Diesel Engine Battery Voltage and Current Testing

The voltage and current testing methods for diesel engine batteries include load testing, 3-minute charging testing, battery external circuit leakage testing, resistance range testing with a multimeter, and so on. Below, Dingbo Company will provide a detailed explanation for everyone.

1. Load testing. The best testing method for the performance of lead-acid batteries is load testing. To ensure correct results during testing, it is required that the battery level be at least 75% or higher. If the electrolyte density is less than 1.22g/cm3 and the starting voltage does not reach 1.24V, it should be fully charged before testing.

High rate discharge meters can be used to perform load testing on batteries. There are two types of 12V integrated battery high rate discharge meters: variable current type and constant current type. Currently, the constant current type is widely used in China. During the test, forcefully insert the discharge meter into the positive and negative electrodes and hold for 15 seconds. If the battery can maintain above 9.6V, it indicates good performance, but insufficient power; If it can stabilize at 10.6~11.6V, it indicates that the battery is fully charged; If the voltage drops rapidly, it indicates that the battery is damaged.

Using a variable load high rate discharge meter, three times the Qe value can be used as the test current. For 12V integrated batteries, using 180A as the rated load current value can achieve satisfactory results in most cases.

If there is no high rate discharge meter, under normal starting system conditions, the starter can be used as the test load. The steps are as follows: 1. Remove the central wire of the distributor and ground it; 2. Connect the digital voltmeter to the positive and negative terminals of the battery; 3. Turn on the starter for 15 seconds and read the voltmeter reading. For a 12V battery, the voltmeter reading should not be lower than 9.6V.

2. 3-minute charging test. This test is used to determine whether a discharged battery can continue to be used. Remove the battery and charge the 12V battery continuously for 3 minutes with a current not exceeding 40A. When charging for 3 minutes, if the charging voltage exceeds 15.5V, it indicates that the battery is faulty and should be replaced; If it does not exceed 15.5V, additional charging can be carried out according to the manufacturer's recommended value.

3. Battery external circuit leakage test. Leakage testing is used to determine whether there are still certain electrical components or components consuming battery energy when all circuits are cut off. There are several methods available:

1) "Scraping" method: Cut off all switches, close the car door, remove the battery grounding wire, and "scrape" the negative terminal of the battery. If there is a spark, it indicates that the circuit is leaking.

2) Lamp test method: After removing the grounding wire, connect a low-power test lamp in series between the negative terminal of the battery and the grounding wire. If the test lamp lights up, it indicates a leakage in the circuit.

3) Voltmeter or ammeter test: Some electronic components in automobiles or construction machinery continue to consume power even when all switches are turned off, but their values are very small. These components include digital clocks, electronic tuning (radio memory) transceivers, and diodes for engine control microcomputers. To check the power consumption of these electronic components when the ignition switch is turned off, a voltmeter or ammeter can be used for testing.

Dingbo Power was founded in 1974 and is one of the earliest manufacturers of generators and diesel generator sets in China. If you want get more information, please feel free to send email to sales@dieselgeneratortech.com we will pay highly attention on your question.