effect of the double layer capacitor charging. The components and their relative contents contained in the internal resistance values measured by different test methods and at different times are different, so the measured internal resistance values are also different. There is no strict mathematical relationship between the internal resistance (or conductance) and battery capacity of sealed lead acid batteries, and the battery life cannot be predicted based on the internal resistance (or conductance) value of a single battery. However, when the internal resistance of the battery suddenly increases or the "CCA" suddenly decreases, it indicates that the battery life is about to end. 3. Is the CCA value measured by this product accurate? CCA is a control standard in battery production. According to the accumulated results, the measured value of the new battery will be higher than the marked value (10 to 15%), and will gradually approach the marked value as the battery is used, and then lower than the marked value. 4. The difference between this product testing method and the load testing method This method has evident shortcomings: (1) Only large capacity batteries or accumulators can be measured, and small capacity batteries cannot load a large current of 40A to 80A within 2 to 3 seconds. (2) When the battery passes a large current, the electrode inside the battery will be polarized, resulting in polarization internal resistance. Therefore, the measurement time must be very short, otherwise the measured internal resistance value has a large error. (3) The large current passing through the battery will damage the electrodes inside the battery to a certain extent. Measurement of this product: Advantages of this method: (1) Almost all batteries, including small capacity batteries, can be measured using this measurement method. (2) Measurement by this method will not cause much damage to the battery itself.